LPC2148 Education Board User`s Guide
Contents
1. SPIHO4 gt Sigi Lower position connects it to SSP SPI channel 1 Figure 29 10M Ethernet Expansion Board Jumpers The 70M Ethernet Expansion Board power consumption is low enough to let the USB power of the LPC2148 Education Board also feed this expansion board i e no external power supply is needed for this board Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 34 7 App B Bluetooth Expansion Board This chapter contains detailed information about the electrical design of the board 7 1 Board Schematics Sheet 1 4 TITLE Bluetooth Expansion v1 8 Document Number Gaz cho RIOUT RIN R20UT RAN fS U1G 2 IT nov E iD ie T o OnE e D D 1 l Figure 30 Bluetooth Expansion Board Schematic Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 35 The main part of the design is to interface the LPC2148 Education Board to the Bluetooth module from connectBlue The Bluetooth module is unique in the sense that it is a complete product that is Bluetooth qualified all Bluetooth products on the market must be certified to the Bluetooth standard and this is called Bluetooth qualification Products based on these modules from connectBlue do not require any further Bluetooth qualification Download product documentation from connectBlue s homepage for details about the Bluetooth modules http www2. There are two options to reduce the number of pins used for the interface e Do not use the R W pin and save one pin P0 22 Normally there is only a need to write to the display controller In this case the R W signal can be tied low permanently R45 and jumper J38 is removed e Use the 4 bit interface instead of the 8 bit interface The LCD controller can operate from a 4 bit interface In this case data bus pins D4 D7 are just used In this case 4 pins will be free P1 16 P1 19 for other use If combined with the option above five pins will be freed 2 1 18 Page 3 8x8 LED Matrix with SPI Interface The 8x8 LED matrix is the most advanced circuit on the board at least when it comes to controlling it Figure 21 below illustrate the 8x8 LED matrix part of the design Two shift registers serial input parallel output 74HC595 are used to control the eight columns and rows respectively 16 bits must be shifted 2 bytes in order to update the two shift Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 23 registers The first byte sent controls the rows and the second byte the columns A zero bit in the first byte will light LEDs for the corresponding row and a zero bit in the second byte will light LEDs for the corresponding column In order to display arbitrary patterns on the display a time multiplexing mechanism must be implemented where each column or row is updated one at
3. Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide LPC2148 Education Board User s Guide Seeeeeoee 200000 J gt j m GC Ze gt F aa G ZS CD ov D D ki E al Si E Nu 3 3 3 P lt dam Dec hamn tf of UEZ t m Pierro P NW W V 63 64 e De o gt ece cers Mk e Se e Learn everything there is about the new ANM 32 bit MCU s Start Developing Your Applications On Day 1 Embedded Artists EA2 USG 0601 v1 2 Rev B LPC2148 Education Board User s Guide Page 2 Embedded Artists AB Friisgatan 33 SE 214 21 Malm Sweden info EmbeddedArtists com http www EmbeddedArtists com Copyright 2005 2006 Embedded Artists AB All rights reserved No part of this publication may be reproduced transmitted transcribed stored in a retrieval system or translated into any language or computer language in any form or by any means electronic mechanical magnetic optical chemical manual or otherwise without the prior written permission of Embedded Artists AB Disclaimer Embedded Artists AB makes no representation or warranties with respect to the contents hereof and specifically disclaim any implied warranties or merchantability or fitness for any particular purpose Information in this publication is subject to change without notice and does not represent a commitment on the part of Embed
4. Jas 0000 uBAT UREF_IN ureF ussa poa po 4 pa 2 po 3 po 4 pas Figure 31 Bluetooth Expansion Board Jumpers Note that the rest control of P0 14 is not active The transistor base resistor is not mounted Communication status is indicated via a RGB LED See the module s documentation for details The Bluetooth module is powered with 3 3V from the LPC2148 Education Board USB powering of the LPC2148 Education Board is typically possible since the peak current consumption of the Bluetooth module is 150 mA peak current is 70 mA for OEMSPA311i Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 36 8 App C Graphical LCD Expansion Board This chapter contains detailed information about the electrical design of the board 8 1 Board Schematics Sheet 1 1 S d gt c E a 4 D x j 8 fe D 2 E E Document Number Figure 32 Graphical Expansion Board Schematic Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 37 The graphical monochrome display has 240x128 pixels and contains an on board LCD controller based on T6963C from Toshiba The controller has a standard 8 bit parallel MCU interface The LPC2148 must simulate this interface since it has no external address databus 13 pins are needed to create an 8 bit interface 8 data bits DO D7 1 ad
5. The Prototype Expansion Board allows you to build your own design and interface it to the LPC2148 Education Board All signals on the expansion connector can easily be accessed The board contains a large 100 mil prototype area a smaller 50 mil prototype area two 50 mil areas for SOIC chips and a 0 65 mm area for SSOP chips Solder pads for bypass capacitors are placed between the solder pad rows for the SOIC areas It is possible to feed these bypass capacitors with either 3 3V or 5V selectable via two jumpers See electrical schematic above Copyright 2006 Embedded Artists AB
6. Gun AOUT PAD7 GND Figure 19 LPC2148 Education Board Schematic page 3 Analog Outputs 2 1 17 Page 3 2x16 Character LCD The LPC2148 Education Board also contains a small 2x16 character LCD The interface to the LCD is a simulated memory bus 11 pins are needed to create an 8 bit interface 8 data bits DO D7 1 address bit RS 1 read write bit R W and one control signal E It s also Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 22 possible to control the backlight via signal P0 30 The LCD controller is a standard KS0070B or equivalent which is a very well known interface for smaller character based LCDs Figure 20 below illustrate the LCD part of the design and which pins are used for the interface All pins can be disconnected from the interface if needed via jumpers J25 J32 and J38 J41 The LCD is powered from the 5V power supply but there is an option to power it from the 3 3V power supply 5V power is no problem since all pins on the LPC2148 are 5V tolerant and a high logic level from the CPU powered by 3 3V is also interpreted as a high logic level by the LCD Display contrast is adjusted via trim potentiometer R53 2x16 Character LCD Interface Q mI Ee EE Pe E 0 30 ail i S Ge a 0 mdo not mount 100nF S VM LS Ofo N O AE LLELE se OCDE DOUD Figure 20 LPC2148 Education Board Schematic page 3 2x16 Character LCD
