Folks, Thanks for the help with this query. I have been barking up the incorrect tree all along. After doing a hex dump (function of the printer) it transpires that my data string was formatted incorrectly. There was no problem with the serial comms. I was using OxA (\n) instead of 0xD (\r). Why it worked under Hyperterm was because HT was doing the necessary character translations to convert all 0xA to 0xD and I was not aware of it. A comparison between what HT dumped and what my code dumped showed this up. The commands to the printer are terminated with a \r. The command that the printer received was never correctly terminated and this nothing was printed.This led me to believe it was comms.
Hylton ----- Original Message ----- From: "Jason Teagle" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Tuesday, March 16, 2004 12:14 PM Subject: RE: [msvc] A (not so) Quick Comms Question. > > nothing wrong with the command, I assume there is nothing wrong with the > > cable either (home made cable - any one have the specs for a > > rs232 cable to > > device that supports xon/xoff) or hyperterm is working some kind of magic > > that my code isn't. It even works with hyperterm when I turn handshaking > > off. > > If you're using the same cable for Hyperterm as for your own program, then > it can't be the problem. > > > > > I am setting up the dcb block as follows > > > > case EHandshakeSoftware: > > dcb.fOutxCtsFlow = false; // Disable CTS (Clear To Send) > > dcb.fOutxDsrFlow = false; // Disable DSR (Data Set Ready) > > dcb.fDtrControl = DTR_CONTROL_DISABLE; // Disable DTR (Data Terminal > > Ready) > > dcb.fRtsControl = RTS_CONTROL_DISABLE; // Disable RTS (Ready To Send) > > You may want to try various combinations of these. Unfortunately I'm very > sketchy on how to use these, with the exception that RTS must be enabled for > RS485 comms (so not applicable here). Sadly Hyperterm gives up no > information on what these are set at, so that's no help. > > > What else should I be looking for to try and get this printer to recognise > > the communication? > > Well this is essentially a serial port question, I am getting quite > > desperate and any additional advice will be helpful. > > What about the rest of the DCB parameters? Where are they initialised? You > may remember that I said you must set them ALL if you're working on 2K or XP > (or possibly NT). > > -- > Jason Teagle > [EMAIL PROTECTED] > > > > _______________________________________________ > msvc mailing list > [EMAIL PROTECTED] > See http://beginthread.com/mailman/listinfo/msvc_beginthread.com for subscription changes, and list archive.
