PICDEM 2 USER’S GUIDE 2001 Microchip Technology Inc. DS30374D Note the following details of the code protection feature on PICmicro® MCUs. • • • • • • The PICmicro family meets the specifications contained in the Microchip Data Sheet. Microchip believes that its family of PICmicro microcontrollers is one of the most secure products of its kind on the market today, when used in the intended manner and under normal conditions. There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the PICmicro microcontroller in a manner outside the operating specifications contained in the data sheet. The person doing so may be engaged in theft of intellectual property. Microchip is willing to work with the customer who is concerned about the integrity of their code. Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as “unbreakable”. Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our product. If you have any further questions about this matter, please contact the local sales office nearest to you. Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip’s products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. Trademarks The Microchip name and logo, the Microchip logo, PIC, PICmicro, PICMASTER, PICSTART, PRO MATE, KEELOQ, SEEVAL, MPLAB and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. Total Endurance, ICSP, In-Circuit Serial Programming, FilterLab, MXDEV, microID, FlexROM, fuzzyLAB, MPASM, MPLINK, MPLIB, PICC, PICDEM, PICDEM.net, ICEPIC, Migratable Memory, FanSense, ECONOMONITOR, Select Mode, dsPIC and microPort are trademarks of Microchip Technology Incorporated in the U.S.A. Serialized Quick Turn Programming (SQTP) is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. © 2001, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. Microchip received QS-9000 quality system certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona in July 1999. The Company’s quality system processes and procedures are QS-9000 compliant for its PICmicro® 8-bit MCUs, KEELOQ® code hopping devices, Serial EEPROMs and microperipheral products. In addition, Microchip’s quality system for the design and manufacture of development systems is ISO 9001 certified. DS30374D - page ii 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Table of Contents Chapter 1. Introduction 1.1 Welcome ......................................................................................... 1 1.2 PICDEM 2 Demonstration Board .................................................... 2 1.3 Sample Devices .............................................................................. 3 1.4 Sample Programs ........................................................................... 3 1.5 PICDEM 2 User’s Guide ................................................................. 3 1.6 Reference Documents .................................................................... 4 Chapter 2. Getting Started 2.1 PICDEM 2 as a Stand-alone Board – Preprogrammed Device .................................................................. 5 2.2 PICDEM 2 as a Stand-alone Board – Sample Programs 2.3 6 PICDEM 2 Used with an In-Circuit Emulator .................................. 8 Chapter 3. Tutorials 3.1 Main Routine ................................................................................. 10 Chapter 4. A/D Demo 4.1 Main Routine ................................................................................. 12 4.2 InitializeAD Routine ...................................................................... 13 4.3 SetupDelay Routine ...................................................................... 13 4.4 Service_Int Routine ...................................................................... 14 Chapter 5. I2C/EEPROM Demo 5.1 SSP Module .................................................................................. 16 5.2 MSSP Module ............................................................................... 25 Chapter 6. LCD Demo 6.1 4-Bit Interface ............................................................................... 34 6.2 8-Bit Interface ............................................................................... 37 2001 Microchip Technology Inc. DS30374D-page iii PICDEM 2 User’s Guide Chapter 7. USART Demo 7.1 Main Routine .................................................................................42 7.2 IntVector Routine ..........................................................................43 7.3 RcvError Routine ...........................................................................44 Appendix A. Hardware Detail A.1 Processor Sockets ........................................................................45 A.2 Display ..........................................................................................45 A.3 Power Supply ................................................................................45 A.4 RS-232 Serial Port ........................................................................46 A.5 Switches ........................................................................................46 A.6 Oscillator Options ..........................................................................46 A.7 Analog Input ..................................................................................46 A.8 Serial EEPROM ............................................................................47 A.9 Keypad Header .............................................................................47 A.10 LCD Header ..................................................................................47 A.11 Sample Devices ............................................................................47 A.12 Board Layout and Schematics ......................................................48 Worldwide Sales and Service ................................................................. 52 DS30374D-page iv 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Chapter 1. Introduction 1.1 Welcome Thank you for purchasing the PICDEM 2 demonstration board from Microchip Technology Incorporated. The PICDEM 2 is a simple board which demonstrates the capabilities of the 28- and 40-pin PIC16CXXX and PIC18CXXX devices. The PICDEM 2 can be used stand-alone with a programmed part, or with an emulator system, such as MPLAB® ICE. Sample programs are provided to demonstrate the unique features of the supported devices. The PICDEM 2 Kit comes with the following: 1. PICDEM 2 Demonstration Board 2. Sample devices 3. Sample programs (3.5-inch disk) 4. PICDEM 2 Demonstration Board User’s Guide (This document) If you are missing any part of the kit, please contact your nearest Microchip sales office, listed in the back of this publication, for help. 3 4 2 1 Figure 1.1: PICDEM 2 Kit 2001 Microchip Technology Inc. DS30374D-page 1 PICDEM 2 User’s Guide 1.2 PICDEM 2 Demonstration Board The PICDEM 2 demonstration board has the following hardware features: 1. 