Installation and Reference Guide HP AdvanceStack 100Base-THub-12TX, Hub-12TXM, and Switch Modules 1997-06

HP Hub-12TX/Hub-12TXM Installation and Reference Guide
C-2 Modem Configuration
Practical Peripherals PM288MT II V.34
At the hub end:
Issue the following AT command:
AT&F0&C2S0=102&D3&W0
At the user end:
Issue the following AT command:
AT&F0&W0