Experimenting with IR Remotes using a PIC running BoostC Project
Experimenting with IR Remotes using a PIC running BoostC Project
EARLY DRAFT - NOT READY
- Name: Experimenting with IR Remotes using a PIC running BoostC Project
- Status: early draft -- do not read
- Technology: PIC microcontroller, slavaged IR reciever, running with code in BoostC
- Author: russ_hensel ( where you can find an email address to reach me )
- Summary: A PIC16F877A project that reads IR remote controls. Runs with a PC running a terminal program.
- Last revision Dec 21 2008 – Early Draft.
- Download: see section below.
Platform: PIC16F877A using BoostC connected via rs232 to a PC running a terminal program, or as an alternative running a Java program developed especially to control the PIC ( still under development ). The PIC chip is supplemented with a dual op amp connected as two schmidt triggers, there is of course a stepper motor.
Hardware
Schematic
Parts -- this is not up to date, working on it
| Part | Details |
| Power supply | Not shown, 5 volts, you can use a higher voltage with a voltage regulator. There is a suitable power supply in the PIC based Stepper Motor Dancing Analog Clock |
| PIC16F877A | My favorate 16 series part, relatively lots of memory and pins. Bigger than you need, but only about 8 bucks. Try with an 18 series part, should not be hard and will leave you more up to date. Let me know. Other parts of the PIC circuit not discussed here. |
| Power supply splitting resistors, form a pseodo ground at about 2.5 volts. | 100 more or less |
| RIN | about 5 to 10 K |
| RFB | feedback resistor should be about 4 times higher than the input resistor |
Command Interface
All commands ( except stop should be terminated with a carriage return ) Note that the command interface is not very smart, giving parameters that are out of range my blow the whole program up. If so reboot the PIC. Do not send a new command ( except stop ) until earlier commands have been completed ( actually you can get ahead some if you are careful )
| Command | Code | Notes, PIC Response |
|---|---|---|
| Report version | v<cr> | Version of the PIC software something like:
Serial Stepper Test ver July 4 2008 |
| Reset | r<cr>
reset the counters and the log of the encoder. Response something like "Reset Count" | |
| Log report | l<cr> | Report the log of data. A series of binary numbers, comma delimited. |
| Report on all parameters | r | Delimited by commas something like: |
| Position of the encoder | p<cr> | report the position of the encoder, and other counts of encoder activity. |
| Stop | ! | Should almost immediately stop long running commands of which there are currently none. Response Stopped. |
| Other, not understood commands | xxx | Responds with "!Bad Command = xxx" if the command is not understood. |
Notes on terminal program set up.
- Baud rate should be 19.2K 8N1
- Most terminal programs can be set to treat a carriage return as a carriage return line feed. Do it.
Some terminal programs will not transmit in lower case ( all our commands are lower case ) unless specially set to do so. Set it to allow lower case.
Microcontroller Program
Design =
Compiling
The zip file contains the entire source bootst project. Unzip into a directory and open in source boost. Set the target to 16F877A. See the comments in the program header for other setup before compiling. After compiling my compiler reports something like:
Memory Usage Report
- RAM available:368 bytes, used:248 bytes (67.4%), free:120 bytes (32.6%),
- Heap size:120 bytes, Heap max single alloc:95 bytes
- ROM available:8192 words, used:1239 words (15.2%), free:6953 words (84.8%)
The program seems to be safely under the 2K free compiler limit.
Other Things to Try
Additions/Changes/Modification
- The 877A is way overkill for this project unless you make it do a bit more. Note that only 1 input pin ( with interrupt capabability ) plus the serial lines are really used.
Possibly useful links
This program uses my: Serial Communications Library -- BoostC and 16F877A
More information on serial communications with microcontrollers: Microcontroller Serial Communications Articles
A free terminal program, I like this much better than hyperterminal:
Welcome to our Free Download/New Products Page!
http://www.rs485.com/psoftware.html
BoostC – I think the free version is enough to compile the program: SourceBoost Technologies http://www.sourceboost.com/
Download
pending, not at: Version 1 zip file: StepperTest_v1.zip
Comment, Questions, Contributions?
Email me russ_hensel, or use the talk page for this topic. All feedback is welcome.
