Black Box MD1641A, MD1640A manual Speed Conversion Commands, Enq/Ack Pacing Commands

Pacing on (either RTS on/off or Xon/Xoff depending on the setting of &E4 or &E5).*

Pacing off*

SERIES II INTELLIGENT DATA/FAX MODEMS

Enq/Ack Pacing Commands:

&E8 = Enq/Ack method of pacing off*

&E9 = Enq/Ack method of pacing on

Normal Mode Modem Flow Control Commands:

&E10 = Normal Mode Modem Flow Control off*

&E11 = Normal Mode Modem Flow Control (Xon/Xoff) on

Computer-or Terminal-Initiated Flow Control (Pacing) Commands: &E12 =

&E13 =

Data Compression Commands:

&E14 = Data Compression disabled

&E15 = Data Compression enabled*

*Factory-default setting.

5.4.11 Speed Conversion Commands

Speed conversion is a necessary part of data compression since data must be presented to the modem faster than it can handle data, if data compression is to be effective.

Speed conversion allows the Series II Modem to communicate at one speed over the phone line, and at another speed at the RS232C interface. The speed (also referred to as “data rate” or “baud rate”) can be fixed at the RS232 interface independently of the baud rate of the on-line transmissions.

In addition to data compression, another popular application for speed conversion involves an auto-answer Series II Modem connected to a computer that does not have autobaud capability. This means that the

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