40- and 28-pin DIP sockets (Although 2 sockets are provided, only one device may be used at a time.) 2. On-board +5V regulator for direct input from 9V, 100mA AC/DC wall adapter or 9V battery, or hooks for a +5V, 100mA regulated DC supply. 3. RS-232C socket and associated hardware for direct connection to RS-232C interface. 4. Unpopulated holes for Access.bus connector and associated hardware. 5. 5K pot for devices with analog inputs. 6. Three push button switches for external stimulus and RESET. 7. Green power-on indicator LED. 8. Eight red LEDs connected to PORTB for displaying 8-bit binary values. 9. Jumper to disconnect LEDs from PORTB. 10. Socket for “canned” crystal oscillator. 11. Unpopulated holes provided for crystal connection. 12. Unpopulated holes provided for Timer1 external crystal. 13. Jumper to disconnect on-board RC oscillator (approximately 2 MHz). 14. 128 x 8 Serial EEPROM. 15. LCD module header. 16. Keyboard header. 17. Prototype area for user hardware. 7 2 8 9 15 1 10 3 17 11 13 4 14 12 2 5 16 6 Figure 1.2: PICDEM 2 Hardware DS30374D-page 2 2001 Microchip Technology Inc. Introduction 1.3 Sample Devices Several UV erasable devices are included. The device types may change, but will generally include a 28-pin and 40-pin device. 1.4 Sample Programs The PICDEM 2 Kit includes a 3.5” disk with sample demonstration programs on them. These programs may be used with the included sample device or with an emulator system. The directory structure of the 3.5-inch disk is: … PIC16CXXX tut.asm a2d.asm iic.asm … PIC18CXXX tut.asm a2d.asm iic.asm 1.5 PICDEM 2 User’s Guide This document describes the PICDEM 2 demonstration board, and tutorial and demonstration software, to give the user a brief overview of the PIC16CXXX series of Microchip microcontrollers, as well as MPLAB IDE. Detailed information on individual microcontrollers may be found in the device’s respective data sheet. Detailed information on the emulation systems may be found in the respective emulator’s user’s guide. Chapter 1: Introduction – This chapter introduces the PICDEM 2 and provides a brief description of the hardware. Chapter 2: Getting Started – This chapter goes through a basic step-by-step process for getting your PICDEM 2 up and running as a stand-alone board or with an emulator. Chapter 3: Tutorial – This chapter provides a detailed description of the tutorial program. Chapter 4: A/D Demo – This chapter provides a detailed description of the demonstration program for the A/D module. Chapter 5: I2C/EEPROM Demo – This chapter provides a detailed description of the demonstration program for the SSP and MSSP modules in I2C mode. The program uses I2C to write to the serial EEPROM. 2001 Microchip Technology Inc. DS30374D-page 3 PICDEM 2 User’s Guide Chapter 6: LCD Demo – This chapter provides a detailed description of the demonstration program for interfacing a keypad to an LCD. A 4-bit and an 8-bit interface program is provided. Chapter 7: USART Demo – This chapter provides a detailed description of the demonstration program for the USART module. Appendix A: Hardware Description: This appendix describes in detail the hardware of the PICDEM 2 board. 1.6 Reference Documents Reference Documents may be obtained by contacting your nearest Microchip sales office (listed in the back of this document) or by downloading via the Microchip website (www.microchip.com). • • • • • • • DS30374D-page 4 Technical Library CD-ROM (DS00161) or individual data sheets MPLAB IDE, Simulator and Editor User’s Guide (DS51025) MPASM™ User’s Guide with MPLINK™ and MPLIB™ (DS33014) MPLAB PRO MATE® User’s Guide (DS30082) PICSTART® Plus User’s Guide (DS51028) MPLAB ICE User’s Guide (DS51159) Microchip Third Party Guide (DS00104) 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Chapter 2. Getting Started The PICDEM 2 may be used as a stand-alone board or with an emulator. For a list of PICmicro® 8-bit microcontroller-compatible emulators, please refer to the Microchip Third Party Guide or the Development Systems Ordering Guide. 2.1 PICDEM 2 as a Stand-alone Board – Preprogrammed Device The PICDEM 2 may be demonstrated immediately by following the steps listed below: • Make sure the pre-programmed sample device is in the appropriate socket on the PICDEM 2 board. • Make sure there are jumpers on J6 (to enable the LEDs) and J7 (to enable the on-board RC oscillator). • Apply power to the PICDEM 2 (Figure 2.1). For information on acceptable power sources, see Appendix A. • Press push-button S2 repeatedly to see the LEDs count up from 00h to FFh. Press push-button S1 to reset. Power Supply (not included) Sample Device PICDEM 2 Demo Board Figure 2.1: PICDEM 2 Stand-Alone 2001 Microchip Technology Inc. DS30374D-page 5 PICDEM 2 User’s Guide 2.2 PICDEM 2 as a Stand-alone Board – Sample Programs To demonstrate PICDEM 2 operation with one of the sample programs, the sample device will have to be erased and reprogrammed. Once the device has been reprogrammed: • Make sure the sample device is in the appropriate socket on the PICDEM 2 board. • Make sure there are jumpers on J6 (to enable the LEDs) and J7 (to enable the on-board RC oscillator). • Apply power to the PICDEM 2 (Figure 2.1). For information on acceptable power sources, see Appendix A. • Consult the appropriate chapter in this document for information on the execution of each demo. 2.2.1. Erasing the Sample Device To erase an EPROM device: • Remove any labels covering the device window. If you do not have a windowed device (Figure 2.2), you cannot reprogram it. A windowed version of all EPROM devices may be ordered by requesting the JW package. • Place the device in an Ultraviolet (UV) EPROM Eraser. The amount of time required to completely erase a UV erasable device depends on: the wavelength of the light, its intensity, distance from UV source, and the process technology of the device (how small are the memory cells). • Verify that the device is blank (i.e., perform a blank check) before attempting to program it. Figure 2.2: PIC16C74 Windowed Device DS30374D-page 6 2001 Microchip Technology Inc. Getting Started 2.2.2. Reprogramming the Sample Device To reprogram the erased sample device, the following will be necessary: 1. Sample programs installed on the hard drive. The PICDEM 2 package includes a 3.5-inch disk which contains sample programs for all the processor types supported. Instructions on how to install the programs can be found in the readme file also on the disk. 2. An assembler, such as MPASM available with MPLAB IDE. Sample programs may be used to program the sample device once they have been assembled. Microchip Technology’s MPLAB Integrated Development Environment includes an assembler (MPASM). However, other assemblers may be used. For a list of PICmicro-compatible assemblers, please refer to the Microchip Third Party Handbook. 