7. J31 D6 P1 22 J32 D7 P1 23 J41 backlight P0 30 8x8 LED Matrix In order from top to bottom J24 MOSI P0 6 J33 SCK P0 4 J37 Select P0 15 J42 MISO P0 5 C 2005 Emb uvu Embedde LPC2138 48 J16 P0 7 Motor Control Analog Inputs Analog Output LEDs In order from left In order from left J23 P0 30 AIN3 In order from left to right to right Left pos PWM LP to right J49 Enable P0 10 J18 P0 28 AIN1 Right pos AOUT P0 25 J54 P0 15 J53 PWM6 P0 9 J15 P0 29 AIN2 J52 P0 14 J51 PWM4 P0 8 J50 P0 13 J48 P0 12 J47 P0 11 J46 P0 10 J44 P0 9 J43 P0 8 Figure 24 LPC2148 Education Board Jumpers 2 2 1 Illegal Jumper Combinations Note that some jumpers are mutual exclusive and should not be inserted simultaneously e MISO signal P0 5 on SPI channel 0 Do not have jumper J42 inserted simultaneously as the MMC SD interface is used See explanation in section 2 1 13 e P0 7 is a commonly used signal that is used for the buzzer motor control the red LED in the RGB LED individual LED and the servo motor interface Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 26 e Many of the signals for the individual LEDs P0 8 P0 15 are also used for other parts of the design It does not damage the electronics if the LEDs are connected and in some cases it mig
8. 26 2 4 Important Components 27 2 5 Mechanical Dimensions 28 2 6 JTAG Interface and Reset Control Issue 28 3 Getting Started 29 3 1 Test program 29 3 2 Program Development 29 4 CD ROM and Product Registration 30 4 1 CD ROM 30 4 2 Product Registration 30 Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 4 5 Further Information 31 6 App A 10M Ethernet Expansion Board 32 6 1 Board Schematics 32 7 App B Bluetooth Expansion Board 34 7 1 Board Schematics 34 8 App C Graphical LCD Expansion Board 36 8 1 Board Schematics 36 9 App D UART amp RS485 Expansion Board 38 9 1 Board Schematics 38 10 App E MP3 Decoder Expansion Board 40 10 1 Board Schematics 40 11 App F ZigBee Expansion Board 42 11 1 Board Schematics 42 12 App G Prototype Expansion Board 44 12 1 Board Schematics 44 Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 5 1 Introduction Thank you for buying Embedded Artists LPC2148 Education Board based on Philips ARM7TDMI LPC2148 microcontroller This document is a User s Guide that describes the LPC2148 Education Board hardware design and some basic software interface principles with the hardware There is a separate document describing program development that also includes a lot of experiments that will guide you through the art of embedded program development 1 1 Contents The box received when ordering the LPC21
9. Artists AB LPC2148 Education Board User s Guide Page 28 2 5 Mechanical Dimensions Figure 27 below contains a drawing of the board that includes mechanical measures As seen the board is 139 x 110 mm large with mounting holes 125 x 98 mm apart o S em E 03 3 Tarse i ER a K O0 000000000000 gt sa 000000000000 o0 Sy o So FEP Os cig gall Ch 98mm 110mm oc Ve eo 2 3 Z oc weet eo KE 000 gup SCH TY D o SC anal 953 Figure 27 LPC2148 Education Board Mechanical Dimensions 2 6 JTAG Interface and Reset Control Issue An external JTAG controller can control the reset signal to the LPC2148 Some JTAG controllers will start sending JTAG commands to the internal TAP controller in the LPC2148 immediately after de asserting the reset signal in the JTAG interface Others will wait a short while before start sending commands Note that the behavior can be different for different firmware versions of the JTAG controllers The reset system of the LPC2148 Education Board will keep the reset signal to the LPC2148 asserted for up to 270 ms typically 200 ms after the reset signal is de asserted from the JTAG interface This design will guarantee that short reset pulses will not put the LPC2148 in an undefined state Proper reset pulses will always be generated to the LPC2148 For some JTAG controllers this may however be a problem Some versions of ULINK from Keil are known to have this problem
10. Board Schematics Sheet 1 4 2X32 100MIL INV Q Ka gt E D or H ES 5 w D D A N D l E m F Document Number Connector for ZigBee board Figure 36 ZigBee Expansion Board Schematic Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 43 The ZigBee Expansion Board is based on the well known RF circuit CC2420 from Chipcon Texas Instruments http www chipcon no The LPC2148 communicates with the ZigBee interface via SPI channel 0 The interface is 10 signals in total See the CC2420 datasheet for details about the interface The CC2420 and all RF parts of the design are placed on a separate board 2 4GHz RF card AC163027 2 from Microchip The schematic above only illustrates the signals to the connector to the RF board Detailed schematic for the RF board is delivered when purchasing the ZigBee Expansion Board The circuit is powered with 3 3V from the LPC2148 Education Base Board Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 44 12 App G Prototype Expansion Board This chapter contains detailed information about the electrical design of the board 12 1 Board Schematics Sheet 1 1 TITLE Prototype Expansion v1 8 Document Number H H i H z E H H amp Figure 37 Prototype Expansion Board Schematic Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 45
11. a time in a circular pattern The update frequency must be higher than 100 Hz in order not to see flickering on the LEDs The LPC2148 microcontroller has two on chip SPI serial communication channels The shift registers are accessed via the SPI bus channel 0 and signal P0 15 is used as device select pin SPI mode 0 can be used to shift data into the shift registers SPI channel 0 is also shared with the MMC SD interface 8x8 LED Matrix with SPI Interface Q7 Q8 Q9 BC857B BC857B BC857B SPI_MOSI SPI_SCK SPI_SEL_LEDS SPI_MISO 3V3 KE G vec 3 Os S Si 3 8 a O D Figure 21 LPC2148 Education Board Schematic page 3 8x8 LED Matrix with SPI Interface The 8x8 LED matrix circuit can be disconnected from SPI channel 0 by removing jumpers J24 J33 J37 and J42 Normally jumper J42 should not be inserted since the output from U6 is not three states when the shift registers are not enabled by device select signal P0 15 If inserted the output from U6 will collide with the data output DOUT from the MMC SD interface The only reason to have jumper J4 inserted would be to read back the last two bytes shifted into the shift registers and there is no typical reason to do this 2 1 19 Page 3 Brushless DC Motor Control The final part of the LPC2148 Education Board is the Brushless DC motor control The control chip MPC17511 from Freescale is used See the datasheet for details about the control
