time@oxtrap.aa.ox.com (Tim Endres) (12/01/89)
Thank you to all who helped with the Telebit problem connecting at 19200. It turns out that the value of register 51 was set in a way that caused it to connect to the A/UX at 9600. Setting register 51=254 fixed the problem. New problem: I can upload XMODEM and get 800cps, not great, *and* not as good as expected. I can upload ZMODEM and get 1700cps. This looks like the best I am going to do according to most people I have talked to. BUT! I can download XMODEM and get 1300 cps!!! Now this is more what I expected from XMODEM! This is also a great discrepancy between XMODEM down and up. This says to me that the A/UX machine can not keep the same pace coming in as going out. Not that this surprises me greatly, but does anyone have an explaination? It seems ZMODEM would suffer a similar defficiency, but it does upload and download at about the same rate. When we watch the Telebit RD/SD data lights, we see the Mac side do: "zoom stop... zoom stop... zoom stop..." while the A/UX side does: "steady blinking, not as fast as the Mac side." When the Mac side is done, the A/UX side continues for some time (buffer in Telebit I presume) and finally sends ACK for EOF. We are using XON/XOFF on the A/UX input side, but not the A/UX output (i.e. stty -ixon ixoff).