Lantronix 1-T Network Card User Manual


 
Troubleshooting Modem Configuration Checklist
B - 7
B.5 Modem Configuration Checklist
Most modem problems are caused by cabling mistakes or incorrect modem
conÞguration. However, the following items should be veriÞed after any
modem conÞguration, and re-checked when there is modem trouble.
¥ The modem must disconnect immediately when DTR is de-asserted.
¥ The modem must assert CD (or DSR, if connected) when connected
to another modem. It must not assert CD when disconnected. The
modem may optionally assert CD during outbound dialing.
¥ The modem and MSS must agree on the ßow control method and
baud rate scheme.
¥ The modem must not send result codes or messages to the server
except optionally during outgoing calls.
¥ The modem should be set to restore its conÞguration from non-
volatile memory when DTR is dropped.
¥ The modem should be conÞgured to answer the phone if incoming
connections are to be supported. Generally this is done with the
ats0=1 command.
¥ The modem should not be conÞgured to answer the phone unless
the MSS asserts DTR.
¥ MSS Modem control must be enabled. Using modems on ports
without modem control enabled will lead to security problems.
The MSS Autobaud feature should be enabled only when required.