Lantronix 1-T2 User Manual

Troubleshooting

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.

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The modem must disconnect immediately when DTR is de-asserted.

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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.

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The modem and MSS must agree on the ßow control method and 

baud rate scheme.

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The modem must not send result codes or messages to the server 

except optionally during outgoing calls.

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The modem should be set to restore its conÞguration from non-

volatile memory when DTR is dropped.

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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.

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The modem should not be conÞgured to answer the phone unless 

the MSS asserts DTR.

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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.