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1. Assume SS Equals DS N y ef ines HN 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 13 g J Project TEST Step 3 Set Code generation options Code Generation 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 15 Step 4 Set Advanced code generation options roject pplication options Advanced C options ptimizations me ource essages ames elp Instruction set oO Far Data hreshold EEIZ Step 5 Set Debugger options indow elp pplication ompiler ransfer ake inker nvironmeni Inspectors 52 PRE RARE Ce None O d Display Swappin x rogram Heap Size MEME K bytes Page 16 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 Step 6 Make the project 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 17 4 BSD Socket Interface 4 1 About BSD Sockets The BSD 4 3 sockets are the closest thing there is to a standard user interface to TCP IP However they can only be approximated on a non UNIX system because many UNIX functions interact with sockets Writing New Code For somebody who already knows the BSD sockets writing any new code using them makes sense The Dynamic Protocol Interface Refer to Chapter 5 needs quite a bit less space but the difference in speed is no
2. The sendmsg function is a send function that allows the data to be sent to be split into an array of buffers Here is the definition of the msghdr structure struct msghar Message header for recvmsg char msg_name optional address int msg_namelen size of address struct iovec msg_iov scatter gather arra int msg_iovlen num of elems in msg_iov char msg_accrights access rights int msg_accrightslen struct iovec address and length char iov_base base intiov_len size Reference send sendto Return Value 1 Error gt 0 Number of bytes sent 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 45 4 1 20 sendto e Description Send a message e Syntax int sendto int s char buf int len int flags struct sockaddr to int tolen e Input Parameter s Socket identifier buf Buffer from which information will be sent len Number of bytes to send flags Specifies optional behavior MSG_OOB sends the data as urgent data MSG_DONTROUTE ensures that the message is not sent through a default router to Specifies the remote host to which the connection should be made tolen Size of the to data structure The sendto function allows a connection to be made and a message to be written to the connection Reference send sendmsg e Return Value 1 Error gt 0 Number of bytes sent e Example rc sendto s HIJKLMNO 8 0 struct so
3. address family char sa _data 14 up to 14 bytes of address In practice this is used almost as a void pointer The true Internet address structure is struct in_adar Internet address unsigned long S_adar struct sockaddr_in Internet socket address short sin_family unsigned short sin_port struct in_addr sin_adar char sin_zero 8 J Please refer to tcpip h for more details ICPDAS CD Napdos MiniOS7 tcpip_lib BSD Socket Interface Functions The BSD Socket Interface provides these function calls accept accepts a connection on a socket bind binds a name to a socket closesocket closes a socket connect initiates a connection on a socket fentlsocket controls socket flags gethostbyname returns the IP address that corresponds to a host name getpeername extracts the remote address information for a socket getsockname extracts the local address information for a socket getsockopt gets options on sockets ioctisocket sets control parameters for a socket listen listens for connections readsocket receives a message from a socket ID recv receives a message recvfrom receives a message from a connection recvmsg establishes a connection and receives a message selectsocket waits for activity on a set of sockets send sends a message on an established connection 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 19 send
4. 0 Normal close EBADF The connection number is invalid No closing was performed ECONNABORTED Protocol problem If you have been writing data to the other system consider the dataunsafe Connection is closed e Example int error error code int conno connection number error Nclose conno close the connection if error lt 0 process error 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 61 5 5 3 Nread e Description Reads a message from a connection e Syntax int Nread int conno char buff int len e Input Parameter conno Connection number buff Buffer to store message len Size of the buffer Reads a message from a connection into the specified buffer For a blocking socket the call will block until information is available to be read or until a timeout occurs The timeout can be adjusted using the SOCKET_RXTOUT macro For TCP connections Nread may return up to the maximum amount of information that will fit in one internal message buffer This will be less than MAXBUF bytes For UDP connections the data from the next UDP message will be returned e Reference Nclose Nopen Nwrite e Return Value 0 The remote system has closed the connection count Values gt 0 indicate the number of bytes read EBADF The connection number is not valid EWOULDBLOCK Non blocking connection can t proceed Read would be retried ETIMEDOUT Timeout Read can be retried E
5. 4 1 21 SAUNA E 47 4 1 22 SOCKET AA A AA wh ee GR des M ahaa 48 4 1 23 Wwritesoeketb nira A dada da 49 5 DYNAMIC PROTOCOL INTERFACE semeemenenenenenennnensenensesensesesseneneses 50 3 1 OVERVIEW ernn eaea da dt tri tty 50 32 BLOCKING VERSUS NON BLOCKING OPERATION users 50 5 3 INITIALIZATION AND TERMINATION cccssccescceesseceereecsaeceeneecsaeceneecsaeceneeesaeceeneecsaeceeeeecaeeeeeeessaeeees 50 SIN INNER ot AR E E eas At Tr A aaah a Oe Nee es ac Ann a as ne 51 DDD INTEP Minis ES RN 92 DI A 210 1 11 TR TE a eo dee da nu 53 E IN A rte E atsbren enut es elueb ess 55 5 4 CONNECTION Sri did ais 56 5 5 OPEN CLOSE READ AND WRITE scsssssccceceesessscececececsesscaecececeesesaaeceeccecseuaaeceeeceesesssaeceeeeeeeensaaeees 57 2 3 1 9719 CA OS O OO ae 38 MZ NolOSezsisssinnesinst finite elite ideal tes 6l A MN o 62 S4 NWE ese RN 64 5 6 DYNAMIC PROTOCOL INTERFACE MACROS eee 66 5 61 SOCKET NOBEOCK ii deis debian 67 36 25 SOCKET BLOCK ot rats A de a oo aa hess 67 5 6 3 SOCKET ISOPEN cado tt dt tt aida state 67 56 4 SOCKET SI Y AAA 68 5 6 5 SOCKET CANSEND oia iii 68 5 06 SOCKET TES N 0 a 68 9 67 gt SOCKETS MAXDAT less ace A OAL AR o a 68 5 6 8 SOCKET _RXTOUT AAA 69 56 9 SOCKET IPADDR AAA EN Na E EATR AE AE EIE E OAE N ES 69 5 6 10 SOCKET OWNIPADDR 00 IA a ea SEE RR aan 69 5 6 11 SOCKET PUSH brii a e A A a ods da 69 5 6 12 SOGCKELE EIN ESEAS A E A 70 Broadcasting Example viii iia eiii 70 Non Blocking Operation
6. 0 Page 9 1 7 Connectionless Protocol Client Server Client side data sent blocks until data is receiced from client Figure 4 Connectionless Protocol UDP Server side reply Page 10 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 2 Software Installation o For the 7188E 843X 883X 844X 884X series The software for the 7188E 843X 883X 844X 884X consists of one CD ROM Directories of CD ROM Napdos MiniOS7 tcpip_lib For example D 8000 Napdos MiniOS 7 tcpip lib gt xcopy e s c tcpip 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 11 3 Compiling amp linking User must use C Language when writing programs You can use TC BC MSC or MSVC before 1 52 Please take care of the following items gt Generate a standard DOS executable program gt Select CPU 80188 80186 gt Select EMULATION if floating point computation is required can not select 8087 3 1 Using TC O Select standard code Options gt Application e Select EMULATION 80186 Debug info in OBJs cancel Option gt Compiler gt Advanced Code Generation gt m Options Instruction Set SEL Far Data hreshold RYAN eo JS Page 12 e Select None Source Debugging Option gt Debugger gt a Py shew Di gt oy i e Select large mode Options gt Compiler gt Code generation gt
