Ositech comm Trumpcard Data/Fax Modem User's Manual And Reference page 75

S38 — Delay Before Forced Disconnect
Range
Default
This register specifies the delay between the modem's receipt of the
Hangup (H) command to disconnect (or ON-to-OFF transition of /DTR if
the modem is programmed to follow the signal) and the disconnect
operation. For an error-correction connection, this register can be used to
ensure that data in the modem buffer is sent before the modem
disconnects. If S38 is set between 0 and 254, the modem will wait that
number of seconds for the remote modem to acknowledge all data in the
modem buffer before disconnecting. If time expires before all data is sent,
the NO CARRIER result code will be issued to indicate that data has been
lost. If all data is transmitted prior to timeout, the response to the H0
command will be OK. If S38 is set to 255, the modem data does not
timeout, and continues to attempt to deliver data in the buffer until the
connection is lost, or the data is delivered.
S46 — Protocol Selection
Range
Default
Controls selection of compression.
The following actions are executed for the given values:
S46 = 136
S46 = 138
User's Guide and Reference
0-255 seconds
20
136 or 138
136
Execute error correction protocol with no
compression.
Execute error correction protocol with compression.
In addition to V.42bis, the modem also implements
MNP4 data compression. V.42bis is used only with
LAPM, and MNP5 only with MNP4.
Modem Command Reference
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