3. A device programmer, such as PRO MATE II or PICSTART Plus. Once the sample program is in hex file format, a programmer may be used to program a blank device. Microchip Technology’s PRO MATE II or PICSTART Plus programmers may be used. Both are compatible with MPLAB. However, other programmers may be used. For a list of PICmicrocompatible programmers, please refer to the Microchip Third Party Guide. If the code protection bit(s) have not been programmed, the on-chip program memory can be read out for verification purposes. Note: 2001 Microchip Technology Inc. Microchip does not recommend code protecting windowed devices. DS30374D-page 7 PICDEM 2 User’s Guide 2.3 PICDEM 2 Used with an In-Circuit Emulator To use PICDEM 2 with an in-circuit emulator, refer to the emulator’s user’s guide for instructions on how to connect, power up and configure the emulator to the PICDEM 2. Configure the PICDEM 2 for the desired oscillator as described in Table 2.1. Refer to the emulator’s user’s guide for any oscillator configuration requirements. Table: 2.1 OSCILLATOR SELECTION Oscillator Selection on PICDEM 2 DS30374D-page 8 Modification on PICDEM 2 RC J7 installed, Y2 empty, Y1 empty Crystal J7 removed, Y2 empty, crystal in Y1, caps C2 and C3 installed Canned Crystal J7 removed, oscillator in Y2, Y1, C2, C3 empty Oscillator J7 removed, Y2, Y1 empty 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Chapter 3. Tutorials The tut.asm tutorial program is pre-programmed into the sample device. This program is listed on the included 3.5” program disk for user reference. I.e., if the sample device has been reprogrammed with another sample program, the tutorial may be reassembled and reprogrammed into the device. The tutorial program functions as follows. Pressing the switch S2 causes the LEDs to binary count up to FFh (255 decimal). Past FFh (all LEDs on), the count rolls over to zero (all LEDs off). The program may be reset by pressing the switch S1. For detailed information on the PICDEM 2 hardware, please refer to Appendix A. PORT B LEDs 7 RN2 6 5 4 3 2 1 0 RN1 U2 U1 PIC16C73 (28-pin Device) press to reset press to increase count RESET RA4 S1 S2 PICDEM 2 DEMO BOARD PIC16C64/74 (40-pin Device) ©1994 Figure 3.1: Tutorial 2001 Microchip Technology Inc. DS30374D-page 9 PICDEM 2 User’s Guide 3.1 Main Routine The tutorial program is extremely simple. It begins by configuring PORTB as all outputs to drive the 8 LEDs and initializing a counter. Then it waits in an infinite loop until S2 is pressed. This increases the counter by one, and this number is displayed in binary on the LEDs. Once the count reaches FFh, the next S2 press will roll the count back to 00h. Start Configure PORT B Zero Counter No Switch S2 pressed? Yes Increase Counter Display count on LEDs No Switch S2 released? Yes Figure 3.2: Main Routine DS30374D-page 10 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Chapter 4. A/D Demo The a2d.asm program is a simple implementation of the analog-to-digital (A/D) converter. The program reads A/D channel 0 and displays the results on the LEDs connected to PORTB. If the potentiometer is turned all the way clockwise, all of the LEDs are off. If the potentiometer is turned all the way counter-clockwise, all of the LEDs are turned on. The program is interrupt driven, i.e., the program sits in an infinite loop until the A/D converter interrupts when the conversion is complete and then updates the values on the PORTB LEDs. For more information on A/D module operation, please refer to the PICmicro Mid-range MCUFamily Reference Manual for an operational description and a list of related application notes. For detailed information on the PICDEM 2 hardware, please refer to Appendix A. PORT B LEDs 7 RN2 6 5 4 3 2 1 0 RN1 U2 U1 PIC16C73 (28-pin Device) POTENTIOMETER PIC16C64/74 (40-pin Device) FFh 00h RA0 PICDEM 2 DEMO BOARD ©1994 Figure 4.1: A/D Demo 2001 Microchip Technology Inc. DS30374D-page 11 PICDEM 2 User’s Guide 4.1 Main Routine The main routine of a2d.asm handles the initialization of the PICmicro MCU and then waits in an infinite loop. The first few lines set PORTA as inputs and PORTB as outputs. InitializeAD, the Analog to Digital converter initialization routine, is then called. After the return from InitializeAD, the routine waits for Tad (A/D conversion clock) and then starts an A/D conversion. The program then enters an infinite loop with the reading of the A/D and the updating of the LEDs handled by an interrupt routine Service_Int. Start Configure PORT B Configure PORT A Initialize A/D module (InitializeAD) Wait for Tad (SetupDelay) Start A/D conversion Yes A/D Complete? Service_Int No Figure 4.2: Main Routine DS30374D-page 12 2001 Microchip Technology Inc. A/D Demo 4.2 InitializeAD Routine The InitializeAD routine sets up the A/D converter for use with the PICDEM 2 board. The routine sets RA0, RA1, and RA4 as analog inputs, enables the A/D interrupt, sets the A/D to use the internal RC oscillator, selects channel 0, clears the A/D interrupt flag, enables peripheral interrupts and then enables global interrupts. InitializeAD Set Ch0-Ch3 as analog inputs Select RC clock Select Ch0 as input Turn on A/D Enable Interrupts Return Figure 4.3: Initialize A/D 4.3 SetupDelay Routine This subroutine delays for greater than one A/D converter clock period (2 to 6 µs when using the internal RC clock as this program does) to allow for sampling time. SetupDelay Initialize loop variable Decrement loop variable. Variable=0? No Yes Return Figure 4.4: Setup Delay 2001 Microchip Technology Inc. DS30374D-page 13 PICDEM 2 User’s Guide 4.4 Service_Int Routine This subroutine handles the A/D converter interrupt and updating of the LEDs on PORTB. The first thing the routine does is to check if the A/D interrupt flag is set. If it is not, the interrupt was caused by some other peripheral, and the program returns to the main