Applications of M16C/62 Flash CPU Rewrite Mode
Contents
1. N all flash hour bits programmed 4 determine word in flash hour block to program WRITE HOURS OF determine offset of word from O P E RAT O N page boundary FROM FLASH Vv determine bit in word to program vy fill buffer with blanks y insert word into buffer at offset v determine flash page to write buffer to y Code in RAM set command PAGE_PROGRAM_ Call ramcode 4 7 Me OO exit P Figure 17 Write Hours of Operation from Flash Flowchart REU05B0014 0100Z June 2003 Page 22 of 22 Keep safety first in your circuit designs Renesas Technology Corporation puts the maximum effort into making semiconductor products better and more reliable but there is always the possibility that trouble may occur with them Trouble with semiconductors may lead to personal injury fire or property damage Remember to give due consideration to safety when making your circuit designs with appropriate measures such as i placement of substitutive auxiliary circuits ii use of nonflammable material or iii prevention against any malfunction or mishap Notes regarding these materials These materials are intended as a reference to assist our customers in the selection of the Renesas Technology Corporation product best suited to the customer s application they do not convey any license under any2. June 2003 Page 6 of 22 M16C 62 E Q ENIECSAS Applications of M16C 62 Flash CPU Rewrite Mode 4 2 Demonstrating the Program The program was developed to run on the MSV1632 62 Starter Kit but it also works with any M16C 62 flash system running the KD30 debugger in single chip mode If using a different platform it may be necessary to remove the code that toggles Port P7 7 Follow these steps to run the Demonstration assumes user has a general understanding of the KD30 debugger Connect the MSV1632 62 board to a power source and the host PC Start KD30 In the INIT screen click on the tab run mode and select free run mode Load the flashapp x30 file Open three memory windows to view the flash Basic Window gt Dump Window a FF wn gt Configure the windows to view the flash addresses used in the demo click on any number in the address column and enter FOO00h F8000h and C0000h for each window Note the FO000h and CO0000h flash blocks are blank all FF s and the constants are in the F8000h block scroll down to see the character constants Insert a breakpoint in the main function at the getvarfromflash line Run the code debug gt go free Hit the red stop button on KD30 in free run mode KD30 does not respond automatically to breakpoints View the memory at FO000h and COOOOh Note the test variables were saved to the beginning of the FOO00h block and that block was copied t
3. M16C 62 x g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode block lock write Set command 77h Set address last word address of block calling function Call ramcode code in ROM v A ramcode startup sequence x code in RAM y M address lt 77h A ramcode exit sequence code in RAM v A code in ROM y ee C return Figure 9 Block Lock Write Flowchart REU05B0014 0100Z June 2003 Page 14 of 22 M16C 62 Q ENIECSAS Applications of M16C 62 Flash CPU Rewrite Mode clear SRD Set command 50h Call ramcode calling function code in ROM v A ramcode startup sequence code in RAM write 50h to M FOOOOH ramcode exit sequence code in RAM v A code in ROM Figure 10 Clear SRD Flowchart REU05B0014 0100Z June 2003 Page 15 of 22 M16C 62 g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode read SRD calling function Set command Call Ramcode code in ROM v A ramcode startup sequence code in RAM write 70h to M F0000H SRD lt M F0000H ramcode exit sequence code in RAM v A y exit code in ROM Figure 11 Read SRD Flowchart REU05B0014 0100Z June 2003 Page 16 of 22 M16C 62 g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode get variables from flash rampo
4. intellectual property rights or any other rights belonging to Renesas Technology Corporation or a third party Renesas Technology Corporation assumes no responsibility for any damage or infringement of any third party s rights originating in the use of any product data diagrams charts programs algorithms or circuit application examples contained in these materials All information contained in these materials including product data diagrams charts programs and algorithms represents information on products at the time of publication of these materials and are subject to change by Renesas Technology Corporation without notice due to product improvements or other reasons It is therefore recommended that customers contact Renesas Technology Corporation or an authorized Renesas Technology Corporation product distributor for the latest product information before purchasing a product listed herein The information described here may contain technical inaccuracies or typographical errors Renesas Technology Corporation assumes no responsibility for any damage liability or other loss rising from these inaccuracies or errors Please also pay attention to information published by Renesas Technology Corporation by various means including the Renesas Technology Corporation Semiconductor home page http www renesas com When using any or all of the information contained in these materials including product data diagrams charts programs and
