changing rs232 baud rates

[Neil Grant]

hi,

I need to setup a modem that could be set at any baud rate so I tried to do:

#use rs232(baud=19200,xmit=C6,rcv=C7,...
printf("\n\rAT+IPR=2400")
#use rs232(baud=9600,xmit=c6,...
printf("\n\rAT+IPR=2400")

to make sure it is set to 2400 but all the #use rs232 statements create code at the beginning of the program which the pic runs through at boot up and sets the speed to 19200 then 9600 ... etc and the pic ends up in the last speed rather than changing between them. I have tried using streams eg:

#use rs232(baud=19200,xmit=C6,rcv=C7,stream=str1)
#use rs232(baud=9600,xmit=C6,rcv=C7,stream=str2)
fprintf(str1,...
fprintf(str2,...

but this results in the same problem.

the only way I have managed to change speed is by manually writing to the SPBRG register. I am using the 16F876 and the lastest version of mplab (6.3) and picc (3.173)

regards

Neil Grant
___________________________
This message was ported from CCS's old forum
Original Post ID: 144517103

[R.J.Hamlett]

:=hi,
:=
:=I need to setup a modem that could be set at any baud rate so I tried to do:
:=
:=#use rs232(baud=19200,xmit=C6,rcv=C7,...
:=printf("\n\rAT+IPR=2400")
:=#use rs232(baud=9600,xmit=c6,...
:=printf("\n\rAT+IPR=2400")
:=
:=to make sure it is set to 2400 but all the #use rs232 statements create code at the beginning of the program which the pic runs through at boot up and sets the speed to 19200 then 9600 ... etc and the pic ends up in the last speed rather than changing between them. I have tried using streams eg:
:=
:=#use rs232(baud=19200,xmit=C6,rcv=C7,stream=str1)
:=#use rs232(baud=9600,xmit=C6,rcv=C7,stream=str2)
:=fprintf(str1,...
:=fprintf(str2,...
:=
:=but this results in the same problem.
:=
:=the only way I have managed to change speed is by manually writing to the SPBRG register. I am using the 16F876 and the lastest version of mplab (6.3) and picc (3.173)
:=
:=regards
:=
:=Neil Grant
Look in the manual, at 'set_uart_speed'...

Best Wishes
___________________________
This message was ported from CCS's old forum
Original Post ID: 144517105

[Douglas Kennedy]

:=hi,
:=
:=I need to setup a modem that could be set at any baud rate so I tried to do:
:=
:=#use rs232(baud=19200,xmit=C6,rcv=C7,...
:=printf("\n\rAT+IPR=2400")
:=#use rs232(baud=9600,xmit=c6,...
:=printf("\n\rAT+IPR=2400")
:=
:=to make sure it is set to 2400 but all the #use rs232 statements create code at the beginning of the program which the pic runs through at boot up and sets the speed to 19200 then 9600 ... etc and the pic ends up in the last speed rather than changing between them. I have tried using streams eg:
:=
:=#use rs232(baud=19200,xmit=C6,rcv=C7,stream=str1)
:=#use rs232(baud=9600,xmit=C6,rcv=C7,stream=str2)
:=fprintf(str1,...
:=fprintf(str2,...
:=
:=but this results in the same problem.
:=
:=the only way I have managed to change speed is by manually writing to the SPBRG register. I am using the 16F876 and the lastest version of mplab (6.3) and picc (3.173)
:=
:=regards
:=
:=Neil Grant
This works for me
#use rs232(STREAM=GPS,baud=9600, xmit=PIN_c6, rcv=PIN_c7, parity=N, bits=8)
and in the code where you need to switch baud rate
set_uart_speed(4800,GPS);
___________________________
This message was ported from CCS's old forum
Original Post ID: 144517106