How to use 2nd UART

[Guest]

How do you switch between UARTs for those devices that have 2 UARTs?

For example, putc(c), or getc(), how do you tell the code which UART to use?

Also, how do you handle the interrupt service routine? Is there an ISR for each UART?

The manual is silent on all this.

Steve

[PCM programmer]

1. Specify a "stream" in each #use rs232() statement.

2. Then use fputc, fgetc, fprintf, etc., and specify the stream to be used.
See the CCS manual for descriptions of these functions.

3. Use #INT_RDA for the 1st UART. Use #INT_RDA2 for the 2nd UART.
See the .H file for your PIC for a list of #INT_ directives. Look near the
end of the file.

[Guest]

Ahhhh! I see.

Can you tell me why the compiler error for "com2" in the set_uart_speed call?

#use rs232(UART1,baud=9600,parity=N,xmit=PIN_C6,rcv=PIN_C7,bits=8,errors,stream=com1)
#use rs232(UART2,baud=9600,parity=N,xmit=PIN_G1,rcv=PIN_G2,bits=8,errors,stream=com2)
...
set_uart_speed( 1200,(which_port==com1) ? com1:com2);

But yet, this line compiles:

set_uart_speed( 1200, com2);

It didn't like using "which_port" as an argument, even though it's set like this:

which_port = com1;

It says it needs to be a constant.

Steve

[PCM programmer]

The CCS stream functions only accept a constant for the 'stream' value.

[Guest]

I got that. But the two lines seems equivalent to me. In any case, I modified my routine to the following. The same #use rs232 defines in my previous post are still there and unchanged.

[PCM programmer]

Download the CCS manual:
http://www.ccsinfo.com/downloads/ccs_c_manual.pdf

In the section on set_uart_speed(), it says:

[Guest]

Ok, I screwed that up. But the compiler was flagging "com1" and "com2" as the error, so I wasn't looking at baud.

Thanks for your help.