7. 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 55 5 4 Connections Connections behave very much like files You can open and close a connection you can read data from it and write data to it The main difference is that a connection has a user at each end and a file has only one user The data you read is the data the other user wrote and vice versa The library offers the user two basic kinds of connections TCP and UDP There are two primary differences e TCP performs error correction and flow control and UDP does not You can read TCP like a local disk file You want to check for errors but they should not occur and if they do you quit Doing this with UDP would be difficult and writing applications using UDP is quite cumbersome It is best to leave UDP for prewritten applications such as TFTP and BOOTP UDP is a packet protocol and TCP is a byte stream protocol With TCP you can t predict with certainty how many bytes a read will return or how many reads you ll need for a given amount of data Port numbers are used to match the two ends of the connection If your local port number is my remote port and vice versa then we have a connection Normally one end performs an active open and the other a passive open The system performing a passive open is typically running a server application This system will wait until it receives an indication from a client application performing an active open Connecti
8. Note that this should not occur in the current implementation O Timeout occurred gt 0 This number of sockets are ready for the requested operations e Example int s1 S2 s3 sockets int rc return code fd_set socket _set1 socket_set2 FD_ZERO 8socket_set1 FD_ZERO 8socket_set2 FD_SET s1 amp socket_set1 FD_SET s3 amp socket_set1 FD_SET s2 amp socket_set2 rc selectsocket 3 socket_set1 socket_set2 0 NULL if rc lt 0 Print Error no sockets ready n else Print d sockets ready n rc if FD_ISSET s1 amp socket_set1 Print Socket 1 is ready to be read n else if FD_ISSET s2 amp socket_set2 Print Socket 2 is ready to be written n else if FD_ISSET s3 amp socket_set3 Print Socket 3 is ready to be read n else Print Error n Page 42 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 18 send e Description Sends a message on an established connection e Syntax int send int s char buf int len int flags e Input Parameter s Socket identifier buf Pointer to data to be sent len Number of bytes to send flags Allows for these options MSG_OOB sends the data as urgent data MSG _DONTROUTE ensures that the message is not sent through a default router The send function can be used with sockets for which the connection has previously been established eo Reference sendto sendmsg e Return Value 1
9. flags e Input Parameter S Socket identifier msg Pointer to structure that describes how received data should be stored This structure is shown below flags Specifies optional behavior MSG_OOB returns urgent data MSG_PEEK returns information allowing it to be read again on a subsequent call The recvmsg function is the most general of the recv functions This function allows a connection to be established and read with one call The flag MSG_WAITALL is not supported Here is the definition of the msghdr structure struct msghar Message header for recvmsg char msg_name optional address int msg_namelen size of address struct iovec msg_iov scatter gather arra int msg_iovlen num of elems in msg_iov char msg_accrights access rights int msg_accrightslen struct iovec address and length char iov_ base base int iov_len size o Reference recv recvfrom e Return Value 1 Error gt 0 Number of bytes received Page 40 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 17 selectsocket e Description Waits for activity on a set of sockets e Syntax int selectsocket int nfds fd_ set readfds fd set writefds fd_set exceptfds struct timeval timeout e Input Parameter nfds Number of sockets Watch out for off by one errors For example if the highest value of the descriptors that should be evaluated is n nfds should b
10. function but it has been renamed to avoid conflicts with the close function that operates on file descriptors o Reference socket e Return Value 1 Error O Close was successful 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 23 4 1 4 Connect e Description Initiates a connection on a socket e Syntax int connect int s struct sockaddr name int namelen e Input Parameter S Socket identifier Name Structure that identifies the remote end of the connection Namelen Size of name The connect function performs an active open allowing a client application to establish a connection with a remote server The name structure is used to specify the Internet address and port number for the remote end of the connection The Internet address is usually retrieved using the gethostbyname_r function Reference closesocket e Return Value 1 Error O Success connection has been established with the remote server e Example int rc return code struct sockaddr_in socka internet address and port number struct hostent hostent for retrieving IP address from host unsigned char buff BUFFLEN 1 memset amp socka 0 sizeof socka socka sin family AF_INET gethostbyname_r host1 amp hostent buff sizeof buff amp rc if rc lt 0 Print Error gethostbyname_rin memcpy char amp socka sin_adadr char hostent h_addr_list O lid_SZ so
11. or timeout An example of this would be a wait for a return from a TCP open Blocking mode would halt processing until the open returned a connection number or timed out This behavior is usually unsatisfactory for most embedded systems Non blocking allows processing to continue while polling the status of the network event Non blocking is desirable in a non multitasking system because it makes efficient use of CPU time while waiting for network events to complete Non blocking issues are addressed in the appropriate sections in this chapter An example of non blocking is also given at the end of this chapter 5 3 Initialization and Termination Ninit performs general initialization such as initialization of tables and buffers It must be the first network function called and can t be called again unless the function Nterm has been called first Portinit and Portterm are used to initialize and shut down the system s network interfaces Detailed descriptions of these functions follow Page 50 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 5 3 1 Ninit Description Performs general network initialization Syntax int Ninit void Ninit takes no parameters Reference Nterm Portinit Portterm Return Value 0 Success ENOBUFS No buffers configured Check tcpip h variables NCONFIGS and NNETS USER User defined error return from LOCALSETUP found in tcpip h Example main initialize all conne
12. 7188E 843X 844X 883X 884X Networking Library User s Manual Warranty All products manufactured by ICP DAS are warranted against defective materials for a period of one year from the date of delivery to the original purchaser Warning ICP DAS assume no liability for damages consequent to the use of this product ICP DAS reserves the right to change this manual at any time without notice The information furnished by ICP DAS is believed to be accurate and reliable However no responsibility is assumed by ICP DAS for its use nor for any infringements of patents or other rights of third parties resulting from its use Copyright Copyright 2004 by ICP DAS All rights are reserved Trademark The names used for identification only may be registered trademarks of their respective companies 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 1 Table of Contents 1 INTRODUCTION EE E saine ATA der ne esse tencen rame ne A land n e ati ee one n lets tone 4 1 1 PACKAGELIST amp RELEASE NOTES is cccvschcovecscpsceesentevevesosnentsstsnseveseesoteavesnievespeosueseb Ei Ep iann EEn i 4 1 2 WHY ETHERNET SOLUTIONS misa debo 5 1 3 THE 7188EX 7188EA amp 7188EN SERIES 6 1 4 TOPAPATAYER MODEL nement dernier net adrian nn eee aan cacao 8 1 5 INTERNET ADDRESS ssicssstesecssoeveotsdatess cckvercospu sey snestuansusesnievh ire qe ent tr te een recia siria 8 1 6 CONNECTION ORIENTED PROTOCOL o seniste sei anere oe a Tie
