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pom
Joined: 25 Nov 2004 Posts: 30 Location: Germany
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Can commands? |
Posted: Fri Dec 10, 2004 7:13 am |
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Hello there,
I want to communicate between to PICs, for example a 18F258, by CAN. Unfortunately I don't know how to do this and I don't find anything in help or in examples for this. Can someone tell me just one command for using the CAN-Bus, so that I can search for this command instant just searching for "CAN"?
I think, if I know one command and find it in help, I will also be able to find all the others.
Thank you in advance, pom |
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Mark
Joined: 07 Sep 2003 Posts: 2838 Location: Atlanta, GA
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Posted: Fri Dec 10, 2004 8:15 am |
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My examples folder has at least 3 example files for CAN. They all begin with EX_CAN |
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pom
Joined: 25 Nov 2004 Posts: 30 Location: Germany
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Posted: Mon Dec 13, 2004 3:44 am |
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My example folder has none of these.
If there were examples with this name, I would not have asked for some commands.
But I have just an example called EX_PBUSM.C. It is an example for "Generic Pic to Pic message transfer program over one wire". I think, it is not the same. Am I right? |
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pom
Joined: 25 Nov 2004 Posts: 30 Location: Germany
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Posted: Mon Dec 13, 2004 3:50 am |
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Maybe someone can put the examples to this forum, so that I can see them. Or otherwise, someone can read them out and tell me some instruction which are used in there.
It would be very nice, I don't know what to do. |
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ckielstra
Joined: 18 Mar 2004 Posts: 3680 Location: The Netherlands
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Posted: Mon Dec 13, 2004 4:10 am |
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Which version of the CCS ccompiler do you have? I think the examples were introduced in v3.186 or 3.187 and were improved in a later version.
No special CAN commands were introduced in the compiler, all functionality is in the supplied driver files. That's why you won't find information in the help files.
For more examples on implementing CAN commands you can also have a look at the Microchip website. |
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pom
Joined: 25 Nov 2004 Posts: 30 Location: Germany
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Posted: Tue Dec 14, 2004 10:08 am |
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I don't know how to explain, but I can't find an entry to the programming of the can-communication .
At last I have an example for this and I have a Peak PCAN-hardware to connect the can-bus to the computer. But neither do I get messages on the computer nor can I send some from the Computer to the PIC.
I produced this code:
#if defined(__PCH__)
#include <18F258.h>
#fuses HS,PUT,NOWDT,NOPROTECT,NOLVP,NOBROWNOUT
#use delay(clock=20000000)
#use rs232(baud=57600, xmit=PIN_C6, rcv=PIN_C7) // Jumpers: 8 to 11, 7 to 12
#endif
#include <bootloader.h>
#include <can-18xxx8.c>
void main(void) {
struct rx_stat rxstat;
int i=5;
int in_data[8];
int32 tx_id;
int tx_len;
for (i=0; i++; i>8){
in_data[i]= 0;
}
printf("\r\nApplication program version 1.01 \r\n");
while (i<10){
can_init();
can_getd(tx_id, &in_data[0], tx_len,rxstat);
printf("angekommen %u \n\r",&in_data[0]);
}
}
First question: Why does the code just work once? i is always smaller than 10. I changed it to while (true) and it worked some times, but also stopped after a while.
Second question: By the RS232 the Pic writes in_data[0] to the screen. But it is always 8, independent from the message I try send.
I am near to the point to give up. Unfortunately I really need the solution of this problem. Please help me. |
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ckielstra
Joined: 18 Mar 2004 Posts: 3680 Location: The Netherlands
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Posted: Tue Dec 14, 2004 11:54 am |
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First remark: When posting code please use the 'code' button from this forum, this will ensure the layout of your code is preserved.
Second remark: You never answered the question which compiler version you are using.
Third: Quote: | I don't know how to explain, but I can't find an entry to the programming of the can-communication | I can see you found ex_can.c, so what exactly don't you understand?
Four: Code: | for (i=0; i++; i>8){
in_data[i]= 0;
} |
This bug clears a large part of your RAM area and makes your program go crazy. I guess you meant: Code: | for (i=0; i<8; i++){
in_data[i]= 0;
} |
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PCM programmer
Joined: 06 Sep 2003 Posts: 21708
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Posted: Tue Dec 14, 2004 1:04 pm |
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I think you should buy the "1 year maintenance" for the CCS PCH
compiler. Then you will get all the required CAN example files and
driver files. There are several of them, and CCS doesn't allow us
to post them on this forum. There are maybe one or two things
that you might have to modify, to make the CCS drivers work with
your CAN interface, but they have been discussed on this forum and
you can find them in the archives.
The PCH maintenance is only $99 USD. Because the dollar is so low,
I think that price must seem really cheap in Europe.
http://www.ccsinfo.com/ccscorder.shtml#CCompiler |
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