" TPDD uses 9600 and 19200 reliably only because it operates in small packets and no screen updates."
TPDD drives and emulator file services work with no flow control at high speeds because of the half duplex, request/response nature of the TPDD protocol... it's client driven, and the client is either requesting or focused solely on receiving the response to the last request. The server never sends more than about 128 bytes, and never unbidden. Since the client is driving (as opposed to the server which could easily blast the 100 with an entire file in some other protocol), the responses are small and the client isn't really doing anything else while receiving the response. It will never be overrun. Of course that's very inefficient. Only one half of a two way channel is ever in use. And it's constantly starting and stopping. Consider a protocol like zmodem... the peer can adapt to a fast receiver and stream an entire file as one packet. -- John. >