5. 16C 62 E Q ENIECSAS Applications of M16C 62 Flash CPU Rewrite Mode 3 Table 2 lists the callable functions and describes how to use them The functions do not return any error codes and it is up to the user to supply the functions with valid parameters Table 2 Function calls cpurw_ini Saves the current clock settings of the CPU then changes the CPU frequency to f 2 and adds a wait state Not required if operating the CPU below 6 MHz restorestate Returns the CPU s clock settings to the state before calling the function cpurw_ini copy_flash_code Copies the CPU rewrite code all of file RAM62 c to RAM writeconstw long int Writes a word to flash Supply the address long must be an even address and the value to write int copyvartoflash int char Writes variables in RAM to flash Supply the starting address of the variables to copy in RAM int and the ending address in RAM char The differences in pointer types int and char are due to the C compiler putting the integers at the beginning of a section even followed by the characters odd The destination flash block is erased before the copy The destination written in flash is fixed in the function at the start of block 3 FOOOOh getvarfromflash int ramptr char endvars Reads the saved variables from the start of flash block 3 FOOOOH and writes them to RAM Basically it is the reverse of copyvart
6. 653 6 666668 666538 66666a 666542 666662 6665 44 666666 666b44 6663 66 666e44 66F1bc 61 6666 Gbf 666 6c f 666 6666c A 6c f Gc O 616F 46 Be 6666 666169 e 6169 666cca Be 6dd3 666616 Be de3 61721d 6F8 666 666476 6F847 6 666661 6F8471 607b6b 6F FFdc 666624 BFFFFF Figure 3 Example Program MAP View 3 1 2 Writing Relocatable Code in C As noted previously CPU rewrite code cannot execute out of flash but must be moved to RAM The M16C can produce 100 percent relocatable code within a 32k address space The NC30 C compiler generates relocatable code for all functions in the same file within the 32k address restriction This example program utilizes these facts and the source code that executes out of RAM is written in C The C code is compiled and downloaded to flash then the copy_flash_code void copies the code into RAM where it is executed 3 1 3 Writing a Word to Flash While the command to write to flash requires programming a complete page 256 bytes or 128 words it does not suggest that it is impossible to program a word at a time The hours of operations and write constant applications are examples of how to write a word at a time to flash When programming a page if all the data for the page is not available write blanks 1 s to the unused memory in that page 4 0 Demonstration Program 4 1 General Notes The demonstration program is designed to r
7. Methodology 3 1 1 Section Definitions The most transparent method to manipulate the flash within a C program is to define specific memory sections The C language uses sections to distinguish between initialized variables un initialized variables constants and so on The NC30 compiler allows user defined sections in RAM or ROM For this example the standard NC30 start up file sect30 inc is modified and renamed to WFsect30 inc This new file contains two extra sections a flashsave section for saving variables to flash and a parmblock section for writing constants within a user program Figure 3 is the MAP view of the example program Note that the flashsave section is not given an absolute address so it starts right after the bss section Once the section is defined placing the directive pragma SECTION in a file redirects all constants or variables to the new section until the next pragma SECTION or the end of file is reached For efficiency the compiler puts all integers at the start of each section even and the characters odd at the end of each section This is why the labels for the start and end of the flashsave section are integer and character respectively REU05B0014 0100Z June 2003 Page 4 of 22 M16C 62 E Q ENIECSAS Applications of M16C 62 Flash CPU Rewrite Mode Address size Section 666666 666466 gt gt 666466 666616 66641 6 666126 66