routine with interrupts re-enabled. If the interrupt was caused by the A/D converter, the A/D result register is read, and the value put on the LEDs. The A/D interrupt flag is then reset, and the peripheral interrupts are enabled. The routine then waits for the sample time (2*TAD), starts the next conversion, and returns with global interrupts enabled. Service_int Interrupt Service Routine A/D caused interrupt? No Yes Get A/D Value Display on LEDs Reset A/D Flag Re-enable Periph Ints Delay for 2*Tad (SetupDelay) (SetupDelay) Start A/D Conversion Return Figure 4.5: Service Interrupt DS30374D-page 14 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Chapter 5. I2C/EEPROM Demo The iic.asm program demonstrates the use of the I2C bus. The program writes 0 through FFh to each address of the serial EEPROM, and then reads back the value. The LEDs indicate the data presently being written. If an error occurs, all of the LEDs flash. For more information on I2C operation of the SSP module, please refer to the PICmicro Mid-range MCU Family Reference Manual for an operational description and a list of related application notes. For more information on serial EEPROM, please refer to the Technical Library CD-ROM. For detailed information on the PICDEM 2 hardware, please refer to Appendix A. PORT B LEDs 7 RN2 6 5 4 3 2 1 0 RN1 U2 U1 PIC16C73 (28-pin Device) EEPROM C10 U4 PICDEM 2 DEMO BOARD PIC16C64/74 (40-pin Device) ©1994 Figure 5.1: I2C/EEPROM Demo 2001 Microchip Technology Inc. DS30374D-page 15 PICDEM 2 User’s Guide 5.1 SSP Module This section presents the flowcharts to implement a software I2C master mode in hardware. For MSSP operation, refer to Section 5.2. 5.1.1 Main Routine The main routine is actually preceded by several register file, bit and vector assignments (Figure 5.2). The program begins by configuring PORTB as outputs and PORTC as inputs. The output data value will be read from PORTB, so it is initialized to one. PORTC is cleared to set SCL and SCA low when not in tri-state. This is important as I2C is an open-drain bus. That is, only the zero values are actually driven to the bus. Ones are transmitted by making the pin an input (tristate) and allowing the pullup resistor to pull the line high. Data is transmitted in this manner by initializing the SCL and SDA port pins to zero and then writing the output value to the corresponding TRIS bit. A one written to the bit causes the pin to tristate pulled high and a zero causes it to become an output, driven low. Interrupts are not used in this program, so they are disabled. Also, the SSP is configured to enable I2C master mode. The write/read loop begins with the initialization of the EEPROM address to 00h, and the device address to A0h. Then the write loop executes by writing the output data value to each address in the EEPROM (Figure 5.3). After the write loop, the EEPROM address and device address are re-initialized for read. The read loop executes by reading data values for each EEPROM address and verifying their accuracy (Figure 5.4). After the read loop, the output data value is incremented by one and this value displayed, via PORTB, on the LEDs. Then the write/read loop begins again. If an error is encountered when writing or reading the EEPROM, or if an EEPROM value read is incorrect, the program jumps to the error loop, which flashes the LEDs (Figure 5.5). DS30374D-page 16 2001 Microchip Technology Inc. I2C/EEPROM Demo Assignments Start Configure PORTB and PORTC Enable I2C master mode Disable Interrupts Initialize output data value Initialize EEPROM data address Set EEPROM I2C address Write EEPROM Initialize EEPROM data address Set EEPROM I2C address Read EEPROM Increment output data value and display on LEDs Figure 5.2: Main Routine 2001 Microchip Technology Inc. DS30374D-page 17 PICDEM 2 User’s Guide Begin Write loop (WRBYTE) Yes Write Error? Errorloop No Increment Address Yes End of EEPROM? No End Write loop Figure 5.3: Write EEPROM DS30374D-page 18 2001 Microchip Technology Inc. I2C/EEPROM Demo Begin Read loop (RDBYTE) Yes Read Error? Errorloop No Yes Data value incorrect? Errorloop No Increment Address Yes End of EEPROM? No End Read loop Figure 5.4: Read EEPROM Turn off all LEDs Wait about 60 ms Change state of all LEDs Figure 5.5: Errorloop 2001 Microchip Technology Inc. DS30374D-page 19 PICDEM 2 User’s Guide 5.1.2 WRBYTE and RDBYTE Routines The WRBYTE and RDBYTE routines write and read one byte to the serial EEPROM device, respectively. Both routines begin by generating a start bit and then transmitting the slave address and word address. To write to the EEPROM, data followed by a stop bit is transmitted. To read the EEPROM, another start bit and the slave address is transmitted, followed by a data read and transmission of a stop bit. The received data is stored in a file register. Move Slave address to transmit buffer Generate Start Bit (BSTART) Transmit Slave address (TX) Move Word address to transmit buffer Transmit Word address (TX) Move Data to transmit buffer Transmit Data (TX) Generate Stop Bit (BSTOP) Return Figure 5.6: Write Byte DS30374D-page 20 2001 Microchip Technology Inc. I2C/EEPROM Demo Move Slave address to transmit buffer Generate Start Bit (BSTART) Transmit Slave address (TX) Move Word address to transmit buffer Transmit Word address (TX) Begin Read (BSTART) Transmit Slave address (TX) Receive Data (RX) Generate Stop Bit (BSTOP) Save data from buffer to file register Return Figure 5.7: Read Byte 2001 Microchip Technology Inc. DS30374D-page 21 PICDEM 2 User’s Guide 5.1.3 TX and RX Routines The TX and RX routines transmit and receive 8 data bits, respectively. Data is transmitted/received one bit at a time by left bit-shifting the transmit/receive buffer. A counter, set initially to 8, is decremented until all 8 bits of data are sent/received. Finally, acknowledgment bits are received/transmitted. In the case of transmission, if an acknowledgment is not received, an error flag is set. Set counter for eight bits Default bit out = 0 If shifted bit = 0, data bit = 0 else data bit = 1 Send Bit (BITOUT) Rotate transmit buffer left No 8 bits transmitted? Yes Read acknowledge bit (BITIN) Acknowledgment Received? No ERR Yes Return Figure 5.8: Transmit DS30374D-page 22 2001 Microchip Technology Inc. I2C/EEPROM Demo Set counter for eight bits Clear receive buffer Rotate transmit buffer left Receive Bit (BITIN) Default bit out = 0 If shifted bit = 0, data bit = 0 else data bit = 1 No 8 bits transmitted? Yes Send acknowledge bit (BITOUT) Return Figure 5.9: Receive 2001 Microchip Technology Inc. DS30374D-page 23 PICDEM 2 User’s Guide 5.1.4 BITOUT and BITIN Routines The BITOUT routine performs single-bit data transmission from the PICmicro to the serial EEPROM. The BITIN routine performs single-bit data reception from the serial EEPROM to the PICmicro. 