ECE 3724/CS 3124 Experiment Supplementary Files Page

All of the lab exercises refer to supplementary files or ZIP archives; these are found below.

• Experiment 1, Student ID CPU, ZIP archive , FAQ .
• Experiment 2, PIC18, MPLAB Intr , FAQ .
1. mptst.asm
2. shownum.asm
• Experiment 3, PIC assembly language programming #1, FAQ , Compiling these files with Visual Studio 6.0 or Visual C .NET.
1. op.zip archive
2. loop.zip archive
• Experiment 4, PIC assembly language programming #2
1. intop.zip archive
2. compare.zip archive
• Experiment 5, PIC assembly language programming #3, FAQ .
1. strlcase.asm
2. strflip.c
3. strup.c
4. strxchg.c
5. strcnt.c
6. cstrcnt.c
• Experiment 6, PIC Startup, FAQ .
1. Prototyping Walkthru for PIC Startup Schematic , supplements the instructions in the lab manual with a step-by-step connection diagram of the startup schematic.
2. Changing PIC18 configuration bit settings using the COLT Bootloader instead of JOLT, see this document if you the COLT bootloader instead of JOLT.
3. config.h (needed by all files)
4. delay.h (DelayMS, DelayUs)
5. ledflash.c
6. ledflash.hex (HSPLL)
7. ledflash_a200.hex (HSPLL)
8. serial.c (needed by most files)
9. echo.c
10. echo.hex (HSPLL)
11. echo_a200.hex (HSPLL)
12. reset.c
• Experiment 7, Serial vs. Parallel IO, FAQ .
1. serio.c (putch/getch subroutines)
2. ledsw1 (LED/Switch IO example)
• Experiment 8, Interrupt-driven IO
1. root_rxfifo.c
2. rxfifo_test1.txt
3. intfsm.c , a fairly simple LED/Switch IO, ISR only looks for falling edges on pushbutton input.
4. intfsm_new.c , a more complex example, ISR looks for both falling and rising edges by changing the active interrupt edge between states. See Interrupt notes for state chart.
• Experiment 9, The I2C Bus, FAQ .
1. i2cmsu.c
2. i2cmsu.h
3. i2c_memutil.c
4. i2cmemtst.c
• Experiment 10, Data Conversion, FAQ .
1. dactst.c
• Experiment 11, Timers #1
1. sqwave.c
2. mtrpwm.c
3. pcmgen.c
• Experiment 12, Timers #2

Careful: The IR detector is sensitive to noise, which can cause it to emit pulses with no IR source present. Use the scope to ensure that your IR receiver is not doing this. If this happens, try isolating the noise source by unplugging chips from the board until the errant pulses disappear. In the past, it was found that an LM386 with an OPEN input pin (pin 3) caused this problem. Removing the LM386 or grounding the input caused the problem to disappear. I have also had this noise problem occur if I did not have a decoupling capacitors (0.1 uF capacitors) placed between Vdd and GND on the PIC18 (put this as close as possible to the chip as you can).

1. swdetov.c Measures pulse-width
Either this file or the next file can be used as a starting point for decoding IR space-width data.
2. irdet_biphase.c Biphase IR decode example from textbook. If you want to try this code on your PIC18 board, the Radio Shack Universal remote control must be programmed for a Phillips VCR, which is manufacturer code 333. This code can be used as a starting point for your space-width decoding code. This is only a suggestion, you do not have to use this code as a starting point. Warning: Biphase decoding is more complex than space-width decoding; this code decodes biphase by detecting both falling and rising edges on the IR input waveform. Space-width decoding only requires that you detect every falling edge since you are trying to detect the difference between successive bit periods. If you use this code as a starting point, you will be simplifying its operation, and you will have to understand how the original code works order to know what to remove.
• Experiment 13, Audio Record/Playback
1. audio.c
2. ZIP archive with some WAV files

CAUTION: If you do not have input A2 of the 24LC515 (Serial EEPROM) tied to VDD then when your writes get to the 2nd block of EEPROM, they will fail (you will get a watchdog timeout error because the device will not respond).