8. RENESAS APPLICATION NOTE M16C 62 Applications of M16C 62 Flash CPU Rewrite Mode 1 0 Abstract The following article accompanies the flashapp program It describes using the CPU rewrite mode on the M16C 62 within a user program A set of flash device drivers is included and four application examples are identified copying variables to flash using flash for hours of operation defining and writing constants to flash and copying one flash block to the other Certain techniques may be specific to the Renesas NC30WA C compiler 2 0 Introduction The Renesas M16C 62 is a 16 bit MCU based on the M16C CPU core with 256k bytes of user flash The device can erase and program the on chip flash memory under control of a user s program with no external programming devices required This feature is called CPU Rewrite Mode The M16C 62 has two other flash programming modes Parallel I O Mode and Standard Serial I O Mode Because these modes are mainly for programming the application code into the flash details are not discussed in this article To use CPU Rewrite Mode the memory structure and the control registers need to be identified The memory map of the M16C 62 is shown in Figure 1 Note that the flash is divided into blocks such that certain erase programming functions are done on a block basis The boot flash area is used for serial I O mode and is not available for CPU Rewrite mode programming The Flash Memory Control R
9. algorithms please be sure to evaluate all information as a total system before making a final decision on the applicability of the information and products Renesas Technology Corporation assumes no responsibility for any damage liability or other loss resulting from the information contained herein Renesas Technology Corporation semiconductors are not designed or manufactured for use in a device or system that is used under circumstances in which human life is potentially at stake Please contact Renesas Technology Corporation or an authorized Renesas Technology Corporation product distributor when considering the use of a product contained herein for any specific purposes such as apparatus or systems for transportation vehicular medical aerospace nuclear or undersea repeater use The prior written approval of Renesas Technology Corporation is necessary to reprint or reproduce in whole or in part these materials If these products or technologies are subject to the Japanese export control restrictions they must be exported under a license from the Japanese government and cannot be imported into a country other than the approved destination Any diversion or reexport contrary to the export control laws and regulations of Japan and or the country of destination is prohibited Please contact Renesas Technology Corporation for further details on these materials or the products contained therein
10. ce j code in RAM AA unlock all blocks flash ready AA progptr 0 word address lt 41h Vv word address lt progbuff progptr y progptr progptr 1 address address 2 page done Figure 6 Page Write Flowchart REU05B0014 0100Z June 2003 Page 11 of 22 M16C 62 x g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode block erase Set command 20h Set address last word address of block Call ramcode calling function code in ROM ramcode startup Sequence l code in RAM A AA unlock all blocks AA write erase command to block address write confirm command to block address ramcode exit sequence code in RAM code in ROM Figure 7 Block Erase Flowchart REU05B0014 0100Z June 2003 Page 12 of 22 M16C 62 g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode block lock read Set command calling function 71h Set address last word address of block Call ramcode code in ROM ramcode startup Sequence code in RAM y M address lt 71h lockbitstor lockbit status y ramcode exit sequence code in RAM code in ROM y return Figure 8 Block Lock Read Flowchart REU05B0014 0100Z June 2003 Page 13 of 22
11. code ee return Figure 14 Write Constant to Flash Flowchart REU05B0014 0100Z June 2003 Page 19 of 22 M16C 62 x g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode copy block erase destination block point to start of source block source point to start of destination block destination AA copypointer 0 v flashbuffer copypointer M source increment source lt lt increment copypointer yes flash address destination Code in set command PAGE_PROGRAM Call ramcode RAM y destination destination 256 all of block copied yes return Figure 15 Copy Block Flowchart REU05B0014 0100Z June 2003 Page 20 of 22 M16C 62 x g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode Read hours of operation operating hours 0 all flash hour bit programmed operating hours max of hours get next word from flash hour 4 block is it FFFFh operating hours operating hours 16 operating hours operating hours 1 shift word 1 bit right Figure 16 Read Hours of Operation Flowchart REU05B0014 0100Z June 2003 Page 21 of 22 M16C 62 x g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode Write Hours X