12. connectblue com Two different Bluetooth module series can be used OEMSPA1x 3x or OEMSPA3 1x 33x The Bluetooth Expansion Board is delivered with either OEMSPA13i or OEMSPA31 11 They are compatible in most aspects The LPC2148 Education Board communicates with the Bluetooth module via UART 1 Some of the modem signals can be used but are not required The serial interface to the modules is programmable The default is to use RTS CTS flow control but this can be disabled by software It is possible to communicate directly with the Bluetooth module via the on board RS232 interface Communication can take place via a simple terminal program or via an external application program The default communication setting is 57 6 kbps 8N1 RTS CTS flow control Note that the Bluetooth module will get default values i e factory reset values by pressing the switch during power up of the module When placing the four jumpers to the DSUB side the module s serial channel is connected to the on board RS232 serial interface i e the DSUB When the jumpers are to the module s side the serial channel is connected to the LPC2148 s UART 1 See picture below for details Jumpers Upper position as picture show connects the Bluetooth module s serial channel to the DSUB Lower position connects it to UART 1 of LPC2148 esu eu H eno elen Nk lem Jean 0000 Jeau e joys Ae YTT LG Jam
13. frequency will be heard The alternative PWM feature of pin P0 7 the PWM2 signal can be used to modulate the buzzer to oscillate around different frequencies It s not the pulse width feature that is used to change the frequency Only the volume of the sound will be changed by alternating the pulse width Instead it s possible to change the frequency of the PWM signal and this will also change the frequency of with the buzzer oscillate The buzzer can be disconnected by removing jumper J16 and this is also the default position for this jumper since the buzzer sound can be quite annoying if always left on Buzzer S Ed Q6 BC857B SG1 F TMB Figure 14 LPC2148 Education Board Schematic page 2 Buzzer Note that signal P0 7 is shared with several other parts of the design for example the motor control the red LED in the RGB LED servo motor interface analog output and the individual LEDs see Figure 10 Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 19 2 1 12 Page 2 Servo Motor Interface Figure 15 below illustrates the servo motor interface part of the design As seen the interface is as simple as it gets Only a three position connector that is standard for servo motors The servo is powered from the 5V power supply Also this part of the design uses the PWM2 signal available on pin P0 7 The servo position is controlled by altering the pulse width of the PWM sig
14. stal PO 13 DTR1 MAT1 1 AIN12 ES 5 y PO 14 DCD1 EINT1 SDA1 42014 C7 C8 PO 15 RIV EINT2 AIN13 33pF 33pF mar PO 16 EINTO MATO 2 CAP0 2 8 P0 16 GND D PO 17 CAP14 2ISCK1MAT12 320 17 PO 18 CAP1 3IMISOUMAT1 3 2 P0 18 P0 19 MAT1 2 MOSIT CAP1 2 VBAT Power PO 20 MAT1 3 SSELVEINT3 seen PO 21 PWM5 AIN14 CAP1 3 iE P0 22 AIN15 CAPO O MATO 0 Q 2 po 23 98 Pa S CH BAT_IN D1 D2 PO 25 AIN4 AOUT L PO FE ale PO 26 AINS J 4020 26 BAWs6 bAwse PO 27 AINO CAPO 1 MATO 1 kl PO 28 AINT CAPO 2 MATO 2 LE ales eg PO 29 AINZ CAPO 3IMATO 3 LEE d PO SO AINSIEINT3ICAPO 0 48 PO 22uF 6V 100nF ee Ca LU SE P1 16 TRACEPKTO LA 10uH D D gem P1 17 TRACEPKT1 5 P1 18 TRACEPKT2 E P1A9 TRACEPKT3 jt PHS P1 20 TRACESYNC L P121 PIPESTATO kB P122 PIPESTAT E P1 23 PIPESTAT2 REF A P1 24 TRACECLK 2E A P1 25 EXTINO 28 _P 1 25 __ P1 26 RTCK Lil GP L2 p1 27T00 L EP 1 27 100 TOuH zap L EL Catch L pang k L P1 31 TRST IRST i VREF Voltage D Figure 4 LPC2148 Education Board Schematic page 1 CPU The microcontroller crystal frequency is 12 0000 MHz This frequency has been selected in order to allow maximum execution speed 5 x 12 MHz 60 MHz which is the maximum frequency The on chip UART peripheral includes a fractional baud rate generator that allow standard baud rates to be generated from the 60 MHz base clock The USB clock is also generated from the 60 MHz clock without any problems There is also a 3
15. 2 768 kHz crystal clock for the on chip real time clock peripheral unit or RTC for short The microcontroller can be placed in a very low power mode while the RTC operates and keeps track of time Power for the RTC during these low power modes comes from the VBAT input pin Power is sourced either from the 3 3V power supply or the external VBAT_IN signal available on the expansion connector depending on which one have highest voltage The LPC2148 also contains an Analog to Digital Converter or ADC for short as well as a Digital to Analog Converter DAC These two peripheral units need a reference voltage which is supplied from the VREF input pin Jumper J6 selects two different sources for VREF The CPU power supply 3 3V is used and divided by 3 2 The power supply is low pass filtered for noise immunity The precision of the power supply is 1 Alternatively an external precision voltage is used the VREF_ IN pin on the expansion connector Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 12 2 1 2 Page 1 Power Supply The power supply uses a conventional low dropout voltage regulator the Sipex SP1117 The LPC2148 need only a single 3 3V voltage and has an internal 1 8V regulator for powering the core Some other processors in the LPC2xxx series require both a 3 3V anda 1 8V voltage For a full specification of the SP1117 voltage regulator see the datasheet from Sipex also included on the CD R
16. 48 Education Board contains the following e The LPC2148 Education Board e A modem serial cable DB9 male to DB9 female DB9M DMO9F for connecting the LPC2148 Education Board to a PC e A USB cable of type B to A for powering the boards from a PC e CD ROM with additional material and programs including complete and evaluation versions of different development environments An optional JTAG interface can be used for debugging during program development The interface is not strictly needed but can be needed for more advanced debugging 1 2 Features Embedded Artists LPC2148 Education Board with Philips ARM7TDMI LPC2148 microcontroller lets you get up and running quickly The small form factor board offers many unique features that ease your learning curve and program development e Philips ARM7TDMI LPC2148 microcontroller with 512 KByte program Flash and 32 8 KByte SRAM e 12 0000 MHz crystal for maximum execution speed and standard serial bit rates Phase locked loop PLL multiplies frequency with five 5 x 12 MHz 60 MHz e 32 768kHz RTC crystal e Onboard Peripherals 2x16 character LCD with background light Joystick switch RS232 interface on UART 0 USB 2 0 device interface RGB LED each color can be controlled via PWM signal 8 LEDs Pushbutton on P0 14 interrupt input 8x8 LED matrix controlled via shift registers in the SPI bus MMC SD memory card interface Brushless DC motor co
17. Ask Keil for available firmware updates If you experience problem you might lift pin 2 of U3 the combined reset controller and E PROM This will reconnect the reset controller from the reset signal See Figure 2 on page 9 for details about the reset controller This solution is possible if it is acceptable to control the reset signal from the JTAG controller Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 29 3 Getting Started 3 1 Test program The LPC2148 Education Board comes preloaded with a test program This program can be used to verify that the board operates correctly e Download the test program by using the hex file for the test program e Insert all jumpers except J42 e Push the reset button e Watch the running one on the individual LEDs except for P0 10 After a few rounds LED P0 10 will flash alone e Also watch the printed information on the terminal se below e After that a test loop is entered o Printed message on the LCD and flashing of backlight o Scrolled message on 8x8 LED matrix o PC mouse emulation over USB and joystick switch o Dimming of RGB LEDs o Running the motor forward and backward A terminal program should be attached to the RS232 DSUB 9 connector The test program will output test information regarding the DC and E PROM test MMC SD test as well as the RTC crystal test Also the UART RS232 channel can be tested by typing characters in the terminal prog
