8-bit MicrocontrollersのトピックRe: Single-wire SCI mode

Single-wire SCI mode

kosthala — Thu, 05 Apr 2007 16:58:58 GMT

Hello,

In our application we use the MC9S08AW32 and we try to use the single wire mode of SCI.
The code to initialize the SCI is:

      mov   #$A0, SCI1C1
      mov   #$00, SCI1C3
      mov   #$24, SCI1C2   ; enable RECEIVER
      cli

but the SCI is not working. The transmiter is sending data but the
receiver doesn't receive any data at all.
Is there something else we need to know in order to make it work?

Thanks in advance.

Re: Single-wire SCI mode

bigmac — Thu, 05 Apr 2007 20:55:48 GMT

Hello,

For single wire transmit/receive operation, It would be usual to have both transmitter and receiver sections of the SCI enabled - for this the value for SCI1C2 register would need to be $2C. Otherwise, there is little point in selecting-single wire mode for a receive only application.

Additionally, the TXDIR bit within SCI1C3 would need to be set to 1 whenever a byte is sent, and then returned to 0, once the transmission is complete, ready to receive any incoming data.

Regards,

Mac

Message Edited by bigmac on 2007-04-0612:09 AM

Re: Single-wire SCI mode

kosthala — Thu, 12 Apr 2007 15:54:58 GMT

Hello Mac,

Sorry for the delayed answer (i was away from civilization for a few days). Anyway, your solution was
perfect
Thank you very much.