Ricoh M281 Series Service Manual page 945

Bit 3 Bit 2
0
0
1
1
4 PSTN cable equalizer
(V.8/V.17 RX mode: External)
0: Disabled
1: Enabled
5 Not used
6 Parameter selection for dial tone
detection
0: Normal parameter
1: Specific parameter
7 Not used
G3 Switch 08 - Not used (do not change the settings)
G3 Switch 09 - Not used (do not change the settings)
No Function
0-1 Maximum allowable carrier drop
during image data reception
SM
Setting length of wire between the modem and
the telephone exchange.
0 None
Also, try using the cable equalizer if one
or more of the following symptoms
1 Low
occurs.
0 Medium
Communication error with error codes
such as 0-20, 0-23, etc.
1 High
Modem rate fallback occurs frequently.
Keep this bit at "1".
Do not change the settings.
0: This uses the fixed table in the ROM
for dial tone detection.
1: This uses the specific parameter
adjusted with SRAM (69ECBEH -
69ECDEH). Select this if the dial tone
cannot be detected when the "Normal
parameter: 0" is selected.
Do not change the settings.
G3 Switch 0A (SP No. 1-105-011)
These bits set the acceptable modem
carrier drop time.
111

This setting is not effective in
V.34 communications.
Comments
D255/D256 FAX OPTION
Bit Switches - 4