This is what Ascend's technical support says about connecting a modem. This interface is a real-time status and configuration interface which not only allows the user to control as wells as monitor the functional behavior and status of the equipment but to do so remotely, as well as locally. Not all modems are directly compatible with this type of interface. Dumb mode causes the modem to ignore data on the RD lead. Auto-answer should be enabled.
Dumb mode is activated by a hardware switch on some modems.
Modems without a hardware switch to set the unit on dumb mode will not work even with the AT commands entered. To make the modem useful, the following Hayes commands will, if supported, accomplish the appropriate software modem configuration. No echo 4. No result messages 6. The pin out for the Control port can be found in the manual provided with your Ascend Multiband.