13. CONNABORTED Protocol problem Normally the application should close the connection EMSGSIZE The message is too long for the supplied buffer Example user defined input buffer size define MAX_BUFFER_SIZE 80 Page 62 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 int error error code int conno connection Number char buff MAX_BUFFER_SIZE data input buffer read data into buff from connection number conno error Nread conno buff sizeof buff if error lt 0 process error The constant MAX_BUFFER_SIZE could be replaced with the constant MAXBUF defined in file tcpip h A call to Nread cannot return more than MAXBUF bytes 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 63 5 5 4 Nwrite e Description Writes a message to a connection e Syntax int Nwrite int conno char buff int len e Input Parameter conno Connection number buff Buffer containing message len Number of bytes to write Nwrite writes a message to a connection from the specified buffer The largest buffer passed to Nwrite should not exceed the value given by the SOCKET_MAXDAT macro For TCP connections this will reflect the maximum segment size that is indicated by the remote TCP when the connection is established For UDP connections this value will reflect the MTU imposed by the link layer These values will generally be at least 256 bytes so
14. Error gt 0 Number of bytes sent If send returns indicating an error the following error codes could be returned in errno or through getsockopt EBADF The socket descriptor is invalid or another process is using the socket at the moment ESHUTDOWN The application has already requested that the sending side of the socket be shut down No further data can be sent through this socket ECONNABORTED An error has occurred on this socket The socket should be closed EMSGSIZE A non stream socket has been asked to send more information than can be written at once through the socket ENOBUFS The system is out of buffers for sending data The call to send can be retried later 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 43 e Example int s2 socket identifier int rc return code unsigned char buff BUFFLEN rc send s2 buff sizeof buff 0 if rc lt 0 Print Error sending data n Page 44 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 19 sendmsg Description Sends a message that can be split between buffers Syntax int sendmsg int s msghdr msg int flags Input Parameter S Socket identifier msg Pointer to structure that describes the data to be sent This structure is shown below flags Specifies optional behavior MSG_OOB sends the data as urgent data MSG_DONTROUTE ensures that the message is not sent through a default router
15. IP 1000 1010 0 The port com1 is a hosti port not a hostA port This form of open may be needed if there are two connections between host1 and hostA In this manner com1 serves to identify which connection is being opened Note com1 References field 2 in the network configuration table in tcpip lib To send and receive ICMP messages you can use the form 7 host1 conno Nopen host2 ICMP IP 1000 1010 0 Connections This is a special situation see for instance PING C for the use of ICMP Perform a non blocking OPEN and do some processing while polling for the OPEN connection conno Nopen TCP IP 1000 0 S NOWA if conno lt 0 handle error condition while SOCKET_ISOPEN conno perform other processing Page 60 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 5 5 2 Nclose e Description Closes a connection e Syntax int Nclose int conno e Input Parameter conno The connection number previously returned from a call to Nopen Nclose closes a connection possibly waiting for a complete close handshake In no case should the application retry the close In some cases as with TCP the connection block will actually be freed after a minute or so but this is automatic and the application should not touch the connection after the close eo Reference Nopen Nread Nwrite e Return Value
16. OBLOCK conno e Input Parameter conno The connection for which non blocking operation should be set When non blocking operation is set calls to network functions that normally would need to wait for network activity in order to be completed will return the negative value EWOULDBLOCK when such a condition is encountered 5 6 2 SOCKET BLOCK e Description Sets the connection for blocking operation e Syntax SOCKET BLOCK conno e Input Parameter conno The connection for which blocking operation should be set When blocking operation is set calls to network functions run to completion or return a timeout error if an associated time limit is exceeded Blocking operation is the default behavior for network functions and this call will only be needed to return a non blocking connection to blocking operation 5 6 3 SOCKET ISOPEN e Description Checks to see if a connection has entered the ESTABLISHED state e Syntax SOCKET_ISOPEN conno e Input Parameter conno The connection that should be checked for the ESTABLISHED state This macro will evaluate as 0 if the connection is not in the ESTABLISHED state and 1 if the connection is in the ESTABLISHED state This macro is useful for connections that call Nopen with the S_NOWA flag so that after requesting a connection the connection can be checked to see if it has been established 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 67 5 6 4 SOCKET HASDATA
17. WERR A hardware error occurred Generally this indicates an error with the network controller Examples initialize all network interfaces main if Ninit lt 0 process error if Portinit lt 0 process error Initialize a specific network interface main 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 53 if Ninit lt 0 process error if Portinit com1 lt 0 process error Page 54 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 5 3 4 Portterm e Description Shuts down one or more network interfaces e Syntax int Portterm char name e Input Parameter name If then all network interfaces for this system will be shut down Shuts down the specified network interfaces Note that all interfaces can be shut down at once or individually The shut down routine will put the network controller into an idle state and restore the interrupt vector associated with the network device driver to its original state The shutdown is reversible Just make another call to Portinit A call to Portterm can be omitted prior to calling Nterm because Nterm automatically calls Portterm o Reference Ninit Nterm Portinit e Return Value O Always returns 0 e Examples shut down all network connections Portterm shut down a specific network connection Portterm com1 2004
18. accepted by the connection in a call to Nwrite 5 6 8 SOCKET RXTOUT e Description Sets the receive timeout for a connection e Syntax SOCKET_RXTOUT conno tout e Input Parameter Conno The connection for which the timeout is to be adjusted Tout The new timeout in milliseconds 5 6 9 SOCKET_IPADDR e Description Provides the IP address of the remote end of a connection e Syntax SOCKET_IPADDR conno e Input Parameter conno The connection for which the remote IP address is to be returned The data type of the result is lid 5 6 10 SOCKET OWNIPADDR Description Provides the IP address of the local end of a connection e Syntax SOCKET OWNIPADDR conno e Input Parameter conno The connection for which the local IP address is to be returned The data type of the result is lid This macro is useful for systems that have more than one network interface The IP address returned will be that of the interface that is used for the connection 5 6 11 SOCKET PUSH e Description Sets the PSH flag on the next outgoing TCP segment 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 69 e Syntax SOCKET PUSH conno e Input Parameter conno The connection for which the next outgoing segment should include the PSH flag The next TCP segment to be written following a call to this macro will have the PSH flag set in the TCP header This is useful for indicating to the TCP on the remote system that al