12. egister FMCR is shown in Figure 2 Normally only the first three LSBs are used for CPU rewrite mode Beyond CPU registers the flash memory has its own logic to handle erase and programming procedures This is the flash s Write State Machine WSM The WSM commands are given in Table 1 REU05B0014 0100Z June 2003 Page 1 of 22 M16C 62 E Q ENIECSAS Applications of M16C 62 Flash CPU Rewrite Mode 00000H F OO3FFH 00400H Internal RAM area O53FFH External area Block 6 64K bytes Block 5 64K bytes Block 4 64K bytes Block 3 32K bytes Block 2 8K bytes Block 1 8K bytes The boot flash is not in the 1M linear address space and can only be accessed by coming out of reset in Boot Mode Block 0 16K bytes FEOOOH Fixed vector PROPI 8K byte boot flash area Figure 1 M16C 62 Memory Map b7 b0 Symbol Address At xIx 0 FMRC 03b7H XX000001 i i RY BY flag 0 flash busy FMR00 1 flash ready 0 Normal mode FMRO CPU rewrite bit 1 CPU rewrite mode Lock bits disable bit 0 flash block lock bits in effect FMR02 allow lock bit erase 1 over ride flash block lock bits 0 normal operation FMR03 Abort Current command 1 reset flash FMR05 ROM area select bit 0 boot ROM area is selected effective in boot mode only 1 User ROM area is selected Figure 2 Flash Memory Con
13. inter start of variable section rompointer start of flash block M rampointer M rompointer increment rampointer increment rompointer all variables copied return Figure 12 Get Variables from Flash Flowchart REU05B0014 0100Z June 2003 Page 17 of 22 M16C 62 5 g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode TE variables to flash erase destination block A y rampointer start of variable section flash address start of flash block y copypointer 0 e y flashbuffer copypointer M rampointer increment rampointer A increment copypointer flash buffer full set command PAGE_PROGRAM Code in RAM y Call ramcode a Vv flash address flash address 256 all variables copied yes return Figure 13 Write to Flash Flowchart REU05B0014 0100Z June 2003 Page 18 of 22 M16C 62 x g ENESAS Applications of M16C 62 Flash CPU Rewrite Mode Write constant to flash Set address of constant to write Set value to write buffer offset address of constant amp FFh flash page address address of constant amp FFFFOOh Fill flash buffer with blanks FFFFh flash buffer buffer offset value y Code in RAM Call ram
14. o the CO000h block 2 N 10 Open a memory window Basic window gt memory window and find the testdata in the flashsave section check your map viewer in Tool Manager Double click on the variables and clear them 11 Click go Each time the LED D6 toggles the hour meter is updated about every 5 seconds for demo 12 Right after a toggle click the stop button i e you do not want to attempt to stop while writing to flash 13 Open a C watch window Basic Window gt C watch window gt global window and note the testdata has been copied back from flash and the oper_hrs equals the number of LED toggles 5 0 Implementing the Flash Drivers in a User Program 1 The RAM62 c fdevice h fl_util c and flash h files form the driver Include flash h in any project file that requires driver functions Add RAM62 c and fl_util c to your project These files require the fdriver h header file Review the demonstration program and determine if the application requires user defined sections 2 Before using any CPU rewrite commands call cpurw_ini and copy_flash_code to set the flash operation environment The CPU rewrite code resides in the 512 byte array cpu_rw The actual code is approximately 400 bytes The extra array bytes allow the user to modify the CPU rewrite code REU05B0014 0100Z June 2003 Page 7 of 22 M
15. oflash copyblock void Copies all of block 3 FOOOOh to the start of block 6 C0000h Block 6 is erased before the copy The blocks and addresses are fixed within the function ramcode void This is the CPU rewrite code that executes out of RAM The code must be copied to RAM using copy_flash_code First set the global variable command then call ramcode to execute one of the following flash commands see flash h for command codes erase a block program a page read flash status SRD clear flash status SRD read a block lock bit lock a block Note that the command codes used are the same as those for CPU rewrite codes If a command requires an address put the 32 bit address into the global union uaddr alias addrvar After executing the read SRD command the value is stored in global SRD After reading a block lock bit the value is stored in global lockbitstor The program a page command will write the 256 bytes in the global flashbuff to the address in addrvar REU05B0014 0100Z June 2003 Page 8 of 22 M16C 62 E Q ENIECSAS Applications of M16C 62 Flash CPU Rewrite Mode 6 0 Reference Renesas Technology Corporation Semiconductor Home Page http www renesas com E mail Support support _apl renesas com Data Sheets e 62AEDS pdf M16C 62A Specifications User s Manual e cpurw62 pdf appnote Programming
