CompuServe Thread

Whoppee!!

1 messages in this thread
#625From: Don CurtisDec 6, 1985 1:33 AM
Another thing you may watch out for is that CIS uses CRC protocol (or at least attempts it) when sending or receiving files via XMODEM. The receiving end of the transfer controls CRC by "requesting" it. If your term program can't handle CRC by at least NAK'ing the attempted CRC handshake, you will not be able to do uploads. The attempted handshake is the ASCII char "C", if (as a "sender") you get a "C" instead of a NAK on the first attempt at handshake, NAK it and continue to NAK the "C"'s until CIS decides to switch to std. handshake and sends a NAK instead. From that point on, everything is standard. Also, once in CRC (if you intend to handle it by using it instead), after the initial handshake (send C–> from receiver get SOH from sender <–) you will then switch to std handshake of ACK and SOH (or NAK and SOH for errors). Hope this makes sense to you. Don Curtis