5.1.5 BSTART and BSTOP Routines The BSTART and BSTOP routines generate the start and stop bits, respectively. 5.1.6 Delay and Err Routines The Delay routine provides a 10.78 ms delay. The Err routine identifies errors. DS30374D-page 24 2001 Microchip Technology Inc. I2C/EEPROM Demo 5.2 MSSP Module This section presents flowcharts to implement communication with Serial EEPROM using the MSSP module in master mode. For SSP operation, refer to Section 5.1. 5.2.1 Main Routine The main routine is actually preceded by several register file, bit and vector assignments (Figure 5.2). The program begins by configuring PORTB as outputs and PORTC as inputs. The output data value will be read from PORTB, so it is initialized to one. The next part of the code initializes the MSSP module for master I2C mode. The slew rate control is disabled and the clock rate is set to 100 kHz. Both the RC3 and RC4 pins are made inputs as the MSSP module will control the data direction. Interrupts are not used in this program, so they are disabled. Also, the MSSP is configured to enable I2C master mode. The write/read loop begins with the initialization of the EEPROM address to 00h, and the device address to A0h. Then the write loop executes by writing the output data value to each address in the EEPROM (Figure 5.3). After the write loop, the EEPROM address and device address are re-initialized for read. The read loop executes by reading data values for each EEPROM address and verifying their accuracy (Figure 5.4). After the read loop, the output data value is incremented by one and this value displayed, via PORTB, on the LEDs. Then the write/read loop begins again. If an error is encountered when writing or reading the EEPROM, or if an EEPROM value read is incorrect, the program jumps to the error loop, which flashes the LEDs (Figure 5.5). 2001 Microchip Technology Inc. DS30374D-page 25 PICDEM 2 User’s Guide Assignments Start Configure PORTB and PORTC Enable I2C master mode Disable Interrupts Initialize output data value Initialize EEPROM data address Set EEPROM I2C address Write EEPROM Loop Initialize EEPROM data address Set EEPROM I2C address Read EEPROM Loop Increment output data value and display on LEDs Figure 5.10: Main Routine DS30374D-page 26 2001 Microchip Technology Inc. I2C/EEPROM Demo Write EEPROM Loop (WrEEPROMLoop) Send Start Bit Send Slave Address NO Send Restart Ack? YES Send EEPROM Address Send Data Send Stop Bit Increment PORTB, Data, and Address Address >127 NO YES End Write Loop Figure 5.11: Write EEPROM Loop 2001 Microchip Technology Inc. DS30374D-page 27 PICDEM 2 User’s Guide Begin Read loop (RdEEPROMLoop) Send Start Bit Send Slave Address NO Ack? Send Restart YES Send EEPROM Address Send Stop Bit Send Start Bit Send Slave Address Send Restart NO ACK? YES Read Data Byte Data = PortB? NO ErrorLog YES Increment PortB and Address Address >127? YES End RdEEPROMLoop Figure 5.12: Read EEPROM Loop DS30374D-page 28 2001 Microchip Technology Inc. I2C/EEPROM Demo Turn off all LEDs Wait about 100 ms Change state of all LEDs Figure 5.13: Errorloop 2001 Microchip Technology Inc. DS30374D-page 29 PICDEM 2 User’s Guide NOTES: DS30374D-page 30 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Chapter 6. LCD Demo The kbd4bit.asm and kbd8bit.asm programs demonstrate how to interface to an LCD module in both the 4-bit and 8-bit interface modes. The programs read the keypad and output the keypresses to the LEDs and the LCD module. Two include files on the disk, lcd4bit.asm and lcd8bit.asm, have all of the routines necessary to run the display. For more information on LCD operation, please refer to Interfacing PICmicro Microcontrollers to an LCD Module - AN587. For detailed information on the PICDEM 2 hardware, please refer to Appendix A. LCD DSPLY PORT B 7 RN2 6 5 4 3 14 13 2 1 LEDs 2 1 J3 0 U2 LCD R6 R5 RN1 U1 PIC16C73 (28-pin Device) PIC16C64/74 (40-pin Device) Keypad RN4 RN3 J4 PICDEM 2 DEMO BOARD ©1994 KEYPAD 1 Figure 6.1: LCD Demo 2001 Microchip Technology Inc. DS30374D-page 31 PICDEM 2 User’s Guide Any 3x4 or 4x4 keypad may be used, such as C&K part number 4B01H322PCFQ available from Newark Electronics. Figure 6.2 shows typical connections for the keypad. 1 2 3 C 4 5 6 D 7 8 9 E A 0 B F 4X4 KEYPAD, C&K® 8 7 6 5 1 2 3 4 PICDEM 2 J4 A87 A86 A85 A84 A80 A81 A82 A83 P/N 4B01H322PCFQ Figure 6.2: Keypad Connections DS30374D-page 32 2001 Microchip Technology Inc. LCD Demo Many different LCD modules may be used. One is the 16-character-by-2-line Optrex DMC-16207N available from Digi-Key. Figure 6.3 shows the connections to the LCD module. Table 6.1 shows the signal connections for the LCD connector on the PICDEM 2 board. Table: 6.1 LCD Connection Signals PICDEM 2 Pin No. Symbol Signal 1 VSS Ground 2 VCC +5V 3 VEE LCD Contrast 4 RS Register Select 5 R/W Read/Write 6 E Enable 7 • • 14 DB0 • • DB7 Data bit 0 Data bit 7 +5V J3 1 VSS 2 VCC 3 VEE 4 A9 5 A/W 6 E DB0 • • • DB7 7 • • • 14 LCD Module 1 2 3 4 5 6 0.16V RA1 RA2 RA3 7 RD0 • • • 14 RD7 PICDEM 2 Figure 6.3: LCD Connections 2001 Microchip Technology Inc. DS30374D-page 33 PICDEM 2 User’s Guide 6.1 4-Bit Interface 6.1.1. Main Routine (kbd4bit.asm) The program initializes the ports, keypress variables and LCD, then goes into an infinite loop where it looks for keypresses from the keyboard. When it receives one, it relays the ASCII value of the key to the LCD routine for display, then returns to look for another keypress. Start Configure PORTA,B,D Initialize Keypress variables Initialize LCD module (LCDInit) Check for keypress (ScanKbd) No Keypress occurred? Yes Display key on LCD (SendChar) Figure 6.4: Main Routine DS30374D-page 34 2001 Microchip Technology Inc. LCD Demo 6.1.2. ScanKbd Routine (kbd4bit.asm) This routine scans the keyboard for a keypress. When it detects one, it returns the ASCII value of the key. Yes Keypress occurred on last scan? No Set Row Counter Yes No Keypress? No Blank LEDs Get Row Information Debounce Key Display last keypress on LEDs Determine column, row of key and get ASCII value (DEC_TABL) Return Figure 6.5: Keyboard Scan 2001 Microchip Technology Inc. DS30374D-page 35 PICDEM 2 User’s Guide 6.1.3. DEC_TABL Routine (kbd4bit.asm) This routine is basically a look-up table that returns the ASCII value of the received keypress. 