19. aced into the structure hostent This function is reentrant and is available in many but not all 4 3 BSD implementations e Reference gethostbyname e Return Value 0 IP address could not be obtained l 0 IP address is in the returned structure The hostent structure is defined as follows struct hostent char h_name name for host char h_aliases alias list int h_adartype host address type int h_length length of address char h_addr list list of addresses y e Example if gethostbyname_r testserver hostentp buff sizeof buff 8 errval memcpy char 8 socksav sin_adar char hostentp gt h_addr_list O 4 Page 28 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 8 getpeername e Description Extracts the remote address information for a socket e Syntax int getpeername int s struct sockaddr name int namelen e Input Parameter S Socket identifier Name Structure into which the remote address information should be stored Namelen A pointer to the length of the name structure The getpeername function retrieves the remote address information and stores it in the supplied structure e Return Value 1 Error O Remote address was retrieved e Example struct sockaddr_in socka int rc return value int s socket identifier s socket PF_INET SOCK_DGRAM 0 rc getpeername s struct sockaddr amp socka amp socksize if rc
20. as an Er Raa EEA apa aE ERE ESERE REEERE RES EKE RSA 9 1 7 CONNECTIONLESS PROTOCOL pan nn E in E A ERON 10 2 SOFTWARE INSTALLATION ssssseseseesososossosesoosesososoesessososossesosocsosososoesesocsesososoesessosesosseooseesosososoese 11 3 COMPILING amp LINKING iiss ccsscsscssesccstacseecoesesadesaensacsacesstecnesesacieasassdenesesedsnenesavaossessasnaiapeccoesessdasaenses 12 3 1 USING TOR O NA 12 3 2 USING BC HE Lier A te tn mai Ae 14 4 BSD SOCKET INTERFACE sssenenesenenenenenenenenenenenenenesenensnsesenesesee 18 4 1 ABOUT BSD SOCKETS it E it 18 AE ACME A n a aa 21 GAD 11 hi sta Mantes Bd ones tnt bade Hire ist 22 ELLIS aa 23 4LF ConM ltaiiaii id dis 24 AL TENSO da 26 ARO GC CLNOSTDYNQING ai ER AE ea ere cet ces A di De ie tte 27 4 1 7 gethostbyname_ 7 oo a E E E E E RRE 28 BLS gt BELDCCINAME a aia 29 AASO Sg tsockname iia in dad Seances e IIA ERA E EE ts A Gea E 30 4 1 10 gets kopt SOTSOCKOPE sr dt A A mn en dette een ee dd a 31 4 1 11 LOCH SOCK ED iss Ann A ee nt na tt te 33 4 1 12 USC A diia 34 4 1 13 readsOCket rss Minnie ini nee 35 4 1 14 TOC rss ON 36 4 1 15 FE CVILOM inter paid nr 38 4 1 16 AAA ATT 40 4 1 17 SOLOCISOCKE E iii ia ere rte EA nee dE ic asii 41 4 1 18 Senlis mnt mnt nnl a SE tan headers ess 43 4 1 19 SeRAMSS rte etre Ann tre rene re rene dt dass in en lie dia nn mel ation 45 Page 2 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 20 YAA ORE A do Re an tn 46
21. at it only accepts socket identifiers The optional third argument is used as a pointer for the result There is some variation in how this function is defined in BSD sockets The second argument may be unsigned long and of course the variable arguments are treated differently in non ANSI C e Reference getsockopt setsockopt e Return Value 1 Error 0 Operation successful 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 33 4 1 12 listen e Description Listens for connections e Syntax int listen int s int backlog e Input Parameter S Socket identifier backlog Specifies the number of connections that will be held in a queue waiting to be accepted This value includes connections that are in the SYN_RCVD state and connections that are in the ESTABLISHED state that have not yet been accepted by the application The listen function is part of the sequence of functions that are called to perform a passive open This call puts the socket into the LISTEN state Reference socket bind accept e Return Value 1 Error 0 Success e Example int rc return code int s socket identifier rc listen s 5 if rc lt 0 Print Error calling listen n Page 34 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 13 readsocket Description Receives a message from a socket ID Syntax int readsocket int s char buf int len e Input Parameter s So
22. avior MSG_OOB returns urgent data MSG_PEEK returns information allowing it to be read gain on a subsequent call From Specifies the remote host to which the connection should be made Fromlen Size of the from data structure The recvfrom function allows a connection to be made and a message to be read from the connection The flag MSG_WAITALL is not supported e Reference recv recvmsg e Return Value 1 Error gt 0 Number of bytes received e Example The accept or connect call is not needed here since recvfrom establishes the connection before reading int s1 s2 socket identifiers int rc return code unsigned char bufff BUFFLEN read buffer struct sockaddr_in socka remote host address memset amp socka 0 sizeof socka socka sin_family AF_INET gethostbyname_r hnp amp hostent buff sizeof buff Page 38 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 811 if i1 lt 0 Print s not knownin hnp closesocket s2 return 1 memcpy char 8 socka sin_adadr char hostent h_addr_list O lid_ SZ socka sin_ port htons 1 100 rc recvfrom s2 buff 8 0 struct sockaddr amp socka amp socksize if rc 8 Print Error in recvfromin 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 39 4 1 16 recvmsg e Description Receives a message e Syntax int recvmsg int s msghdr msg int
23. ble 4 1 Routines that Manipulate Socket Options level optname Description IPPROTO IP IP_ OPTIONS Options in IP Header IPPROTO TC TCP_MAXSEG get TCP maximum segment P TCP_NODELAY don t delay send SOL_SOCKET SO BROADCAST permit broadcast SO DEBUG debug flag SO DONTROUTE no routing SO_ERROR get and clear error code SO_KEEPALIVE keepalive probing SO_LINGER linger on close SO OOBINLINE leave URG data inline SO RCVBUF receive buffer size SO SNDBUF send buffer size SO_REUSEADDR local address reuse SO _ TYPE get socket type o Reference fctisocket ioctlsocket e Return Value 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 31 1 Error O Success The optval pointer contains the option value for getsockopt the option was set for setsockopt e Example rc setsockopt s SOL_SOCKET SO_KEEPALIVE 0 0 if rc lt 0 Print Error in setsockopt n Page 32 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 11 ioctlsocket e Description Sets control parameters for a socket e Syntax int ioctisocket int s int request char arg e Input Parameter Ss Socket identifier request Request type SIOCATMARK checks out of bound mark Arg Optional argument arg is assigned 1 if the socket read is at the out of bound mark 0 otherwise arg is of type int The foctlsocket function behaves the same as the regular BSD Sockets iocti function except th
24. cka sin_port htons 1100 rc connect s struct sockaddr amp socka sizeof socka if rc lt 0 Page 24 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 Print Error connecting to remote server n Here you can see that amp socka which is of type sockaddr_in must be cast to a sockaddr since this is what is expected by connect This refers back to the previous discussion on structures and definitions 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 25 4 1 5 fentlsocket e Description Controls socket flags e Syntax iint fcntlsocket int s int cmd int arg e Input Parameter S Socket identifier The networking commands are F_GETFL get flags F_SETFL set flags This should of course be fentl but we append socket to this to avoid naming conflicts The fentlsocket function allows a socket to be set to use non blocking semantics and also allows the current setting to be retrieved Networking uses only one flag FNDELAY or O_NDELAY both names seem to be in use for non blocking I O e Reference Non blocking sockets in Chapter 5 Dynamic Protocol Interface e Return Value The return value is 1 for error O for successful SETFL the current value of the flags for successful GETFL Page 26 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 a 6 gethostbyname e Description Returns the IP address that corresponds to a host na
25. ckaddr amp socka sizeof socka if rc lt 0 Print Error sendingin Page 46 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 21 shutdown e Description Shuts down part of a connection e Syntax int shutdown int s int how e Input Parameter s Socket identifier how Describes type of shutdown 0 shuts down receive data path 1 shuts down send data path TCP sends FIN 2 shuts down send and receive path The shutdown function is useful for fully specifying the limited closure of a connection Normally the closesocket function is used to fully close a connection Reference closesocket e Return Value 1 Error 0 Shutdown successful 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 47 4 1 22 socket e Description Creates a socket e Syntax int socket int domain int type int protocol e Input Parameter Domain this should always be PF_INET type one of three constants is for this parameter SOCK_STREAM stream socket TCP IP SOCK_DGRAM datagram socket UDP IP SOCK_RAW raw protocol interface protocol This can be specified as 0 A call to socket will create a socket of the specified type A socket must be created before any other socket calls are used eo Reference closesocket e Return Value 1 Error gt 0 The newly created socket can be accessed through this handle If socket returns with an error indication the value in errno or obtained thro
