There are many modems with the Rockwell AC/K56 firmware : for example

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Manufacturer: Diamond Multimedia Model: SupraExpress 56
Manufacturer: Multitech Model: MT5600ZDX
Manufacturer: Zoom Model: 56Kx 2949
Last Updated: Date: 1999/03/24 23:07:11 $


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This firmware can be identified by the modem interrogation results:

• AT+FMFR?

  ROCKWELL

• AT+FMDL?

  AC/K56

• No comment.

Initial versions excluded Class 2 support. It is not known at what firmware version Class 2 support was re-introduced
For example:

Multitech MT5600ZDX bought in 1998 without Class 2 support:
• ATI6 RCV56DPF-PLL L8571A Rev 19.00/19.00

Zoom 56Kx bought in early 1999 with Class 2 support
• ATI6 RCV56DPF L8570A Rev 47.24/47.24

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