18. OM Figure 5 below illustrates the voltage regulator part of the design As seen power can come from either an external power adapter via a standard 2 1 mm power connector or from the USB connector Diode D4 keeps the USB interface from being reverse fed Normally power is taken from the USB connector but in some cases the 2 1 mm connector can be used for example when the power need for expansion boards is high and the USB cannot supply the needed current 2500mA A transient suppression diode D5 protects the board from power surges via the power input ME c19 c20 c21 c22 c23 C24 c25 ee lee ee d eg dE d ee d Ohn GND Ou Ou n Op On Om D 1 Chip Power LED oO oO S S CH oO 2_1MMJACK PAD1 z Vi io PAD2 Ga 6 8v Je 5 Q D 5 PAD3 SA D D Power Input Figure 5 LPC2148 Education Board Schematic page 1 Power Supply There are three pads to ease measurements of the incoming 5V voltage and the generated 3 3V voltage see PADI PAD3 When ON a small green LED indicates the presence of 3 3V voltage See Figure 26 on page 27 for a description where the pads and the green LED are placed on the PCB 2 1 3 Page 1 RS232 and ISP UART O0 on the LPC2148 is connected to a RS232 interface via a Sipex SP3232E standard RS232 interface chip It s a3 3V powered chip with integrated ESD protection in order to minimize the risk of damaging the interface The RS232 interface is not a full interface onl
19. SM RF Ethernet CAN RS485 and Fieldbuses 1 4 2 LPC2xxx QuickStart Boards and Kits Visit Embedded Artists home page www EmbeddedArtists com for information about other QuickStart boards kits or contact your local distributor Copyright 2006 Embedded Artists AB ao 3 KA Hd Ki KI N Kai oS Le D i oO 5 D lu Ka ka N iS a l 2 Board Design This chapter contains detailed information about the electrical and mechanical design of the LPC2148 Education Board 2 1 Board Schematics EZE aas SOEUSIUt OVE Ke Jo12euu0c uoisuedxg 200 am Amanz Tagung zzo iw ASHLNE Id Esser td MMS BdIdeZ id OLVISIdidIZ id ONASIOVHLOZ bd ELNIIOVULIBE Id TLE VULEL 14 LLM VULL E ld LAAT VULOL 14 i DRECHEN Od O OLVWO DEWOSINIVICE Ot E LEIT Od EIN VISSA Lengt Od D CH DECH DEEN DECKER 1mdut Jemod CEO KA WON Lagu zer Su a JoyeinBey LYN AC e Sfeon JIYA A0 2 H l JL NI ER ONO WOOL ANAN IBS Ndo a E 34001 19 w n anota miy anoiy inoz Ng soeya u JSN Figure 1 LPC2148 Education Board Schematic page 1 Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide z Oeauig Fe zaquny yUaUND0g WOUdZ3 OZI pue UoHesaUED jean LINO JONDSS600 iair T rt a ep u GS OWW JOPSUUD SOELa UI JOJON OMAS Jezzng a31 89H Figure 2 LPC2148 Education Board Sch
20. adjusting the pulse width of the signals The list below explains the signal connections e Red LED controlled by signal P0 7 PWM2 e Blue LED controlled by signal P0 8 PWM4 e Green LED controlled by signal P0 9 PWM6 The PWM signals are available as alternative signals on the pins and are generated from the PWM peripheral unit Figure 13 below illustrates the RGB LED part of the design Note that the LEDs are driven from the 5V power supply This is because the forward voltage drop of the blue LED is typically around 3 5V which is more than the 3 3V power supply for the LCP2148 The RGB LED can be disconnected by removing jumpers J34 J35 and J36 Also note that the signals P0 8 P0 10 are used for other parts of the design also for example for controlling the buzzer the motor control analog output the servo motor interface P0 7 as well as for the individual LEDs see Figure 10 Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 18 RGB LED 1 2k N ei bel be bel D a a 1k 470 Q16 BC847C Q17 Q15 BC847C BC847C R34 R35 R36 Figure 13 LPC2148 Education Board Schematic page 2 RGB LED 2 1 11 Page 2 Buzzer There is also a small piezoelectric buzzer on the LPC2148 Education Board Figure 14 below illustrate the buzzer part of the design By pulling pin P0 7 low current will flow through the buzzer and a relatively sharp single tone
21. be applied over the motor before it starts rotating This level is about 35 40 duty cycle When the motor rotates it can keep rotating at slightly lower speed than the start rotating speed Motor Speed Full Speed Duty Cycle 100 Figure 23 Brushless DC Motor Operation Area Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 25 2 2 Jumpers The LPC2148 Education Board is full of jumpers in order to be able to connect disconnect all different parts of the external circuits Figure 24 below illustrates all jumpers and explains to what part of the design they belong Automatic ISP In order from left to right J5 P0 14 TC EPROM In order from left to right J11 SDA P0 3 J10 SCL P0 2 Enable JTAG J9 USB Powering UART 0 In order from left to right J3 Receive P0 1 J4 Transmit P0 0 Left pos from 3 3V Right pos VREF IN RGB LED In order from left to right J34 red P0 7 J36 green P0 9 J35 blue P0 8 MMC SD Interface In order from top to bottom J21 MISO P0 5 J20 SCK P0 4 J17 MOSI P0 6 J14 Select P0 11 Board v1 8 2x16 Character LCD In order from left to right J38 RS P1 24 J39 R W P0 22 J40 E P1 25 J25 DO P1 16 J26 D1 P1 17 J27 D2 P1 18 J28 D3 P1 19 J29 D4 P1 20 J30 D5 P1 21
22. ded Artists AB Feedback We appreciate any feedback you may have for improvements on this document Please send your comments to support EmbeddedArtists com Trademarks InfraBed and ESIC are trademarks of Embedded Artists AB All other brand and product names mentioned herein are trademarks services marks registered trademarks or registered service marks of their respective owners and should be treated as such Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 3 Table of Contents 1 Introduction 5 1 1 Contents 5 1 2 Features 5 1 3 Expansion Boards 6 1 4 Other Products from Embedded Artists 7 1 4 1 Design and Production Services 7 1 4 2 LPC2xxx QuickStart Boards and Kits 7 2 Board Design 8 2 1 Board Schematics 8 2 1 1 Page 1 CPU 11 2 1 2 Page 1 Power Supply 12 2 1 3 Page 1 RS232 and ISP 12 2 1 4 Page 1 USB 13 2 1 5 Page 1 JTAG 14 2 1 6 Page 1 Expansion Connector 14 2 1 7 Page 2 LEDs 15 2 1 8 Page 2 Push button 16 2 1 9 Page 2 Joystick switch 16 2 1 10 Page 2 RGB LED 17 2 1 11 Page 2 Buzzer 18 2 1 12 Page 2 Servo Motor Interface 19 2 1 13 Page 2 MMC SD Interface 19 2 1 14 Page 2 Reset Generation and DC E2PROM 20 2 1 15 Page 3 Analog Inputs 20 2 1 16 Page 3 Analog Outputs 21 2 1 17 Page 3 2x16 Character LCD 21 2 1 18 Page 3 8x8 LED Matrix with SPI Interface 22 2 1 19 Page 3 Brushless DC Motor Control 23 2 2 Jumpers 25 2 2 1 Illegal Jumper Combinations 25 2 3 Connectors