26. cket identifier buf Buffer into which received data will be stored len Maximum number of bytes to be received The readsocket function behaves the same as the regular BSD Sockets read function except that it only accepts socket identifiers e Reference recv recvfrom recvmsg e Return Value 1 Error gt 0 Number of bytes received 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 35 4 1 14 recv e Description Receives a message e Syntax int recv int s char buf int len int flags e Input Parameter s Socket identifier buf Buffer into which received data will be stored len Maximum number of bytes to be received flags Allows for these options MSG_OOB returns urgent data MSG_PEEK returns information allowing it to be read again on a subsequent call The flag MSG_WAITALL is not supported Reference recvfrom recvmsg e Return Value 1 Error gt 0 Number of bytes received The following error codes could be returned in errno or through getsockopt if recv returns indicating an error EWOULDBLOCK Only returns if the socket is set up as non blocking If thisis the case then a call to recv can check for EWOULDBLOCK and try again later effectively polling EWTIMEDOUT Would only be returned if previously the macro SOCKET_RXTOUT was used to adjust the receive timeout of the socket The application could call recv Jagain later EOPNOTSUPP 1 The call to recv asked for out of ban
27. ctions if Ninit lt 0 process error 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 51 5 3 2 Nterm e Description Shuts down networking e Syntax int Nterm void Nterm takes no parameters Any open network interfaces will be shut down so Portterm does not need to be called before Nterm Network support can be restarted by making a call to Ninit o Reference Ninit Portinit Portterm e Return Value O Always returns 0 e Example shut down all network connections Nterm Page 52 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 5 3 3 Portinit Description Initializes one or more network interfaces Syntax int Portinit char name Input Parameter name If then all network interfaces for this system will be initialized Portinit initializes the specified network interfaces Note that all interfaces can be initialized all at once or individually The initialization routine will prepare the device driver to transmit and receive network frames and will install and enable the interrupt service routine for the network device driver Reference Ninit Nterm Portterm Return Value NE PARAM Parameter error The device driver did not accept the initialization string specified in tcpip lib EHOSTUNREACH The specified port when is not used is not in tcpip lib for this host This could also mean that the host name is wrong NE H
28. d data the flags parameter had MSG_OOB set and none was available 2 The call to recv didn t ask for out of band data and there is some that needs to be received EBADF Invalid socket handle No need to close since that call would return an error as well ECONNABORTED A definite fatal error Usually results from a retransmission timeout or Page 36 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 reception of a RST segment Time to close the socket e Example int rc return code int s1 s2 socket identifiers unsigned char buff BUFFLEN read buffer 52 accept s1 struct sockaddr amp socka amp socksize rc recv s2 buff 2 0 if rc lt 0 Print Error receiving data n else if rc 2 Print Success read 2 bytesin else Print Error did not retrieve 2 bytes n Notice in this example that recv uses the second socket identifier the one returned from the accept not the original socket which is used as an argument to accept 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 37 4 1 15 recvfrom Description Receives a message from a connection e Syntax int recvfrom int s char buf int len int flags struct sockaddr from int fromlen e Input Parameter Ss Socket identifier buf Buffer in which information will be stored len Number of bytes to receive Flags Specifies optional beh
29. ddress of remote system protoc String specifying the transport and network layer protocols separated by a slash Typical values would be TCP IP UDP IP or ICMP IP Ip Local port number For an active open this is often an ephemeral port and a suitable random value can be obtained using the utility function Nportno For a passive open the well known port number should be used rp Remote port number For an active open this should be the well known port for the service used in the connection For a passive open this value should be specified as 0 and any remote port will be accepted for the connection flags Normally O but for a non blocking open you can specify the flag S_NOWA and the call will return without blocking In order to determine if the connection is established use the macro SOCKET_ISOPEN Also for UDP connections you can use the value S NOCON to cause the connection to behave in a connectionless manner When you specify S NOCON the connection will accept all UDP messages directed to the local port regardless of the originating IP Page 58 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 address or UDP port This information is stored so that a call to Nread followed by a call to Nwrite will respond to the source of the message that was just read Nopen is used for both active and passive opens The behavior is determined by the parameters supplied to the functio
30. dentifier name Structure that identifies the remote end of the connection The sin_family member of the structure can be left as O to accept connections on any attached network interface Namelen Size of name A server application uses the bind function to specify the local Internet address and port number for a connection The port number is the port that the server will be listening on A call to bind can also optionally be called by a client application before calling connect Reference socket listen accept closesocket Return Value 1 Error 0 Success The Internet address and port number have been associated with the local end of the socket Example int rc return code int s socket identifier struct sockaddr_in socka local port etc memset amp socka 0 sizeof socka socka sin family AF_INET socka sin_ port htons 1100 rc bind s struct sockaddr amp socka sizeof socka if rc lt 0 Print Error in bind n In this example 1100 is the local port number to be used A client performing a connect to this server would also use port number 1100 Page 22 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 3 Closesocket e Description Closes a socket e Syntax int closesocket int s e Input Parameter S Socket identifier The closesocket function is used to close a socket This function is the same as the regular BSD Sockets close
31. e Description Checks to see if a message is available on a connection e Syntax SOCKET HASDATA conno e Input Parameter conno The connection that should be checked for an available message This macro will evaluate as 0 if no information is available or nonzero if data is available 5 6 5 SOCKET CANSEND e Description Checks to see if a connection can accept data to be written e Syntax SOCKET HASDATA conno len e Input Parameter conno The connection that should be checked for room for writing len The amount of data to be written This macro will evaluate as 0 if the amount of data is more than can be written out immediately or non zero if the data length specified can be written 5 6 6 SOCKET TESTFIN e Description Checks to see if the remote end of the connection has closed e Syntax SOCKET_TESTFIN conno e Input Parameter conno The connection that should be checked for a close from the remote end This macro will evaluate as 0 if the remote end of the connection has not yet closed or non zero if the remote system has closed 5 6 7 SOCKET MAXDAT e Description Provides the maximum size of a buffer than can be Page 68 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 written to a connection e Syntax SOCKET MAXDAT conno e Input Parameter conno The connection for which the maximum buffer size should be determined This macro will evaluate to the maximum number of bytes that can be
