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Manufacturer: U.S. Robotics
Model: Sportster
Latest Firmware Revision Tried: Supervisor 4.1 (04/22/93)/DSP 10 (03/23/93)
Recommended Firmware Revisions: Supervisor 4.1 (04/22/93)/DSP 10 (03/23/93)
Last Updated: Date: 1997/10/13 04:02:00 $


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Firmware revisions numbers appear to be meaningless; only the data stamps are useful.

Newer v.34 models include Class 2.0 fax support.

• Timing problems have been observed with older firmware revisions; if you have problems, be sure to verify the firmware revision.
• When sending DCD is raised when carrier is first received, but it is then dropped from the first HDLC receive until the point where the initial training is sent (from that point on DCD is asserted); this can be a problem because there is no way to override this behaviour which means that the host must be capable of ignoring DCD for sending to function correctly
• In testing the modem locked up during transmission to a Multi-Tech 1432BA modem and failed to respond to the host dropping DTR

28.8 FAX V34 modem

• Rather than trying to upgrade Firmware, a "degrade" maybe preferable, since anything newer than the following is not totally compliant with Class 2.0 :

         Product type           US/Canada External
         Options                V32bis,V.FC,V.34
         Fax Options            Class 1/Class 2.0
         Clock Freq             20.16Mhz
         Eprom                  256k
         Ram                    32k
  
         Supervisor date        04/18/95
         DSP date               03/31/95
   
         Supervisor rev         6.0.5
         DSP rev                1.0.9
        

• A suggestion, which works for some, is to set the DCE/DTE-Rate down to 19200bps

33.6 Voice Modem

• Due to the constant reports of problems with Class 2.0, currently the advice is to use Class 1 mode.
• A fix, and your mileage may vary, is to insert this initialization command into the modem config file :
  Class2NRCmd: AT+FNR=1,1,1,0 #setup status reporting command
• US Robotics support suggest that an EPROM date of 5/?/96 or greater is advisable. (This date is obtainable from the ATI7 command).

Modem Index ZyXEL U-1496