23. dress bit CD 1 read signal RD 1 write signal WE and 1 chip enable signal CE It s also possible to control the backlight via signal P0 30 All pins can be disconnected from the LPC2148 pins if needed by removing the jumpers The pins used for this interface are the same as for creating the bus interface to the 16x2 character LCD on the LPC2148 Education Board Therefore it is important to note that all jumpers for the LCD interface on the LPC2148 Education Board must be removed before the LCD Expansion Board is connected See picture below LCD Jumpers Remove all GE LGL o Gr Too Bret fo os os oe os Bier on jooooss C 2005 Embedded Artists uwuu EmbeddedArtists com ni P9 20 AIN2 P8 23 EP LE Figure 33 LCD Jumpers on LPC2148 Education Board It s possible to adjust the display contrast with a small trim potentiometer on the LCD Expansion Board The LCD is powered from the 5V power supply 5V power is no problem since all pins on the LPC2148 are 5V tolerant and a high logic level from the CPU powered by 3 3V is also interpreted as a high logic level by the LCD Display contrast is adjusted via trim potentiometer R53 There are two different connectors for the display on the LCD Expansion Board One has 21 pins and the other has 22 pins This is just for allowing more options when selecting the LCD The currently used display is the 240 x 128 pixel monochrome grap
24. ductors philips com acrobat usermanuals UM10139_1 pdf 3 Philips LPC2148 Errata Sheet http www semiconductors philips com acrobat erratasheets 2 1 AN pdf 4 ARM7TDMI Technical Reference Manual Document identity DDI0029G http www arm com pdfs DDI0029G_7TDMI_ R3_trm pdf 5 ARM Architecture Reference Manual Document identity DDIO100E Book Second Edition edited by David Seal Addison Wesley ISBN 0 201 73719 1 Also available in PDF form on the ARM Technical Publications CD 6 ARM System Developer s Guide Designing and Optimizing System Software by A N Sloss D Symes C Wright Elsevier ISBN 1 55860 874 5 7 Embedded System Design on a Shoestring by Lewin Edwards Newnes ISBN 0750676094 8 GNU Manuals http www gnu org manual 9 GNU ARM tool chain for Cygwin http www gnuarm com 10 An Introduction to the GNU Compiler and Linker by Bill Gatliff http www billgatliff com 11 LPC2000 Yahoo Group A discussion forum dedicated entirely to the Philips LPC2xxx series of microcontrollers http groups yahoo com group Ipc2000 12 The Insider s Guide to the Philips ARM7 Based Microcontrollers by Trevor Martin http www hitex co uk arm lpc2000book index html Especially note document 3 There exist a number of bugs in the processor that is important to be aware of Note that there can be newer versions of the documents than the ones linked to here Always check for the latest information versi
25. ected to VCC of the USB interface Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 14 geg Xo Xo 10nF 500V LED3 390 GREEN Figure 7 LPC2148 Education Board Schematic page 1 USB 2 1 5 Page 1 JTAG The JTAG interface is a standard 20 pin 2x10 connector with shoulders standard at least in the ARM world The JTAG interface shares 6 general IO pins GPIOs and is enabled by shorting jumper J9 i e pulling P1 26 low during reset When the JTAG interface is enabled the 6 IO pins cannot be used for other purposes than the JTAG interface Figure 8 below illustrates the JTAG part of the schematics JTAG Interface Figure 8 LPC2148 Education Board Schematic page 1 JTAG To use the JTAG interface of the LPC2148 Education Board a special JTAG interface pod must be used This pod must be integrated with a debugger in order to do anything useful with it There exist many different manufacturers of JTAG interface pods 2 1 6 Page 1 Expansion Connector The LPC2148 Education Board is not just a monolithic design Via the expansion connector it s possible to expand the design All LPC2148 pins are available on the expansion connector which is a standard 2x32 pin list with 100 mil pin spacing Figure 9 below illustrates the expansion connector part of the design Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 15 Expansio
26. ematic page 2 Copyright 2006 Embedded Artists AB Page 10 LPC2148 Education Board User s Guide Ip 8 9898 10 ve De Au 20 JOUOD JOO OG ssajysnig so37 Ge Ids rE E a 2 gt SAP D 2 gt PL UL EL UE PPLE 8 9898 Ierseng jazseoa jazse9a jazse3a jacseog 8 9898 10 tiie HO 010 80 ei 40 SIBHS U IdS YPM zU G31 8X8 0pogo00000000000 go0000oo0000000o E 5 DSSBRRERLEMERESE o s nduj Boyeuy page 3 Figure 3 LPC2148 Education Board Schematic The following subsections describe in more detail each part of the design Each schematic page is described in turn Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 11 2 1 1 Page 1 CPU The core part of the design is the Philips LPC2148 microcontroller It s an ARM7TDMI S CPU core with a lot of different peripheral units and on chip memory 512 kByte FLASH and 32 8 kByte SRAM There is no external memory bus interface Figure 4 below illustrates the CPU section of the design U2 LPC2148 el po ormxoopwm LEO o o PS CS 2 SCLO CAPO ap 12 0000MEZ PO S SDAOIMATO OEINT LZ PO 4 SCKOICAPO 1 AING k CPU Crystal PO 5MISOO MATO 1 AIN7 L ry c3 PO 6MOSIO CAPO 2 Ain8 3 EUR 33pF PO 7 SSELO PWMZ EINT2 PO 8 TXD1 PWMA AING 23 EZ PO 9 RXD1 PWM6 EINT3 k EU GND Q2 5 PO 10 RTS1 CAP1 0 AIN10 32_B0 10 32 768kHz PO 11 CTS1 CAP1 1 SCL1 k EU lIl P0 12 DSR1 MAT1 0 AiN11 L RTC Cr
27. he interface circuits are powered with 3 3V from the LPC2148 Education Board Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 40 10 App E MP3 Decoder Expansion Board This chapter contains detailed information about the electrical design of the board 10 1 Board Schematics Microphone input TITLE MP3 Expansion v1 8 Date 2006 02 23 11 48 35 Document Number wei y t EI oe uo Li g KI Pog SPI_MISO SPL_MOSI Figure 35 MP3 Decoder Expansion Board Schematic Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 41 The MP3 Decoder Expansion Board is based on the well known MP3 decoder chip vs1002 from VLSI http www vlsi fi The LPC2148 communicates with the vs1002 decoder chip module via SPI channel 0 Four other signals other than the three SPI signals are needed for the interface See the vs1002 datasheet for details about the interface The audio is available via a 3 5mm headphone connector No external amplifier is needed for small headphones A microphone input is also available note that microphone is not included for recording audio The circuit is powered with 3 3V from the LPC2148 Education Base Board Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 42 11 App F ZigBee Expansion Board This chapter contains detailed information about the electrical design of the board 11 1