32. e set to n 1 readfds Socket identifiers for which selectsocket should return if data becomes available or the state of the socket changes writefds Socket identifiers for which selectsocket should return if the socket can accept more data or if there is an error exceptfds Socket identifiers for which selectsocket should return if out of band data is available timeout Specifies time after which selectsocket will return if none of the specified conditions occurs This is a general UNIX routine but handles sockets as well as files The fd_set structures specify which sockets range 0 to nfds 1 are considered These macros can be used to manipulate fd set FD_ZERO amp fd_set clears the socket list FD_SET s amp fd_set adds socket s FD_CLR s amp fd_set removes socket s FD_ISSET s amp fd_ set non zero if s included When selectsocket returns there are bits in the fd set structures only for those sockets that satisfied the condition Structure timeval gives the timeout value struct timeval Time out format for select long tv_sec seconds long tv_usec microseconds 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 41 A NULL pointer means an infinite timeout If the structure contains the value 0 then the descriptors will be checked once and the call to selectsocket will return without delay This is useful for application level polling e Return Value 1 Error
33. ed DHCP Dynamic Host Configuration Protocol The protocol used by a host to request an IP address from a DHCP server based on the host s name DNS Dynamic Name Server This is a machine which tells remote hosts what their names are based on their IP addresses DPI Dynamic Protocol Interface This is primary interface using stream I O like function calls FTP File Transport Protocol FTP is used to transfer files using TCP connections through port 21 on an FTP server Passive Open passive open means a host attempts to open a connection to any remote host wishing to establish a connection The host will remain in the Nopen function indefinitely until a connection is established TCP Transmission Control Protocol TCP is a reliable protocol that insures data is actually received at the remote site TFTP Trivial File Transport Protocol TFTP is used to transfer files via a UDP connection through port 69 on a TFTP server UDP User Datagram Protocol UDP is a protocol designed to send data packets to the remote site without guaranteeing reception 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 73
34. he basic hardware of the I 7188EN is similar to the 7188EX Since there are too many Configurations for the 1 7188EN series product an OEM or ODM version is welcomed Page 6 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 7 14 TCP IP 4 layer model 4 Application Layer TELNET FTP SMTP DNS 8 Transport Layer TCP UDP gt 2 Network Layer IP ICMP ARP RARP 1 Physical Layer Packet radio Ethernet Figure 1 TCP IP protocol suite using a 4 layer model 1 5 Internet Address 7 bits lt 24 bits class A Of NetID Host ID e 14 bits lt 16 bits gt dse of New ros et 21 bits 8 bits asc Oo so fon e 28 bits casd Oo Mes Figure 2 Internet Address Page 8 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 Network Mask Class A 255 0 0 0 Class B 255 255 0 0 Class C 255 255 255 0 Class D Multicast address 16 Connection Oriented Protocol Server Client socket socket listen connection required scent coment connection established blocks until connection from client Client side data sent for example How are you Server side reply For example Fine thank you Figure 3 Connection Oriented Protocol TCP 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2
35. hernet interface to their products either for use with local networks or for connecting to the Internet Solutions to this problem include both hardware and software Connecting via Ethernet requires a software protocol called TCP IP The installed base of Ethernet networks is vast and growing quickly Most office buildings factories and new homes have an installed Ethernet network With Ethernet the network is always available Using Ethernet for network in industrial areas is appealing because the required cabling is already installed The 7188E series are a series of embedded controllers designed to meet the most common requirements of Internet Ethernet applications They can be used to replace the PC or PLC for the harsh environment The 7188E series provide one on board 10BASE T port that is directly driven by a NE2000 compatible Ethernet controller The 1OBASE T port is equipped with a RJ 45 connector The 10BASE T interface supports the max cable length 100 meters between 7188E amp a hub To link the 7188E amp the other device through a 10BASE_T hub simply use two straight through cables one cable connects to 7188E the other cable connects the hub to the other device 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 5 13 The 7188EX 7188EA amp 7188EN Series The 1 7188EX is powered by a 80188 40 processor with 512K bytes of static RAM and 512K bytes of Flash memory One serial RS 232 port and
36. it is reasonable to write out small buffers directly o Reference Nclose Nopen Nread e Return Value count Values gt 0 indicate the number of byteswritten EBADF The connection number is not valid ETIMEDOUT Timeout With TCP in blocking mode this probably means the other end did not send acknowledgments as expected lt could also mean an extremely heavy system load and that a timeout occurred before the acknowledgment could be received The connection should be closed In nonblocking mode the write should be retried ECONNABORTED Protocol problem Normally the application should close the connection EMSGSIZE The message is too large for the internal buffer e Example user defined output buffer size define MAX_BUFFER_SIZE 80 int error error code Page 64 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 int conno connection Number char buff MAX_BUFFER_SIZE data output buffer write data stored in buff to connection number conno ve error Nwrite conno buff sizeof buff if error lt 0 process error dynamically sized write buffer int error error code int conno connection Number int maxwrite maximum write size char buff MAXBUF data buffer write data stored in buff to connection number conno a conno Nopen host TCP IP Noortno 1050 0 if conno lt 0 process erro
37. l internally buffered segments up through this segment should be delivered to the application as soon as possible 5 6 12 SOCKET FIN e Description Sets the FIN flag on the next outgoing TCP segment e Syntax SOCKET_FIN conno e Input Parameter conno The connection for which the next outgoing segment should include the PSH flag The next TCP segment to be written following a call to this macro will have the FIN flag set in the TCP header This is useful for shutting down a connection at the same time that the last segment is sent Following the write call Nclose to finish closing the connection Nclose will not send a FIN segment in this case e Examples The following text provides examples of e Broadcasting e Non Blocking Operations Broadcasting Example For broadcasting messages to all hosts on the network use host name in the active open and then do an Nwrite For instance host1 conno Nopen enet UDP IP 1010 1000 0 stat Nwrite conno buf len In this case enet is the portname for the network and represents all hosts The receiving hosts open would generally be a passive open Page 70 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 host2 conno Nopen UDP IP 1000 0 0 stat Nread conno buf len The receiving hosts must be listening on the same port number that the broadcasting host is sending to e g 1000 in this ca
