Ricoh D025 Service Manual page 1447

Bit Switches
1: Enabled
ECM frame size
3 0: 256 bytes
1: 64 bytes
CTC transmission conditions
0: After one PPR signal
4 received
1: After four PPR signals
received (ITU-T standard)
Modem rate used for the next
page after receiving a negative
5
code (RTN or PIN)
0: No change 1: Fallback
6
Not Used
Select detection of reverse
polarity in ringing
7
0: Off
1: On
D393
Do not set to 0 unless the line condition is always
bad enough to slow down the data rate to 14.4
kbps or lower.
Keep this bit at "0" in most cases.
0: When using ECM in non-standard (NSF/NSS)
mode, the machine sends a CTC to drop back the
modem rate after receiving a PPR, if the following
condition is met in communications at 14.4, 12.0,
9.6, and 7.2 kbps.
NTransmit- Number of transmitted frames
NResend- Number of frames to be retransmitted
1: When using ECM, the machine sends a CTC to
drop back the modem rate after receiving four
PPRs.
PPR, CTC: These are ECM protocol signals.
This bit is not effective in V.34 communications.
1: The machine's tx modem rate will fall back
before sending the next page if a negative code is
received. This bit is ignored if ECM is being used.
Do not change the settings
This switch is used to prevent reverse polarity in
ringing on the phone line (applied to PSTN-G3
ringing). Do not change this setting
0: No detection Outside Japan
1: Detection Inside Japan only
106 SM