brian@spock (Brian Nickerson) (03/07/90)
I have been having been doing some serial port software and ran across some problems that I hope someone has a solution to. The first one was that I couldn't change my baud rate while in the middle of a connection. I tried using int 14h with ah=0. This seemed to hang the port so I tried a direct write to the divisor latch. Hung again. I know several communication packages that you can change the baud settings at anytime during the connection. Does anyone know why my methods would hang the port ? The other problem I've had was in detecting rings. I decided that it might be safer to monitor the modem status instead of relying on the modem's RING message. Again, I used int14h with ah=3. I was masking off the Delta RI bit. The 8250 specs indicate that once the register is read that all the Delta bits are reset. This didn't seem to be the case because it stayed set as long as there was ringing on the line (i.e. Delta RI = RI). I tried doing a direct read of the modem status register and it made no difference. If anyone has experienced similar problems and might be able to help, please send a reply to my uunet address. -- Brian Nickerson Please send all replies to: uunet!mitel!spock!brian