38. lt 0 Print Error in getpeernameln 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 29 4 1 9 getsockname e Description Extracts the local address information for a socket e Syntax int getsockname int s struct sockaddr name int namelen e Input Parameter S Socket identifier Name Structure into which the local address information should be stored Namelen A pointer to the length of the name structure The getsockname function retrieves the local address information and stores it in the supplied structure e Return Value 1 Error 0 Local address was retrieved e Example struct sockaddr_in socka int rc return value int s socket identifier s socket PF_INET SOCK_DGRAM 0 rc getsockname s struct sockaddr amp socka amp socksize if rc lt 0 Print Error in getsocknameln Page 30 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 10 getsockopt setsockopt Description Gets and sets options on sockets e Syntax int getsockopt int s int level int optname char optval int optlen int setsockopt int s int level int optname char optval int optlen e Input Parameter S Socket handle level See Table 4 1 below Optname See Table 4 1 below Optval Pointer to option value Optlen Pointer to the size of the data stored in optval The functions in the following table manipulate socket options Ta
39. me e Syntax struct hostent gethostbyname char name e Input Parameter name The name of the host for which the IP address should be obtained The gethostbyname function is not reentrant The gethostbyname_r function should be used in situations where reentrancy is a requirement The name is normally of the form hostname but host network can be used when you want to talk using a specific port or network connection e Reference gethostbyname_r e Return Value O IP address could not be obtained l 0 IP address is in the returned structure e Example hostento gethostbyname testserver if hostentp 0 memcpy char 8 socksav sin_adar char hostentp gt h_addr_list 0 4 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 27 se 7 gethostbyname_r e Description Returns the IP address that corresponds to a host name e Syntax struct hostent gethostbyname_r char name struct hostent result char buff int buflen int errcod e Input Parameter name The name of the host for which the IP address should be obtained Result Structure in which the IP address should be stored buff Scratch buffer which should provide at least 32 bytes Buflen Size of buff Errcod Return code from function The name is normally of the form hostname but host network can be used when you want to talk using a specific port or network connection The IP address of the host is pl
40. msg sends a message that can be split between buffers sendto establishes a connection and sends a message setsockopt sets options on sockets described with getsockopt shutdown shuts down part of a connection socket creates a socket writesocket sends a message to a socket Most functions return a value of 1 in case of an error The error code is stored in errno and can also be retrieved using the getsockopt function as in the following example int errcode errlen il connect s struct sockaddr amp socka sizeof socka if 11 lt 0 il errno if getsockopt s SOL SOCKET SO ERROR amp errcode amp errlen gt 0 11 errcode Print connect error d n i1 additional error handling Here the value of errno is saved before calling getsockopt in case this call fails and causes errno to be overwritten The getsockopt function should be used when possible in multitasking systems because errno is not reentrant If a call to socket returns 1 there is no socket number to refer to when trying to retrieve the error code In this case the error code must be retrieved from errno The gethostbyname functions return a pointer to a host data structure If these functions fail then a null pointer is returned Page 20 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 4 1 1 Accept e Description Accepts a connection on a socket e Syntax int acce
41. n Several examples follow to further illustrate the use of the function passive open will wait indefinitely An active open for TCP will return when the connection has been made but it times out in a couple of minutes if there is no answer Reference Nclose Nread Nwrite e Return Value conno A return value gt 0 is a connection number This is the handle for further communication on the connection EHOSTUNREACH Could not access the remote system ENOBUFS NCONNS in tepip h is not large enough ETIMEDOUT Timeout ECONNABORTED Remote host refused the connection e Examples An active open from host1 that causes TCP to send out open requests to port 1000 The local port number is dynamically and randomly assigned with the function Nportno host1 int conno myport connection and port number myport Nportno conno Nopen host2 TCP IP myport 1000 0 if conno lt 0 process error A passive open at host2 that waits for and accepts calls from anyone who asks for port number 1000 This type of 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 59 open would be done by a server host2 int conno connection number conno Nopen TCP IP 1000 0 0 if conno lt 0 process error A UDP open at host1 for hostA through port com1 would look like this host1 conno Nopen hostA com1 UDP
42. one RS 485 port are provided The Ethernet support is provided by a NE 2000 compatible controller with 16K bytes of on chip buffer memory and 10Base T media interface The I 7188EX also provides 14 user defined I O lines A cost effective I O expansion board with A D D A relays drivers and protected inputs are available The 1 7188EX also supports a battery backup SRAM board and Flash Rom board providing non volatile mass storage from 128K bytes megabytes to 64 megabytes The 10BASE T port is equipped with a RJ 45 connector The 10BASE T interface supports a max of 100 meters of Cable length between the I 7188EX and the network hub Compared to the I 7188EX the I 7188EA adds seven open collector output channels and six digital Input channels The I O Expansion bus has been occupied by a D I O expansion board The 1 7188EX Embedded Internet Ethernet Controller focuses on embedded control applications while the 1 7188EN Internet Communication Controller focuses on communication applications and applications dependant on different embedded firmware programs The Internet Communication Controller can be used as Device Server Addressable Ethernet to RS 232 485 422 Converter or Embedded Internet Ethernet Controller The user should refer to the comparison table to choose the product that best suit their needs Currently we offer a wide range of Internet Communication Controllers such as the 7188E1 E2 E3 E4 E5 E8 Except the RTC circuitry t
43. ons Page 56 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 5 5 Open Close Read and Write These four routines plus the startup and shutdown are the only user level network functions required to write an application using the Library This might surprise you especially if you have seen network packages that go something like call TCPwrite call Ipwrite call DRIVERwrite The library uses a table driven protocol stack structure Each protocol level has only one public symbol The name of the protocol table The library performs all necessary calls through these protocol tables The user only has to call a general high level function that is the same for all protocol configurations The open function specifies which protocols and in which order are to be used There are no restrictions on the protocol stack as such but of course not all combinations make sense Connections 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 57 5 5 1 Nopen e Description Opens a connection e Syntax int Nopen char to char protoc int Ip int rp int flags Input Parameter to String specifying the name of the remote system This can take one of the following forms host Remote host shortest route host network Remote host using named network ae Any host used for passive open or broadcast network Any host using named network n1 n2 n3 n4 IP a