6.1.4. LCDInit Routine (lcd4bit.asm) This routine initializes the LCD module. Configure PORTA Configure PORTD Power-up and Set-up Sequence (SetupDelay) Send commands to LCD (SendCmd) 4-bit interface, 2 lines of 5 x 7 characters Display on, cursor on Clear display Set entry mode inc, no shift Address DDRAM upper left Return Figure 6.6: LCD Initialization Routine 6.1.5. SetupDelay Routine (lcd4bit.asm) This routine is basically a decrementing variable loop. The variable is initialized with a value and then decremented in a loop until it reaches zero value. Then it jumps out of the loop and returns to the calling routine. 6.1.6. SendCmd Routine (lcd4bit.asm) This routine sends a command to the LCD. It splits the command into upper and lower nibbles (4 bits) and sends these to the LCD, upper nibble first. 6.1.7. BusyCheck Routine (lcd4bit.asm) This routine checks the LCD busy flag. It returns only when not busy. 6.1.8. SendChar Routine (lcd4bit.asm) This routine sends a character to the LCD. It splits the character into upper and lower nibbles (4 bits) and sends these to the LCD, upper nibble first. DS30374D-page 36 2001 Microchip Technology Inc. LCD Demo 6.2 8-Bit Interface 6.2.1. Main Routine (kbd8bit.asm) The program initializes the ports, keypress variables and LCD, then goes into an infinite loop where it looks for keypresses from the keyboard. When it receives one, it relays the ASCII value of the key to the LCD routine for display, then returns to look for another keypress. Start Configure PORTA,B,D Initialize Keypress variables Initialize LCD module (LCDInit) Check for keypress (ScanKbd) No Keypress occurred? Yes Display key on LCD (SendChar) Figure 6.7: Main Routine 2001 Microchip Technology Inc. DS30374D-page 37 PICDEM 2 User’s Guide 6.2.2. ScanKbd Routine (kbd8bit.asm) This routine scans the keyboard for a keypress. When it detects one, it returns the ASCII value of the key. Yes Keypress occurred on last scan? No Set Row Counter Yes No Keypress? No Blank LEDs Get Row Information Debounce Key Display last keypress on LEDs Determine column, row of key and get ASCII value (DEC_TABL) Return Figure 6.8: Keyboard Scan DS30374D-page 38 2001 Microchip Technology Inc. LCD Demo 6.2.3. DEC_TABL Routine (kbd8bit.asm) This routine is basically a look-up table that returns the ASCII value of the received keypress. 6.2.4. LCDInit Routine (lcd8bit.asm) This routine initializes the LCD module. Configure PORTA Configure PORTD Power-up and Set-up Sequence (SetupDelay) Send commands to LCD (SendCmd) 8-bit interface Display on, cursor on Clear display Set entry mode inc, no shift Address DDRAM upper left Return Figure 6.9: LCD Initialization Routine 6.2.5. SetupDelay Routine (lcd8bit.asm) This routine is basically a decrementing variable loop. The variable is initialized with a value and then decremented in a loop until it reaches zero value. Then it jumps out of the loop and returns to the calling routine. 6.2.6. SendCmd Routine (lcd8bit.asm) This routine sends a command to the LCD. 6.2.7. BusyCheck Routine (lcd8bit.asm) This routine checks the LCD busy flag. It returns only when not busy. 6.2.8. SendChar Routine (lcd8bit.asm) This routine sends a character to the LCD. 2001 Microchip Technology Inc. DS30374D-page 39 PICDEM 2 User’s Guide NOTES: DS30374D-page 40 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Chapter 7. USART Demo The usart.asm program demonstrates the USART peripheral. The program echoes the values received through the serial port back to the host computer. Values are also displayed on the LEDs. The program operates at 9600 baud, 1 stop bit, and no parity. For more information on USART module operation, please refer to the PICmicro Mid-range MCU Family Reference Manual for an operational description and a list of related application notes. For detailed information on the PICDEM 2 hardware, please refer to Appendix A. PORT B LEDs 7 RN2 6 5 4 3 2 1 0 RN1 U2 U1 J1 1 R14 C11 RS-232 U3 C13 C12 C15 C14 PIC16C73 (28-pin Device) PIC16C64/74 (40-pin Device) PICDEM 2 DEMO BOARD ©1994 Figure 7.1: USART Demo 2001 Microchip Technology Inc. DS30374D-page 41 PICDEM 2 User’s Guide 7.1 Main Routine The main routine sets up PORTB for LED display and configures the USART module. When data is received over the RS-232 communication line, an interrupt is generated and the program jumps to the IntVector routine. Start Configure PORT B Enable Receive Interrupt Set up USART 9600 Baud at 4MHz Async, high baud rate TX Continuous RX Data Received? Yes IntVector No Figure 7.2: Main Routine DS30374D-page 42 2001 Microchip Technology Inc. USART Demo 7.2 IntVector Routine The interrupt service routine reads the transmitted data, displays the value on the LEDs, and transmits the same data back to the sender. This routine also checks for receive errors, and jumps to the RcvError routine if any are found. It also determines if the interrupt is other than a receive interrupt, and returns to the main program if it is. IntVector Interrupt Service Routine Yes Receive Error? RcvError No Yes Non-USART interrupt? No Read data, display on LEDs, and echo back to PC Return Figure 7.3: Interrupt Vector Routine 2001 Microchip Technology Inc. DS30374D-page 43 PICDEM 2 User’s Guide 7.3 RcvError Routine The receive error routine clears and then resets the USART receive status bit. It indicates that an error has occurred by lighting all the LEDs before returning to the main program. RcvError Clear and Reset USART receive status Light all LEDs Return Figure 7.4: Receive Error Routine DS30374D-page 44 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Appendix A. Hardware Detail The PICDEM 2 hardware is extremely simple and is intended to illustrate the ease of use of various PICmicro MCUs. The PICDEM 2 features the following hardware elements: A.1 Processor Sockets Although two sockets are provided, only one device may be used at a time. • 40-pin socket • 28-pin socket A.2 Display Eight red LEDs are connected to PORTB of each processor type. The PORTB pins are set high to light the LEDs. These LEDs may be disconnected from PORTB by removing jumper J6. One green LED is provided to determine whether there is power to the PICDEM 2 board (LED lit) or not (LED off). A.3 Power Supply There are three ways to supply power to PICDEM 2: • A 9V battery can be plugged into J8. • A 9V, 100mA unregulated AC or DC supply can be plugged into J2. • A +5V, 100mA regulated DC supply can be connected to the hooks provided. In-circuit emulator users have a regulated +5V power supply available in the logic probe connector and can easily connect to the hooks on PICDEM 2 (Red probe to +5V and Black probe to GND). Note 1: The exact power up sequence listed in Getting Started (Chapter 2) of this guide must be followed. 