rfl@oddjob.uchicago.edu (Bob Loewenstein) (10/31/90)
I have been using the serial port on the mac for years with no problem. I now have a problem using a high speed modem (Microcom v.32c and also v.42bis) at MNP7 and MNP10 protocols. The baudrate between the mac and the modem is 38400. The remote modem is connected to a Sun also at 38400. The problem is that every so often (about 1/60000 bytes) I get a -89 error (SCC receiver error, framing, parity..) from the serial driver IOResult. I have tested with both DTR hardware handshaking and no handshaking with the same results. The problem does not happen at baudrates less than 38400. Anyone have any ideas? A while back I tested mac <-> mac communications at 38400 and 57600 baudrates (no modem in between) and did not see these errors.
rfl@oddjob.uchicago.edu (Bob Loewenstein) (10/31/90)
The serial problem of framing errors from the modem port at 38400 baud has to do with appletalk running. If I turn off appletalk, then the problem goes away. Is this documented anywhere?