16. the M16C 62 Flash in CPU Rewrite Mode e 6020esm pdf Software Manual e 6020ec pdf C Manual e 6020easm pdf Assembler Manual e NC30ue pdf Compiler Manual REU05B0014 0100Z June 2003 Page 9 of 22 M16C 62 E Q ENECSAS Applications of M16C 62 Flash CPU Rewrite Mode 7 0 Appendix RAMCODE STARTUP SEQUENCE S turn on CPU Start E rewrite mode decode command CMD gt page program 41H page prog CMD 20H gt block erase note1 turning off CPU rewrite mode disables CMD read status flash block C0000h 70H PL register note2 read array command resets the flash CMD memory 50H clear status register es ead block lock 71H l ig bit CMD 77H program block lock bit o wait for flash la ready sendread array command to flash RAMCODE EXIT __ nofe 2 SEQUENCE wait for flash ready turn oF CPU rewrite mode turn cooboh flash block back on note 1 Figure 5 Code in RAM Flowchart REU05B0014 0100Z June 2003 Page 10 of 22 M16C 62 Q ENECSAS Applications of M16C 62 Flash CPU Rewrite Mode yes page write D y l ramcode exit code in RAM sequence command 41h calling functio Set address naen page code in ROM address exit ramcode startup sequen
17. trol Register REU05B0014 0100Z June 2003 Page 2 of 22 M16C 62 E Q ENICSAS Applications of M16C 62 Flash CPU Rewrite Mode Table 1 Flash Memory Control Register Second bus cycle Third bus cycle Command Data Data Data Mose nates onion Move A tonio bn pee poorer Rears wie xomo ere CS re e a a a e oearsans easter wae x o _ Page proaram mona wate x are wre waoneralwoonsna wee war wor mokos wie x ate wie faeson TP Ese anuro wate x Are wae x oo _ Toacbapregam wae x mre wie ea ooe Reasons wae x me eos ea o Note 1 When a software command is input the high order byte of data De to D15 is ignored Note 2 SRD Status Register Data Note 3 WA Write Address WD Write Data WA and WD must be set sequentially from 0016 to FE16 byte address however an even address The page size is 256 bytes Note 4 BA Block Address Enter the maximum address of each block that is an even address Note 5 D corresponds to the block lock status Block not locked when De 1 block locked when De 0 Note 6 X denotes a given address in the user ROM area that is an even address 2 1 Compatibility This program is compatible with M16C 6x microcontrollers with page write 256 bytes flash memory It is NOT compatible with word write MCUs such as the M16C 62P series The driver is compatible with the above noted MCUs on any Starter Kit eval
18. uation system running under the KD30 debugger It CANNOT be evaluated or demonstrated on any emulator using RAM to emulate flash i e Renesas PC4701 Nohau or Ashling emulator systems 2 2 Flash Programming Basics The M16C 62 s flash must be programmed in 256 byte pages on page boundaries A0 A7 00 FEh 16 bits at a time Attempts to program 8 bit data are ignored and even commands must be set as 16 bit words The flash can be bulk erased erase all unlocked blocks command or erased one block at a time see memory map Bit erase state 1 Once a block is erased individual pages can be programmed at any time The CPU rewrite program can be stored in the flash but because the WSM is common to all flash all blocks the CPU rewrite code cannot execute out of flash The rewrite code must be transferred to RAM before it can be executed 3 0 Application The example program includes 6 basic flash commands 1 Erase a block 2 Program a page 3 Read flash status SRD 4 Clear flash status SRD REU05B0014 0100Z June 2003 Page 3 of 22 M16C 62 E Q ENIECSAS Applications of M16C 62 Flash CPU Rewrite Mode 5 Read a block lock bit 6 Lock a block The program uses these commands to illustrate a few basic applications Save variables to flash amp read them back into RAM Copy the data in one block to another block Write constants to flash PO NS Use the flash for hours of operation 3 1
19. un on the MSV1632 62 board running under KD30 in free run mode but the drivers see RAM62 c are meant for implementation within a user s project Figure 4 shows the flowchart for the main demo function flowcharts for the commands and application calls and given in section 7 0 Appendix The program minimizes passing absolute addresses because it could lead to accidental corruption of flash The REU05B0014 0100Z June 2003 Page 5 of 22 M16C 62 E Q ENESAS Applications of M16C 62 Flash CPU Rewrite Mode main function is in file flashmain c The applications operate on blocks 2 3 and 6 of the flash because block 1 is not available running under the ROM Monitor lt initialize MSA0654 display get saved operating hours time operating hours i start hour timer initalize CPU clock for flash operations vy copy CPURW code to RAM v give variables values write variables to Flash AA copy one flash block to another AA write a constant to flash v restore CPU clock settings copy savedvariabtesto RAM write 00 to display time gt operating hours operating hours operating hours 1 initalize CPU clock for flash operations write hours to flash restore CPU clock settings Figure 4 Demonstration Program Main Flowchart REU05B0014 0100Z
Download Pdf Manuals
Related Search