28. hical LCD SMG210128A from Sunman Copyright 2006 Embedded Artists AB Page 38 LPC2148 Education Board User s Guide 9 App D UART amp RS485 Expansion Board This chapter contains detailed information about the electrical design of the board 9 1 Board Schematics T T 2884S TA uotsuedx3 Lyn JILL a j 9 ai Figure 34 UART amp RS485 Expansion Board Schematic Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 39 The UART amp RS485 Expansion Board contains the SP3243E full modem RS232 interface and the SP3491E RS422 485 interface from Sipex Both interfaces include on chip ESD protection The LPC2148 communicates with the UART amp RS485 Expansion Board via UART channel 1 Note that both interfaces cannot be used at the same time since UART 1 is used by both interfaces All signals in UART 1 Ge P0 8 P0 15 can be disconnected by removing jumpers The RS232 interface contains control for all signals The DSUB is a male connector The RS485 interface can actually be used as either a RS422 or RS485 interface If jumpers J7A B are inserted the Rx and Tx lines are connected and the interface is a RS485 interface De a half duplex two write interface If the jumpers are removed the Rx and Tx signals are separated i e a full duplex 4 wire interface With jumper J8 it is possible to add a 120 ohm termination resistor which some applications need T
29. ht even be useful to have LED indicators for some signals 2 3 Connectors Figure 25 below illustrate the position of all external connectors on the LPC2148 Education Board RS232 9 pos DSUB Input power Zi a a g a E G Q oo Se e ja OB D o Bio aan epes LJ CH EA isda ES F D DD o 00 000 Ge OO PB Gem Pa oe DO 00 Le RESET ep a OO GI o og CEID Bo wiki ei S 000000000000 000000000000 D SES EI ji Beet KiC LPC2138 48 Education Board v1 0 C 2005 Embedded Artists wuw Embeddedfrtists com O NDAOUT HIN Q P9 14 AINA P 28 az P8 29 SSSSSSS Expansion connector J2 Servo Motor J55 Figure 25 LPC2148 Education Board External Connectors Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 27 2 4 Important Components Figure 26 below illustrates the position on the board for some important components in the design USB connect Reset push button Le af BG EL Taeser D 00 oo KI C 2005 Embedded Artists wuw Embeddedfrtists com Ves E a H H g ER oo REE reest SIS B GITT Ges oats CAO 00000000 l n Mannan EE OO 8S5948a0 UT waar Oe P 14 DIN 8 287 AIN2 P8 29 Voltage measurements contrast pads for analog output Figure 26 LPC2148 Education Board Important Components Copyright 2006 Embedded
30. ion Board Schematic page 2 MMC SD Interface Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 20 Note that the switches for card detect and write protect are not connected at all in this design 2 1 14 Page 2 Reset Generation and DC E2ZPROM The rest generation is handled by a mixed signal chip CAT1025 from Catalyst Semiconductor The reset signal will be held active i e low until the supply voltages 3 3V is within margins The reset duration is typically 200 mS consult the CAT1025 datasheet for exact details also included on the CD ROM The output reset signal is an open collector open drain output An external reset source can also control the reset generator Figure 17 below illustrates this part of the design There is also a reset push button SW 1 and both the signals RES IN and RES OUT are available on the expansion connector Note that an external driver of these signals should be an open collector open drain driver There is also a red LED that lights when the reset signal is active Reset Generation and I2C E2PROM ise gt ise VCC RESET MR RESET_INV Ll o Leu Su PUSHBUTTON GND D Reset LED v gt mM eo D LED2 470 RED w Figure 17 LPC2148 Education Board Schematic page 2 Reset Generation and 12C E2PROM The CAT1025 chip also contains a 2kbit E7PROM accessible via the DC interface The LPC2148 microcontr
31. ke and debugger e The program Programmers Notepad which is a very good program development editor and project manager e The Eclipse development environment including the CDT C C Development Tools project 4 2 Product Registration By registering as a customer of Embedded Artists you will get access to more valuable material that will get you up and running instantly e Access to a Real Time Operating System RTOS in the form of a library that can be used for non commercial applications e Access to anumber of sample applications that demonstrated different peripheral functions in the LPC2148 processor e Access to the latest versions of all information and programs on the CD ROM Registering is easy and done quickly 1 Go to http www EmbeddedArtists com select Support and then Register 2 Type in the products serial number can be found on the LPC2148 Education Board or on the package carrying the board along with your personal information Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 31 5 Further Information The LPC2148 microcontroller is a complex circuit and there exist a number of other documents with a lot more information The following documents are recommended as a complement to this document 1 Philips LPC2148 Datasheet http www semiconductors philips com acrobat datasheets LPC2141 42 44 46 48 1 pdf 2 Philips LPC2148 User s Manual http www semicon
32. ler included on the CD ROM The interface principles are really easy An enable signal exists and is controlled by signal P0 10 The motor controller is enabled when P0 10 is high Two other input signals control the speed and direction of the motor rotation These signals are PWM signals and the duty cycle controls the speed of the motor Signal P0 8 is used to rotate to motor in one direction and P0 9 is used for the other direction When a signal is not used it should be help low Figure 22 below illustrates the brushless DC motor control part of the design Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 24 3V3 Brushless DC Motor Control VCC LOGIC VCC POWER C1H T ki Chip D EN GIN ouT2 mi IN2 MOT_EN GND POWER GND LOGIC MOT_PWM MOT_PWM Figure 22 LPC2148 Education Board Schematic page 3 Brushless DC Motor Control Note that the motor controller can draw a lot of power from the 5V power supply This will happen if the signals P0 8 P0 9 are high at the same time as signal P0 10 This unfortunately happens when the processor is in reset state Therefore jumper J49 should normally not be inserted unless the motor controller is used The motor has a limited operation area when it comes to rotation speed The diagram below in Figure 23 illustrates the area The motor does not rotate all the way from zero speed up to full speed A certain DC level must
33. n Connector 2X32 100MIL Figure 9 LPC2148 Education Board Schematic page 1 Expansion Connector The power voltages 5V and 3 3V are available on the expansion connector Note that the current consumption of external circuitry on the expansion boards must be low The on board 3 3V voltage regulator can only supply up to 300 mA to external circuits Note also that the 5V power supply must be able to deliver all needed current In the case that the USB port is used to power the board the total current consumption must be less than 500 mA Else the USB host in the other end will shut down current delivery completely 2 1 7 Page 2 LEDs The port pins of the LPC2148 microcontrollers have a 4 mA driving capacity just enough to directly drive LEDs Figure 10 below illustrates the 8 LEDs in the design The LEDs are connected to pin P0 8 P0 15 and are red The 470 ohm resistors limit the current to about 4 mA A low output pin drives current through the LEDs and they will light Each LED can be individually enabled or disabled via jumpers e J43 P0 8 e J44 P0 9 e J46 P0 10 e J47 P0 11 e J48 P0 12 e J50 P0 13 e J52 P0 14 e J54 P0 15 Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 16 Figure 10 LPC2148 Education Board Schematic page 2 LEDs 2 1 8 Page 2 Push button The signal P0 14 can be configured as an interrupt input pin on the processor A push bu