2: The PICDEM 2 kit does not provide a power supply. 2001 Microchip Technology Inc. DS30374D-page 45 PICDEM 2 User’s Guide A.4 RS-232 Serial Port An RS-232 level shifting IC has been provided with all necessary hardware to support connection of an RS-232 host through the DB9 connector. The port is configured as DCE, and can be connected to a PC using a straight through cable. The PIC16C74 has its RX and TX pins tied to the RX and TX lines of the MAX232A. A.5 Switches Three switches provide the following functions: • S1 - MCLR to hard reset the processor • S2 - Active low switch connected to RA4 • S3 - CCP1 for capture of timer Switches S1 and S3 have debounce capacitors whereas S2 does not, allowing the user to investigate debounce techniques. When pressed, the switches are grounded. When idle, they are pulled high (+5V). A.6 Oscillator Options • RC oscillator (2MHz approximately) supplied. This oscillator may be disabled by removing jumper J7. • Pads provided for user furnished crystal and two capacitors. • Socket provided for clock oscillator. Provisions are also provided for an external crystal oscillator for Timer1. A.7 Analog Input A 5K ohm potentiometer is connected through a series 470 ohm resistor to AN0. The pot can be adjusted from VDD to GND to provide an analog input to the parts with an A/D module. DS30374D-page 46 2001 Microchip Technology Inc. Hardware Detail A.8 Serial EEPROM A 24LC01 1K (128x8) serial EEPROM is included on the board to illustrate I2C bus concepts. Provisions for an ACCESS.bus™ connector (J5) and associated resistors (R8-R13) are wired in parallel with the serial EEPROM. For more information on the serial EEPROM, please refer to the most recent version of the Technical Library CD-ROM. A.9 Keypad Header J4 is a nine pin header which may be used as a keypad interface. Any 3x4 or 4x4 keypad may be used. For an example keypad, see LCD Demo (Chapter 6). A.10 LCD Header J3 is a 14 pin header which may be used as an LCD module interface. Many different LCD modules may be used. For more information on LCD modules, refer to the manufacturers’ data sheets. For an example LCD, see LCD Demo (Chapter 6). A.11 Sample Devices A sample part programmed with a simple program is included in the PICDEM 2 kits. Table 10-1 lists the I/O features and port connections for each processor type. TABLE A-1: PORT CONNECTIONS LEDs RS-232 TX/RX S1 S2 S3 Pot R16 Keypad Connector 28-pin PORTB RC6/RC7(1) MCLR RA4 RC2 RA0(2) PORTB — RC3/RC4 40-pin PORTB RC6/RC7 MCLR RA4 RC2 RA0 PORTB PORTA/D RC3/RC4 Processor Note LCD Control/ Data EEPROM/ ACCESS.BUS 1: PIC16C64 does not have a USART module. 2: PIC16C64 does not have an A/D module. 2001 Microchip Technology Inc. DS30374D-page 47 PICDEM 2 User’s Guide A.12 Board Layout and Schematics The following figures show the parts layout (silkscreen) and schematics for the PICDEM 2 board. PICDEM 2 Parts Layout 6 5 4 2 1 C8 C4 C5 (RX) (TX) R2 RESET C6 R18 Y3 R8 R9 R10 R11 R12 R13 C10 C15 R17 C12 PIC16C64/74 RA4 RC2 (SDA) (SCL) (OSI) (OSO) +5V C2 R4 C3 C19 PIC16C73 U4 C14 GND J7 Y1 C13 RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0 RD7 RD6 RD5 RD4 RD3 RD2 RD1 RD0 RC7 RC6 RC5 RC4 RC3 RC2 RC1 RC0 MCLR RA0 RA1 RA2 RA3 RA4 RA5 RE0 RE1 RE2 NC GND U1 +5V U2 C18 U3 R6 R5 RN1 +5V C17 J3 0 Y2 U5 R14 C11 3 14 13 GND 1 7 RN2 R15 9V BATTERY CR1 + 2 1 +5V J1 CR2 J6 C16 J2 +9V IN LCD DSPLY PORT B PWR GND U8 C7 Figure A-1: RA0 S1 PICDEM 2 DEMO BOARD S2 C9 R7 R19 J5 C1 R1 R3 TM ©1994 S3 RN4 RN3 J4 KEYPAD 1 Note 1: U2 is for use with any 28-pin PIC16CXXX or PIC18CXXX device. 2: U1 is for use with any 40-pin PIC16CXXX or PIC18CXXX device. DS30374D-page 48 2001 Microchip Technology Inc. Figure A-2: S1 +5V RA 1 2 3 4 5 6 R1 4.7K C1 0.1 R17 470 +5V 470 R18 470 +5V 1 2 3 4 5 6 7 8 R3 4.7K S2 +5V R4 4.7K U1 RB J7 +5V RE 13 12 31 OSC1 C3 20PF RE0 RE1 RE2 RD0 RD1 RD2 RD3 RD4 RD5 RD6 RD7 RC0 RC1 RC2 RC3 RC4 RC5 RC6 RC7 VDD VDD MCLR RA0 RA1 RA2 RA3 RA4 RA5 RB0 RB1 RB2 RB3 RB4 RB5 RB6 RB7 OSC1 OSC2 VSS VSS RE0 RE1 RE2 8 9 10 19 20 21 22 27 28 29 30 15 16 17 18 23 24 25 26 RD0 RD1 RD2 RD3 RD4 RD5 RD6 RD7 OS0 OS1 RC2 SCL SDA RC5 TX RX 14 OSC2 1 2 3 RA1 4 RA2 5 RA3 6 7 8 9 10 11 12 13 14 RN3 9 PIN HEADER 4 3 4 3 4 3 D2 D3 D4 D5 D6 D7 DS30374D-page 49 D8 D9 J6 RN3 RB4 RN3 RB5 RN3 RB6 RN3 RB7 RN1 RB0 RN1 RB1 RN1 RB2 RN1 RB3 RN2 RB4 RN2 RB5 RN2 RB6 RN2 RB7 Y2 1 2 3 4 5 6 7 8 C8 0.1 20 NMCLR 1 RA0 RA1 RA2 RA3 RA4 RA5 2 3 4 5 6 7 RB0 RB1 RB2 RB3 RB4 RB5 RB6 RB7 21 22 23 24 25 26 27 28 U2 OSC1 RA0 RA1 RA2 RA3 RA4 RA5 OSC2 RB0 RB1 RB2 RB3 RB4 RB5 RB6 RB7 RC0 RC1 RC2 RC3 RC4 RC5 RC6 RC7 OSC1 10 OSC2 +5V C11 (RC0) OSO (RC1) OSI RC2 (RC3) SCL (RC4) SDA RC5 (RC6) TX RX (RC7) OSO OSI RC2 SCL SDA RC5 TX RX 0.1 U3 VCC V+ TX 11 T1IN 10 T2IN RX 12 R1OUT 9 R2OUT 1 RD0 RD1 RD2 RD3 RD4 RD5 RD6 RD7 J2 1 3 2 R8 10 J5 C7 20pF R10 10 C16 0.01 C2- V- R12 820 4 R14 10 C15 0.1 15 +5V D1 R15 470 LM78L05 U5 CR1 2 IN 4 CR2 1N914 + OUT COM C17 220 + C18 220 Breadboard R13 820 8 VSS 19 VSS PIC16C73 C19 0.1 +9V Battery +5V +5V 6 7 8 9 5 GND 1 3 W02M R9 10 R11 10 C2+ C1- 6 J8 +5V 13 R1IN 8 R2IN GRN POWER +5V Y3 14 T1OUT 7 T2OUT C1+ 3 C13 0.1 J1 1 2 3 4 5 MAX232A C14 0.1 Provision Only, Not Populated TBD C6 20pF 11 12 13 14 15 16 17 18 5 C12 0.1 DJ005A 9 SDA R19 470 VDD MCLR 24LC01B SCL WP VSS 1 2 3 4 5 6 7 8 TXCO +5V 6 7 RD Not Populated OUT C9 0.1 FOR LCD DSPLY U4 VDD A0 A1 A2 X1 +5V Hardware Detail 4 RB0 RB1 RB2 RB3 C5 20PF 8 1 2 3 RC Y1 TBD Notes: Unless otherwise specified, resistance values are in ohms, 5% 1/4W. Capacitance values are in microfarads. 0.1 S3 2 PIC16C64 C4 20PF J3 C10 16 Provision Only KEYBOARD J4 1 2 3 4 5 6 7 8 9 +5V R7 4.7K 330 0.1 11 32 1 2 3 4 5 6 7 33 34 35 36 37 38 39 40 +5V R6 R5 10K NMCLR RA0 RA1 RA2 RA3 RA4 RA5 RB0 RB1 RB2 RB3 RB4 RB5 RB6 RB7 R2 R16 5K +5V C2 RA0 RA1 RA2 RA3 RA4 RA5 PICDEM 2 Schematic 2001 Microchip Technology Inc. +5V PICDEM 2 User’s Guide NOTES: DS30374D-page 50 2001 Microchip Technology Inc. 12 PICDEM 2 USER’S GUIDE Index A A/D Demo ....................................................... 11 A/D Input .............................................. 2, 11, 46 B Board .................................................. 1, 2, 5, 45 Parts Layout ............................................. 48 Power Supply ....................................... 5, 45 Schematic ................................................ 