Paradyne COMSPHERE 3920Plus Technical Reference Manual page 145

Configure Branch
Table 5-12
(6 of 8)
V.42/MNP/Buffer Configuration Options — Singleport Mode A
SDC Idle Fill: Flag_Fill
Nxt Flag_Fill Mark_Fill
This configuration option only appears when the Async/Sync Mode configuration option is set is to Sync and
Sync Comp Mode configuration option is not set to DirectMode.
Synchronous Data Compression Idle Fill. Determines whether the modem uses an HDLC flag or mark to fill the time
between DTE frame transfers.
Flag_Fill – Causes the modem to fill the time between DTE frame transfers with HDLC flags.
Mark_Fill – Causes the modem to fill the time between DTE frame transfers with marks.
The AT command is S-Register S36 = n, where n is 0 for Flag_Fill and 1 for Mark_Fill.
SDC BitEncoding: NRZ
Nxt NRZ NRZI
This configuration option only appears when the Async/Sync Mode configuration option is set is to Sync and
Sync Comp Mode configuration option is not set to DirectMode.
Synchronous Data Compression Bit Encoding. Determines the type of bit encoding scheme (NRZ or NRZI) the modem
uses when transmitting synchronous DTE data.
NRZ – Causes the modem to use the standard Non Return to Zero bit encoding scheme.
NRZI – Causes the modem to use the Non Return to Zero Inverted bit encoding scheme.
The AT command is S-Register S37 = n, where n is 0 for NRZ and 1 for NRZI.
SyncDTE CRC: Ignore
Nxt Ignore CRC16
This configuration option only appears when the Async/Sync Mode configuration option is set to Sync and the
Sync Comp Mode configuration option is not set to DirectMode.
Synchronous DTE CRC. Determines whether the CRC of the DTE frame is transmitted from modem to modem.
Ignore – No assumption is made about the CRC type. The CRC is transmitted along with the other data in the frame.
16
CRC16 – The CRC is known to be the 16-bit CRC for HDLC frames defined by the ITU-T (generator polynomial x +
12 5
x + x + 1). It is removed from the DTE frame by the sending modem and added to the DTE frame by the receiving
modem.
The AT command for SyncDTE CRC is S22=n, where n is 0 for Ignore and 1 for CRC16.
SDC Delay Min: Off
Nxt Off Rx_Clock
This configuration option only appears when the Async/Sync Mode configuration option is set to Sync and the
Sync Comp Mode configuration option is not set to DirectMode.
Synchronous Data Compression Delay Minimization. Allows the modem to transmit a DTE frame to its DTE in a
discontinuous way to minimize the delay introduced by SDC processing.
Off – The modem does not begin transmitting a frame to its DTE until the entire frame has been received.
Rx_Clock – The modem begins to transmit data from a DTE frame to its DTE even if the end of the DTE frame has not
yet been received by the modem. The receive clock (circuit 115/Pin 17) is clamped when the beginning of a DTE frame
has been transmitted to the DTE and no other data from this DTE frame has been received by the modem. As soon as
data from the current DTE frame can be transmitted to the DTE, the receive clock is released. The Rx_Clock
configuration option appears only if the Tx Clock Source configuration option is set to Internal.
The AT command for Off is #DM0.
The AT command for Rx_Clock is #DM1.
3920-A2-GH30-40 October 1998 5-69