Ricoh D131 Service Manual page 1047

Maximum allowable frame interval
4 during image data reception.
0: 5 s 1: 13 s
5 Not used
Reconstruction time for the first line in
6 receive mode
0: 6 s 1: 12 s
7 Not used
G3 Switch 0B Not used (do not change the settings).
G3 Switch 0C Not used (do not change the settings).
G3 Switch 0D Not used (do not change the settings).
SM
This bit set the maximum interval
between EOL (end-of-line) signals and
the maximum interval between ECM
frames from the other end.
Try using a longer setting if error code
0-21 is frequent.
Do not change the settings.
When the sending terminal is controlled
by a computer, there may be a delay in
receiving page data after the local
machine accepts set-up data and sends
CFR. This is outside the T.30
recommendation. But, if this delay
occurs, set this bit to 1 to give the
sending machine more time to send data.
Refer to error code 0-20.
ITU-T T.30 recommendation: The first line
should come within 5 s of CFR.
Do not change the settings.
155 D619