49 Silkscreen ................................................ 48 D Demonstation Board. See Board Demonstation Programs. See Sample Programs USART Demo .......................................... 41 PICDEM 2 Board. See Board PICDEM 2 Kit .................................................... 1 PICSTART® Plus ......................................... 4, 7 PRO MATE® II ............................................. 4, 7 Pushbuttons. See Switches R RC Oscillator ................................................... 46 Reference Documents ...................................... 4 RS-232 .................................................. 2, 41, 46 H Hardware ........................................................ 45 S Sample Devices .................................. 1, 3, 6, 47 Sample Programs ..................................... 1, 3, 6 Schematic ....................................................... 49 SCI .................................................................. 41 SSP Module, I2C Mode ................................... 15 Switches ............................................. 2, 5, 9, 46 I I2C Demo ........................................................ 15 T Tutorial .............................................................. 9 K Keypad ........................................... 2, 31, 32, 47 U USART Demo ................................................. 41 E EEPROM, Serial ................................... 2, 15, 47 L LCD ...................................................... 2, 33, 47 LCD Demo ...................................................... 31 LEDs Green Power ........................................ 2, 45 Red Display .......... 2, 5, 9, 11, 15, 31, 41, 45 M MPASM ........................................................ 4, 7 MPLAB ......................................................... 4, 7 P PIC16C64 I2C Demo ................................................. 15 LCD Demo ............................................... 31 Tutorial Program ........................................ 9 PIC16C74 A/D Demo ................................................ 11 I2C Demo ................................................. 15 LCD Demo ............................................... 31 Tutorial Program ........................................ 9 2001 Microchip Technology Inc. DS30374D-page 51 PICDEM 2 User’s Guide NOTES: DS30374D-page 52 2001 Microchip Technology Inc. Index NOTES: 2001 Microchip Technology Inc. DS30374D-page 53 M WORLDWIDE SALES AND SERVICE AMERICAS ASIA/PACIFIC Japan Corporate Office Australia 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Technical Support: 480-792-7627 Web Address: http://www.microchip.com Microchip Technology Australia Pty Ltd Suite 22, 41 Rawson Street Epping 2121, NSW Australia Tel: 61-2-9868-6733 Fax: 61-2-9868-6755 Microchip Technology Japan K.K. Benex S-1 6F 3-18-20, Shinyokohama Kohoku-Ku, Yokohama-shi Kanagawa, 222-0033, Japan Tel: 81-45-471- 6166 Fax: 81-45-471-6122 Rocky Mountain China - Beijing 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7966 Fax: 480-792-7456 Microchip Technology Consulting (Shanghai) Co., Ltd., Beijing Liaison Office Unit 915 Bei Hai Wan Tai Bldg. No. 6 Chaoyangmen Beidajie Beijing, 100027, No. China Tel: 86-10-85282100 Fax: 86-10-85282104 Atlanta 500 Sugar Mill Road, Suite 200B Atlanta, GA 30350 Tel: 770-640-0034 Fax: 770-640-0307 Austin - Analog 13740 North Highway 183 Building J, Suite 4 Austin, TX 78750 Tel: 512-257-3370 Fax: 512-257-8526 Boston 2 Lan Drive, Suite 120 Westford, MA 01886 Tel: 978-692-3848 Fax: 978-692-3821 Boston - Analog Unit A-8-1 Millbrook Tarry Condominium 97 Lowell Road Concord, MA 01742 Tel: 978-371-6400 Fax: 978-371-0050 Chicago 333 Pierce Road, Suite 180 Itasca, IL 60143 Tel: 630-285-0071 Fax: 630-285-0075 Dallas 4570 Westgrove Drive, Suite 160 Addison, TX 75001 Tel: 972-818-7423 Fax: 972-818-2924 Dayton Two Prestige Place, Suite 130 Miamisburg, OH 45342 Tel: 937-291-1654 Fax: 937-291-9175 Detroit Tri-Atria Office Building 32255 Northwestern Highway, Suite 190 Farmington Hills, MI 48334 Tel: 248-538-2250 Fax: 248-538-2260 Los Angeles 18201 Von Karman, Suite 1090 Irvine, CA 92612 Tel: 949-263-1888 Fax: 949-263-1338 New York 150 Motor Parkway, Suite 202 Hauppauge, NY 11788 Tel: 631-273-5305 Fax: 631-273-5335 San Jose Microchip Technology Inc. 2107 North First Street, Suite 590 San Jose, CA 95131 Tel: 408-436-7950 Fax: 408-436-7955 Toronto 6285 Northam Drive, Suite 108 Mississauga, Ontario L4V 1X5, Canada Tel: 905-673-0699 Fax: 905-673-6509 China - Chengdu Microchip Technology Consulting (Shanghai) Co., Ltd., Chengdu Liaison Office Rm. 2401, 24th Floor, Ming Xing Financial Tower No. 88 TIDU Street Chengdu 610016, China Tel: 86-28-6766200 Fax: 86-28-6766599 China - Fuzhou Microchip Technology Consulting (Shanghai) Co., Ltd., Fuzhou Liaison Office Rm. 531, North Building Fujian Foreign Trade Center Hotel 73 Wusi Road Fuzhou 350001, China Tel: 86-591-7557563 Fax: 86-591-7557572 China - Shanghai Microchip Technology Consulting (Shanghai) Co., Ltd. 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India Liaison Office Divyasree Chambers 1 Floor, Wing A (A3/A4) No. 11, O’Shaugnessey Road Bangalore, 560 025, India Tel: 91-80-2290061 Fax: 91-80-2290062 Korea Microchip Technology Korea 168-1, Youngbo Bldg. 3 Floor Samsung-Dong, Kangnam-Ku Seoul, Korea 135-882 Tel: 82-2-554-7200 Fax: 82-2-558-5934 Singapore Microchip Technology Singapore Pte Ltd. 200 Middle Road #07-02 Prime Centre Singapore, 188980 Tel: 65-334-8870 Fax: 65-334-8850 Taiwan Microchip Technology Taiwan 11F-3, No. 207 Tung Hua North Road Taipei, 105, Taiwan Tel: 886-2-2717-7175 Fax: 886-2-2545-0139 EUROPE Denmark Microchip Technology Denmark ApS Regus Business Centre Lautrup hoj 1-3 Ballerup DK-2750 Denmark Tel: 45 4420 9895 Fax: 45 4420 9910 France Arizona Microchip Technology SARL Parc d’Activite du Moulin de Massy 43 Rue du Saule Trapu Batiment A - ler Etage 91300 Massy, France Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79 Germany Arizona Microchip Technology GmbH Gustav-Heinemann Ring 125 D-81739 Munich, Germany Tel: 49-89-627-144 0 Fax: 49-89-627-144-44 Germany - Analog Lochhamer Strasse 13 D-82152 Martinsried, Germany Tel: 49-89-895650-0 Fax: 49-89-895650-22 Italy Arizona Microchip Technology SRL Centro Direzionale Colleoni Palazzo Taurus 1 V. Le Colleoni 1 20041 Agrate Brianza Milan, Italy Tel: 39-039-65791-1 Fax: 39-039-6899883 United Kingdom Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820 08/01/01 DS30374D-page 54 2001 Microchip Technology Inc. *DS30374D*