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Hi David, At 14:57 5/04/98 +0100, David Woolley wrote: >I hope everyone is clear what Phase B is. Firstly it is not an error. It >is the stage of the conversation where the machines are exchanging their >characteristics at 300bps. As such, it is unlikely that there will be >any transmission errors or interface underruns/overruns, so any error >either represents the modem sending something the remote end doesn't >understand, or possibly, for class 2, the modem receiving something >invalid from the local host. There's unlikely to be any transmission errors between the modem and the local host, but if the phone line is bad the communication with the remote machine can easily fail. Something i forgot about till recently which might be causing the Transmit Phase B errors on my machine is that in Austalia the busy tone is apparently fairly close to a facsimile training tone, the sending modem sometimes get confused thinking it had got a fax machine and started into Phase B trying to communicate with the engaged signal. This is ok as i haven't actually paid for the call, the modem is just confused. > >I suppose a loose interpretation of the TSI might upset a remote machine, >and cause this sort of error, but the Rockwell documents I'm using don't >go down to enough detail here. (Loose interpretation means anthing except >an international format or local phone number. Loose interpretations may >well be technically illegal, but are widely supported.) I have a copy of T30, if i am reading correctly the only characters officially allowed are 0-9, space and the '+' character. I dont imagine this will bother many machines but anyway - Robert