Stepper project problems - CCS C PCM Compiler

[Raven]

Hi All

We are a group of mechanical engineer students who has some problems with a stepper motor project.

Our project is described here:
http://www.pfg.dk/pub/index.php/user/content/view/full/138?PHPSESSID=93146569ae1dc31efa9bfebe87763d55

The problem is with the controlling of the stepmotors. Since we are mechanical Engineer Students the world of electronic is tough. We have chosen a solution with an stepper controller which takes advantage of the PIC 16C73.
The controller is this one:
http://www.doc.ic.ac.uk/~ih/doc/stepper/smack-jnr/

The problem is that the source code is not compiled and the CCS C PCM compiler is pretty expensive for a one time use only for a student :-)
The sourcecode can be seen here:
http://www.doc.ic.ac.uk/~ih/doc/stepper/smack-jnr/smack_pic.c

Is there anybody out there who would help us and compile the program with CCS C PCM compiler?

We are using the Pic 16C73A, and we have the pic burner

Any help would really be greatly appriciatet!

Best Regard and thanks in advance
Kristoffer Raun

Stud. Polyt.
s011530@student.dtu.dk

[Mark]

You should be able to use a 16F876 instead. There is a demo of the compiler that will allow to you compile the code and since the device is flash based you can reprogram it. The demo might only be for the 16F877 but it should still work in the 16F876.

[dyeatman]

I get a "Not Enough RAM for Variables" message when I try to compile this for you.

However, it compiles with no problems for the 16C76 here are the statistics (notice that Worst Case RAM is the problem, you only have 192, so you may be able to fix this with some reorganization):

ROM used: 2545 (31%)
2048 (25%) including unused fragments

2 Average locations per line
6 Average locations per statement

RAM used: 150 (41%) at main() level
205 (56%) worst case

Lines Stmts % Files
----- ----- --- -----
823 454 100 C:\My Download Files\smack_pic.c
215 0 0 C:\CCS_C\PICC\devices\16c76.h
----- -----
2076 908 Total

Page ROM % RAM Functions:
---- --- --- --- ----------
0 14 1 0 @GETCH_BIU_1
0 172 7 4 InitialiseMotors
0 42 2 3 rda_handler
0 28 1 1 tbe_handler
0 5 0 0 allowNewMessage
0 37 1 4 startMotor
0 194 8 6 timer1_handler
0 21 1 3 stopMotor
0 25 1 5 @MUL1616
0 630 25 6 UpdateMotorQ
0 103 4 6 CheckLimits
1 1203 47 0 main

Segment Used Free
--------- ---- ----
00000-00003 4 0
00004-00046 67 0
00047-007FF 1271 706
00800-00FFF 1203 845
01000-017FF 0 2048
01800-01FFF 0 2048

[Raven]

Hi Dyeatman

You wrote you tried to compile it to 16C76- Is there any difference between this and Pic 16C73A when compiling.


Thanks for your help so far! :-)



Kristoffer Raun

[dyeatman]

I did this purely because the 76 has more memory since the 73 compile came up short on memory and to see if there were any other compile time code problems, which there were not.

Code wise the program should compile fine on the 73 when you get the memory usage down a bit. Whether it runs correctly is another story....can't do much about that here since I don't have any of the hardware...

[Raven]

Hi Dyeatman

Thanks a lot for your good answer!

I'm a beginner into this PIC'ing, but i'm wondering if it's possible to compile it , even thought that there isn't enough space for the variables?


Anyway i will try to get the memory usage down and hopefully this will work.

How much does the compiled program use at the moment and how much do i have to cut it down?

Thanks in advance

Kristoffer Raun

[dyeatman]

According to the stats I provided in the earlier reply:

ROM used: 2545 (31%)
2048 (25%) including unused fragments

2 Average locations per line
6 Average locations per statement

RAM used: 150 (41%) at main() level
205 (56%) worst case

The problem is in the last line above (205 worst case) meaning that you require 205 RAM positions worst case but only 150 in the main program (you have 192 RAM to play with in the 73) sooooo you need to work on eliminating/combining/reusing variables as much as possible to get the worst case number down to below 192 (-13 decrease) which should be possible with a little analysis.

You have plenty of ROM left (73 has 4096) so RAM is your main issue at this point.

Good Luck!
dave

[Raven]

Hi Dave

Thanks a lot - I will give it a try to reuse some of the variables.
Tell me - what happens if i use this program and put it into the pic, and the used ram amount exceed 192?

Best Regards
Kristoffer

[dyeatman]

Theoretically, the program should not exceed the worst case spec the compiler generates. Therefore the prgram should not compile if the compiler sees a possiblility of running out of RAM. However, that doesn't mean it can't happen(never say never!). If it does, a program crash will likely occur depending on circumstances or at best a program anomaly of some kind (??).

Dave

[Raven]

Hi Dyeatman

Thank again for your answer.
I have looked thru the code and have found a limit switch-function which we aren't going to use - i will delete this function from the code and hopefully this should give me the last 13.... :-)


Another question - I see in the code that the baudrate is fixed to 1200 baud.

#use rs232(baud=1200,xmit=PIN_c6, rcv=PIN_c7,errors)

Is it possible for the pic to use a higher baud rate with the 16C73A ?

#use rs232(baud=9600,xmit=PIN_c6, rcv=PIN_c7,errors)
What's the limit?

Best Regards

/Kristoffer

[Mark]

With a 10MHz crystal you can do 57600 with a small % error. If 9600 is fast enough for you, that would be ideal.

[Raven]

Hi


Thank you Mark for your answer - i have set it to 9600, this should be adequate.

I have removed a limit function to control some limitswitches that we dont need. This could give the needed space.

http://www.pfg.dk/smack_pic.c

Best Regards
Kristoffer

[Mark]

This is what I get with an older version of the compiler

CCS PCM C Compiler, Version 3.089, 12084

Filename: test.LST

ROM used: 2457 (60%)
Largest free fragment is 851
RAM used: 141 (73%) at main() level
187 (97%) worst case
Stack: 4 worst case (2 in main + 2 for interrupts)

So yes, it compiled

[dyeatman]

I get the same statistics for 3.182 (as shown below) so you seem to have that much taken care of. It compiles fine for me as well...

Dave

=============
ROM used: 2140 (52%)
985 (24%) including unused fragments

2 Average locations per line
5 Average locations per statement

RAM used: 141 (73%) at main() level
187 (97%) worst case

Lines Stmts % Files
----- ----- --- -----
779 428 100 C:\My Download Files\smack_pic.c
215 0 0 C:\CCS_C\PICC\devices\16c73.h
----- -----
1988 856 Total

Page ROM % RAM Functions:
---- --- --- --- ----------
0 13 1 0 @GETCH_BIU_1
0 124 6 3 InitialiseMotors
0 30 1 2 rda_handler
0 24 1 1 tbe_handler
0 5 0 0 allowNewMessage
0 24 1 3 startMotor
0 160 7 5 timer1_handler
0 18 1 2 stopMotor
0 32 1 5 @MUL1616
0 559 26 5 UpdateMotorQ
1 1063 50 0 main

[Guest]