44. pt int s struct sockaddr name int namelen e Input Parameter Ss Socket identifier name On return this provides information about the remote end of the connection Namelen On entry this is a pointer to an integer containing the size of the name structure and on return this pointer points to the size of the returned structure This size will not change The accept call is used by a server application to perform a passive open for a socket The socket will remain in the LISTEN state until a client establishes a connection with the port offered by the server The return value from this function is an identifier for a newly created socket over which communication with the remote client can occur The original socket remains in the LISTEN state and can be used in a subsequent call to accept to provide additional connections Reference socket bind listen e Return Value 1 Error gt 0 Socket identifier for the established connection e Example ints1 s2 int socksz struct sockaddr_in socka socksz sizeof socka memset amp socka 0 sizeof socka socka sin family AF_INET s2 accept s1 struct sockaddr amp socka amp socksz if S2 lt 0 Print Error in acceptin 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 21 4 1 2 Bind Description Binds a name to a socket Syntax int bind int s struct sockaddr name int namelen Input Parameter Ss Socket i
45. r maxwrite SOCKET_MAXDAT conno error Nwrite conno buff maxwrite if error lt 0 process error 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 65 5 6 Dynamic Protocol Interface Macros The following macros are useful for obtaining additional information or setting control information for a connection and are described in this section e SOCKET_NOBLOCK sets the connection for non blocking operation e SOCKET_BLOCK sets the connection for blocking operation e SOCKET_ISOPEN checks to see if a connection has entered the ESTABLISHED state e SOCKET_HASDATA checks to see if a message is available on a connection e SOCKET_CANSEND checks to see if a connection can accept data to be written e SOCKET_TESTFIN checks to see if the remote end of the connection has closed e SOCKET_MAXDAT provides the maximum size of a buffer than can be written to a connection e SOCKET_RXTOUT sets the receive timeout for a connection e SOCKET_IPADDR provides the IP address of the remote end of a connection e SOCKET_OWNIPADDR provides the IP address of the local end of a connection e SOCKET_PUSH sets the PSH flag on the next outgoing TCP segment e SOCKET_FIN sets the FIN flag on the next outgoing TCP segment Connections Page 66 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 5 6 1 SOCKET NOBLOCK e Description Sets the connection for non blocking operation e Syntax SOCKET_N
46. s Example viccsceccecisiecstessccssnsiscvedveteesssdessesuscusbevasesasepesseceessvuoueosesdeebuseancasugadeesveeeiees 71 APPENDIX A OOOO 73 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 3 1 Introduction 1 1 Package List 8 Release Notes Package List In addition to this manual all packages includes the following items One 7188E hardware module One user s manual this manual One release note One software utility disk or CD One download cable CA0915 Note If any of these items are missing or damaged contact the local distributors for more information Save the shipping materials and cartons in case you want to ship in the future Release Note It is recommended to read the release note amp README TXT first The release note is given in the shipping The README TXT is given in the CD README TXT Some important information are given in the release note amp CD README TXT Order Information Call distributor for details Page 4 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 12 Why Ethernet Solutions Embedded Internet and Embedded Ethernet are hot topics today Nowadays the Ethernet protocol has become the de facto standard for local area networks Via the Internet connectivity is spreading into many different areas from home appliances to vending machines from testing equipment to UPS etc Many embedded designers now face dilemma of adding an Et
47. se Broadcasting should only be used for data links that support it in hardware such as Ethernet It should not be done at the TCP level If the broadcasting host connects to several networks the open call must specify the network name Broadcasting is done to one network only Examples Non Blocking Operations Example The following example shows how to read using non blocking operations Non blocking writes will complicate an application quite a bit If no multi task is used there is really no alternative to non blocking operations With multitasking a heavy use perhaps even any use of non blocking mode is not recommended conno Nopen TCP IP 1001 0 S NOWA if conno lt 0 ERROR Y while ISOCKET_ISOPEN conno perform other work YIELD SOCKET_NOBLOCK conno for YIELD len Nread conno buf sizeof buf if len lt 0 if len EWOULDBLOCK break error else perform other work 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 71 else if len 0 break other end closed else process message stat Nclose conno if stat lt 0 ERROR Page 72 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 Appendix Glossary CHAP Challenge Handshake Authentication Protocol user and password authentication method used by a PPP connection Both the user name and password are encrypt
48. t significant To support these users we have made the sockets as similar to 4 3 BSD sockets as reasonably possible These points may require special attention e Symbolic error codes are not perfectly standardized across different UNIX systems ICPDAS uses the Solaris names e The typical UNIX use of errno is not reentrant If this becomes critical use getsockopt to get the last error code e The function gethostbyname is not reentrant Use gethostbyname_r instead if this is critical e You can t mix files and sockets For instance you can t use a selectsocket to wait for either a keyboard character or a network packet e Avoid non blocking mode if multitasking is used Structures and Definitions Many of the BSD socket routines use a pointer to structure sockaddr which specifies network address information The sockaddr structure is a generic structure that can be used with a number of different communications protocols ICPDAS only uses the Internet Protocol IP and therefore only requires the use of the Internet structure sockaddr_in Values are assigned to sockaddr_in and passed into the socket routine via the sockaddr parameter This requires a typecast to sockaddr The discussion of the connect function provides an example Here are the structure definitions struct sockaddr generic socket address Page 18 7 188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 unsigned short sa_ family
49. ugh getsockopt can be interpreted as follows EPROTONOSUPPORT The requested protocol is not available Perhaps SOCK_STREAM was specified but TCP support is not configured for the underlying stack e Example int s a socket s socket PF_INET SOCK_DGRAM 0 if S lt 0 Print Error opening socket n Page 48 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 1 0 2001 07 41 23 writesocket e Description Sends a message to a socket e Syntax int writesocket int s char buf int len e Input Parameter s Socket identifier buf Pointer to data to be sent len Number of bytes to send The writesocket function behaves the same as the regular BSD Sockets write function except that it only accepts socket identifiers Reference send sendto sendmsg Return Value 1 Error gt 0 Number of bytes sent 2004 11 7188E 843X 844X 883X 884X TCP IP Library User s Manual Ver 2 0 Page 49 5 Dynamic Protocol Interface 5 1 Overview This Chapter details the usage of ICPDAS Dynamic Protocol Interface The Dynamic Protocol Interface provides a simple and efficient interface to implement the Networking program 5 2 Blocking Versus Non Blocking Operation There are two modes of operation that affect how your application deals with network events in a non multitasking system Blocking and non blocking Blocking is the default mode This mode will halt processing while waiting for a network event to complete

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