power no reset, how can I write this into my program?

[nigel]

Hello
Firstly I think I should explain, I am a student tiring to teach myself how to program a PIC 16F877 and part of a project. I have now got most of the program working but the rs232 is a problem. If the circuit is reset i.e. the power turned off and on. The PIC does not transmit data, although a newly programmed PIC works fine. I’m sure this is because the program does not reset. But cant find much info on POR functions, is there one?

P.S. How do you use it?
___________________________
This message was ported from CCS's old forum
Original Post ID: 12834

[PCM programmer]

:=Hello
:=Firstly I think I should explain, I am a student tiring to teach myself how to program a PIC 16F877 and part of a project. I have now got most of the program working but the rs232 is a problem. If the circuit is reset i.e. the power turned off and on. The PIC does not transmit data, although a newly programmed PIC works fine. I’m sure this is because the program does not reset. But cant find much info on POR functions, is there one?
:=
-----------------------------------------------------------
Try running the following test program and see if it works.
Make sure that you use these fuse settings. That's important.
The only one that you should change is the "HS". If you're
running at 4 MHz, then change it to "XT".

I think that your problem could be fixed by the BROWNOUT
fuse, or, possibly by the NOLVP fuse. Try this program and
see. I tested it on my demo board, and I can switch the
power on and off quickly, and I get "Hello World" every time.
(It also gives one garbage character at the beginning, but
I'm not concerned about that for this test).

#include "c:\Program Files\Picc\Devices\16F877.h"
#fuses HS, NOWDT, NOPROTECT, PUT, BROWNOUT, NOLVP
#use Delay(clock=8000000)
#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7, ERRORS)

//====================================================

void main()
{

printf("Hello world\n\r");

while(1);
}
___________________________
This message was ported from CCS's old forum
Original Post ID: 12843

[nigel]

:=:=Hello
:=:=Firstly I think I should explain, I am a student tiring to teach myself how to program a PIC 16F877 and part of a project. I have now got most of the program working but the rs232 is a problem. If the circuit is reset i.e. the power turned off and on. The PIC does not transmit data, although a newly programmed PIC works fine. I’m sure this is because the program does not reset. But cant find much info on POR functions, is there one?
:=:=
:=-----------------------------------------------------------
:=Try running the following test program and see if it works.
:=Make sure that you use these fuse settings. That's important.
:=The only one that you should change is the "HS". If you're
:=running at 4 MHz, then change it to "XT".
:=
:=I think that your problem could be fixed by the BROWNOUT
:=fuse, or, possibly by the NOLVP fuse. Try this program and
:=see. I tested it on my demo board, and I can switch the
:=power on and off quickly, and I get "Hello World" every time.
:=(It also gives one garbage character at the beginning, but
:=I'm not concerned about that for this test).
:=
:=#include "c:\Program Files\Picc\Devices\16F877.h"
:=#fuses HS, NOWDT, NOPROTECT, PUT, BROWNOUT, NOLVP
:=#use Delay(clock=8000000)
:=#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7, ERRORS)
:=
:=//====================================================
:=
:=void main()
:={
:=
:=printf("Hello world\n\r");
:=
:=while(1);
:=}


Thanks for the advice. Have now changed the fuse setting on my program and it works perfectly. Thanks Again
___________________________
This message was ported from CCS's old forum
Original Post ID: 12865