34. nal Servo Motor Interface Connector 1 2 GND Figure 15 LPC2148 Education Board Schematic page 2 Servo Motor Interface Note that signal P0 7 is shared with several other parts of the design for example the motor control the buzzer analog output the red LED in the RGB LED and the individual LEDs see Figure 10 2 1 13 Page 2 MMC SD Interface The SPI bus of the LPC2148 can be used to interface a MMC SD memory card when operating in the simpler MMC mode Pin signal P0 11 is used as device select Philips has published an application note describing how to implement the low level interface reading and writing sectors on the memory card See ANI0406 Accessing SD MMC card using SPI on LPC2000 for details Figure 16 below illustrates the MMC SD interface part of the design The interface can be disconnected from the LCP2148 by removing jumpers J14 J17 J20 and J21 Also note that jumper J42 on the SPI interface for the 8x8 LED matrix should not be installed since this output is not a three state output and will hence collide with the MISO signal DOUT on the MMC SD interface There is also no typical need to have jumper J42 installed so this is normally not a problem MMC SD Interface J19 SPI_SEL_MMC MMC SD SDDMF 0095B KINGFONT cs DIN GND 1 Ed SPI_MOSI 6 VEG S E CLK GND 2 C29 nal 100nF SPI_SCK 4 RSV2 CARD DETECT D COMMON WRITE PROTECT GND 3 SPI_MISO GND4 Figure 16 LPC2148 Educat
35. ntrol Piezoelectric buzzer Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 6 Servo interface 3 pole 2 Analog inputs Low pass filtering of PWM signal Analog output Reset button e Connectors R S232 female DSUB 9 ESD protected USB type B connector MMC SD memory card connector Servo 3 pin connector JTAG 64 pin expansion connector all LPC2148 I O pins are available on connector 2 1 mm power supply connector e 2 Kbit PC E PROM for storing non volatile parameters e Onboard low dropout voltage and reset generation Generates 3 3V from a 5V supply 3 3V available for external circuits up to 300 mA e Power supply 4 5 6 VDC 2150 mA either from USB connector or 2 1 mm power connector e Simple and automatic program download ISP via RS232 channel Circuit that automatically controls the bootloader from RS232 channel e Dimensions 139 x 110 mm Four layer PCB FR 4 material for best noise immunity 1 3 Expansion Boards The 64 pin expansion connector with all LPC2148 I O pins available allows the LPC2148 Education Board to be expanded with new and exciting hardware The experiments can be more advanced and complex by using the expansion boards The list below presents the first set of available expansion boards As seen many of the boards are communication oriented e Ethernet board 10Mbps with SPI interface e Bl
36. oller has two on chip DC communication channels Channel 0 is used for communicating with the E PROM The other channel can optionally be used on an expansion board More peripheral units are easily connected to the two wire UC bus just as long as the addresses do not collide The address of the 2kbit E7PROM is 0xA0 The UC interface to the CAT1025 can be disconnected from the LPC2148 by removing jumpers J10 and J11 Note that the pull up resistors which are always needed on I C busses are included on the board These pull up resistors are 3000 ohm each If using the second DC channel do not forget to connect pull up resistors to these signals also Note that this must be done even if the DC functionality is not used enabled Pins P0 11 and P0 14 are open drain I Os and must have pull up resistors when configured as outputs This is unfortunately easy to forget but they are included on the LPC2148 Education Board 2 1 15 Page 3 Analog Inputs The LPC2148 has 14 analog inputs connected to two different 10 bit ADC Analog to Digital Converter The conversion time is as short as 2 44 us and the input pins VREF and Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 21 VSSA are used as conversion reference Figure 19 below illustrates the analog input part of the design As seen two trim potentiometers are used to generate a variable voltage to analog input 1 P0 28 and 2 P0 29 Note that the analog inp
37. on Datasheets for all circuits on the LPC2148 Education Board are included on the accompanying CD ROM Copyright 2006 Embedded Artists AB Page 32 LPC2148 Education Board User s Guide 6 App A 10M Ethernet Expansion Board This chapter contains detailed information about the electrical design of the board 6 1 Board Schematics T T 8884S S IS EZ Z0 9007 Oe WS zaquny u wn20g TA uorsuedxg au4ay J WAT GUILL Figure 28 10M Ethernet Expansion Board Schematic Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 33 The design is centered on the ENC28J60 Ethernet controller from Microchip It s a very nice chip with SPI interface Only 6 signals are needed 4 for SPI channel reset and interrupt The datasheet of the chip explain all details Especially note the errata sheet that indicates a minimum SPI clock frequency of 8 MHz This is not possible to achieve with SPI channel 0 but luckily it is with the SSP channel also commonly referred to as SPI channel 1 If SPI channel 0 is used it is alternatively possible to create a software workaround for the problem simple read the PHY registers after a write operation rewrite the value if not correct It is possible to select with jumpers which SPI channel to connect the ENC28J60 to see picture below Jumpers Upper position as picture show connects the Ethernet controller to SPI Dn channel 0
38. processor samples P0 14 low after reset the bootloader is entered else the application code is executed The automatic ISP functionality can be disabled by removing jumpers J5 and J7 Note that some terminal programs notably Windows Hyperterminal control the RTS DTR signals in an unfavorable way so that the board always enters bootloader mode or is always in reset more In these cases the jumpers must be removed or a serial cable with only receive and transmit signals must be used Figure 6 below illustrates the RS232 and ISP part of the design E RS232 for UART 0 and ISP gt U1GS1 J1 a C2 C1 S D Tage de Sich ot Le c4 c5 CS Cee dE ag C2 100nF GND AND TIIN OUT T2IN T2OUT RIOUT BIN R2OUT R2IN SP3232E s m Q3 BC847C Q4 BC847C Figure 6 LPC2148 Education Board Schematic page 1 RS232 and ISP 2 1 4 Page 1 USB The LPC2148 also contains a USB 2 0 device interface as one of its peripheral units Figure 7 below illustrate the USB part of the design Low pass filtering is added for noise immunity The USB interface supports the Soft Connect functionality and voltage sense see LPC2148 User s Manual for more information about these functions The Soft Connect feature is controlled by IO pin P0 31 and is activated by placing a 1 5 kohm resistor between the D signal and 3 3V A green LED also is ON when the resistor is resent The voltage sense feature is handled by IO pin P0 23 which is conn
