Olivetti PF-P09, Service Manual

Page: 302 / 457

Field Service Ver. 1.1 May 2011 15. FAX PROTOCOLS
259
ADJUSTMENT
/ SETTING
15. FAX PROTOCOLS
15.1 G3 ECM (G3 Error Correction Mode)
• G3 ECM is the error correction system newly recommended by consultative committee
of International telephone & telegraph of 1988.
• By G3 ECM, documents are divided into blocks (called partial page) for transmission. If
any error takes place in any frame (one partial page consists of 256 frames at a maxi-
mum) on a partial page, the receiving party generates the retransmit request with errone-
ous frame numbers.
Here is an example where frame 1 and frame 3 are subjected to error:
4139F3C555DA
Transmission Receiving
Error
Note:If one page end and
consists of plural num-
ber of partial pages,
PPS.
NULL signal is trans-
mitted from the trans-
mission side.
Partial page end and end
procedure
Re-transmit request
Re-transmission
Partial page end
Message check
(Received without error)
Partial page
(High-speed modem signal)
300 dps modem signal
Re-transmission for error
(High-speed modem signal)
300 dps modem signal
d-Color MF2400