New C18 3.0+ Compatible FRC Code

[kaszeta]

Originally Posted by Kevin Watson

I had a look at your code and it looks like the problem is your limit() function, which is returning a 16-bit integer when it should return an unsigned 8-bit byte.

This is probably one of the big things to watch for, even for experienced programmers. The MPLAB/PIC18 platform (and embedded platforms in general) are a lot less tolerant of type mismatches than your usual programming.

[billbo911]

Originally Posted by Kevin Watson

You're waiting because I'm deep in procrastination mode and haven't finished the first cut of the documentation yet <grin>.
-Kevin

I think someone needs to pull a high priority interrupt and put everything else you are doing on hold! This should be your top priority, cuz I said so.

"Procrastination mode" I wonder if FIRST will use that to replace Hybrid mode next year?

[lukevanoort]

Originally Posted by billbo911

"Procrastination mode" I wonder if FIRST will use that to replace Hybrid mode next year?

Well, in the past, the difference wouldn't be very noticeable...

[Kevin Watson]

Originally Posted by Jon236

BTW, would you think that using 4 interrupts,INT's 3-6, at 128 ints/sec (every ~8ms) would be overstressing the processor?

I depends on what else is executing on the processor, but in general you shouldn't have a problem.

-Kevin

[Kevin Watson]

Originally Posted by billbo911

I think someone needs to pull a high priority interrupt and put everything else you are doing on hold! This should be your top priority, cuz I said so.

Okay, here is a snapshot of the current build that includes support for encoders and gyro:

http://kevin.org/frc/ifi_frc_beta_4.zip

*Please* help me out and have a look at the code and documentation (start with readme.txt) and provide feedback before I go public with the code on my website, which I'd like to do on Friday or early Saturday. If you can, follow the directions in readme.txt to build the code and test with your encoder(s) and/or gyro and report any problems here. Thanks.

-Kevin


Edit: Code has been released and is available here: http://kevin.org/frc.

-Kevin

[Mike Mahar]

Kevin,
In your gyro initialization code in teleop.c, you have two static ints that you use as counters. (i, j) You increment both every time through the function. When you wish to print out the gyro you have the following:

	
if(i == 35 && j >= 300)

Since i has been incrementing all along, it will be equal to j. The next time i == 35 j will also be equal to 35. Putting i = 0 into the

if(j == 300)

body should fix that. You also need to put i = 0 into the body of the

if(==35 && i >= 300)

statement if you aren't using the encoder code.

[Kevin Watson]

Originally Posted by Mike Mahar

Kevin,
In your gyro initialization code in teleop.c, you have two static ints that you use as counters. (i, j) You increment both every time through the function. When you wish to print out the gyro you have the following:

    
if(i == 35 && j >= 300)

Since i has been incrementing all along, it will be equal to j. The next time i == 35 j will also be equal to 35. Putting i = 0 into the

if(j == 300)

body should fix that. You also need to put i = 0 into the body of the

if(==35 && i >= 300)

statement if you aren't using the encoder code.

Thanks, I'll have a look to see if I can clean it up a bit.

-Kevin

[billbo911]

In the README.TXT, in the section to enable the ISR's in ifi_frc.h, (bullet # 3)the description is misleading, or the file is incorrect.

3) Enable the interrupt service routines associated with each encoder
channel at the top of ifi_frc.h.

When looking at the file, the lines do not indicate that you are enabling an ISR.

// #define ENABLE_INT_1			// enable if using encoder channel 1
// #define ENABLE_INT_2			// enable if using encoder channel 2
// #define ENABLE_INT_3			// enable if using encoder channel 3...

Documentation error, code error, reader misunderstanding error???

[Kevin Watson]

Originally Posted by billbo911

Documentation error, code error, reader misunderstanding error???

Given the comments above and alongside those #defines, I don't see how a user wouldn't be able to figure it out:

// Remove the comment slashes from one or more of the following lines to
// enable the respective external interrupt(s) and/or timer(s). By doing
// so, you only enable the code within ifi_frc to become part of your
// software build.
// #define ENABLE_INT_1 // enable if using encoder channel 1
// #define ENABLE_INT_2 // enable if using encoder channel 2
// #define ENABLE_INT_3 // enable if using encoder channel 3
// #define ENABLE_INT_4 // enable if using encoder channel 4
// #define ENABLE_INT_5 // enable if using encoder channel 5
// #define ENABLE_INT_6 // enable if using encoder channel 6

I'd be happy to change it, but I don't fully understand the problem...

-Kevin

[billbo911]

I just saw the answer in encoder.c.
Sorry for the confusion. My bad.
I hate it when I misinterpret instructions like that. Oh well, blame it on sleep deprivation.

[bronxbomber92]

Is it recommended to use this code over the default, or should teams wait to use until it's out of its beta stages?

[Jon236]

Kevin,

what changes should be made to the Vex C templates to run under 3.10? I'm getting library errors.

[Kevin Watson]

Originally Posted by Jon236

Kevin,

what changes should be made to the Vex C templates to run under 3.10? I'm getting library errors.

The library needs to be built with the new compiler. Until then we're stuck with C18 2.4.

-Kevin

[Loki1989]

Can we use MPlab 8.0 to use 3.10 to compile? I need to know Because I cant find 7.21

[kaszeta]

Originally Posted by Loki1989

Can we use MPlab 8.0 to use 3.10 to compile? I need to know Because I cant find 7.21

Yes. That's the exact setup I'm using.