39. ram The settings for the terminal program are 38 4 kbps 8 data bits no parity bits and one stop bit i e 8N1 3 2 Program Development Consult the QuickStart Program Development User s Manual for more information about the QuickStart Build Environment from Embedded Artists and program development for the ARM7 in general Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 30 4 CD ROM and Product Registration The accompanying CD ROM contains a lot of information and programs that will easy your program development Note that there may be newer versions of different documents and programs available than the ones on the CD ROM See Section 4 2 for information about the product registration process which allows you to always have access to the latest versions 4 1 CD ROM The following is included on the CD ROM e The preloaded test program as a HEX file e The two different ISP download programs e Datasheets of all circuits on the LPC2148 Education Board e QuickStart Build Environment from Embedded Artists which contains a complete setup of a build environment for GCC e A complete development environment Rowley Associates CrossWorks for ARM 30 day evaluation version e A complete development environment IAR Embedded Workbench for ARM Kickstart Edition with 32 Kbyte program size limit e Another complete development environment GCC GNUARM distribution including compiler linker ma
40. tton is connected to this signal so it s possible to pull the signal low There is a pull up resistor 24 kohm on the signal which is also needed for the ISP feature The signal P0 14 must be sampled high after reset in order to start normal program execution else the internal bootloader will be activated Figure 11 below illustrates the push button part of the design Push button sw2 TM PUSHBUTTONSMD pi GND GND Figure 11 LPC2148 Education Board Schematic page 2 Push button 2 1 9 Page 2 Joystick switch There is a joystick switch on the board and Figure 12 below illustrates this part of the design The switch has five internal switches one for the four directions and one center push down switch Note that the five pull up resistors are missing on the main board for version 1 0 Instead these are placed on a small expansion board that is shipped with all version 1 0 LPC2148 Education Boards All of the input pins P0 16 P0 20 can be programmed as interrupt inputs either directly as an EINTx pin or via a CAPture pin which in turn can generate an interrupt Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 17 Joystick Switch Figure 12 LPC2148 Education Board Schematic page 2 Joystick switch 2 1 10 Page 2 RGB LED There is a full color RGB LED that can be controlled by PWM Pulse Width Modulated signals The intensity of each LED can easily be controlled by
41. uetooth board with UART interface e ZigBee board with SPI interface e MP3 decoder board with SPI interface e Graphical monochrome LCD 240x128 pixels with parallel interface e Modem UART 1 and RS485 board e Prototype board More boards are in preparation for example Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 7 e GSM GPRS modem board e GPS board e WLAN IEEE802 11 board and many more to come 1 4 Other Products from Embedded Artists Embedded Artists have a broad range of LPC2xxx based boards that are very low cost and developed for prototyping development as well as for OEM applications Modifications for OEM applications can be done easily even for modest production volumes Contact Embedded Artists for further information about design and production services 1 4 1 Design and Production Services Embedded Artists provide design services for custom designs either completely new or modification to existing boards Specific peripherals and I O can be added easily to different designs for example communication interfaces specific analog or digital I O and power supplies Embedded Artists has a broad and long experience in designing industrial electronics in general and with Philips LPC2xxx microcontroller family in specific Our competence also includes wireless and wired communication for embedded systems For example IEEE802 11b g WLAN Bluetooth ZigBee I
42. uts are counted from analog input 0 but this input is not used in this design The signals P0 28 and P0 29 can be used as general purpose pins if the analog inputs are not used and in this case the analog voltages can easily be removed by removing jumpers J15 and J18 Analog Inputs AIN 2 AIN 1 Figure 18 LPC2148 Education Board Schematic page 3 Analog Inputs 2 1 16 Page 3 Analog Outputs The LPC2148 has one analog output available as an alternative function on pin P0 25 Figure 19 below illustrate the analog output part of the design Via jumper J23 it is possible to connect the analog input to analog input 3 P0 30 There are also special pads to make it easier to measure the analog voltage PAD4 and PAD7 It s also possible to generate an analog output voltage by filtering a PWM signal Also in this case the alternative PWM2 signal on P0 7 is used and low pass filtered It s possible to measure the result with analog input 3 An oscilloscope can with advantage be used to measure the PWM signal before and after the low pass filtering The cut off frequency is 1 2TTRC about 2 Hz which means that any PWM signal with a reasonable high frequency will be adequately low pass filtered It s also possible to measure if the remaining ripple is what can be expected from a simple 1 pole low pass filter like this Analog Outputs PAD6 PWM2 EL LINK e mn CH 180 2 GH P0 30 AIN 3 R29 Ee
43. y the receive and transmit signals are connected to UART O0 There are two UART channels on the LPC2148 and only channel 1 has all control signals needed for a full modem implementation Channel 0 only has receive and transmit signals Channel 1 is free and used by some of the expansion boards Even though the CPU clock crystal is 12 000 MHz any standard baud rate can be generated since both UART channels have a fractional baud rate generator Fractional means that the clock frequency does not have to be divided by an even integer value It can also be divided by a fractional value which means that a lot more baud rates can be achieved from basically any clock crystal frequency There is even an autobauding capability meaning that basically any baud rate can be detected Read more about this functionality in the LPC2148 datasheet The interface can be disconnected by removing jumper J3 and J4 in case an external interface is to be designed for example on a prototype board Copyright 2006 Embedded Artists AB LPC2148 Education Board User s Guide Page 13 Finally there is a special circuit to automate the ISP feature In System Programming With the help of two control signals RTS and DTR the processor can be placed in the bootloader mode The bootloader uses UART 0 for downloading new program images into the processor either into FLASH or into RAM DTR controls the processor reset and RTS can pull signal P0 14 low If the
Download Pdf Manuals
Related Search