Ricoh B022, Service Manual, Page: 720 / 878

VIDEO DATA PATH
B418 4-12 SM
First, the FCU stores the incoming data from either an analog line or an ISDN line
to the SAF memory. (The data goes to the FACE at the same time, and is checked
for error lines/frames.)
The FCU then decompresses the data and transfers it to page memory. If image
rotation will be done, the image is rotated in the page memory. The data is
transferred to the IPU.
If the optional G3 unit is installed, the line that the message comes in on depends
on the telephone number dialled by the other party (the optional G3 unit has a
different telephone number from the main fax board).
JBIG Reception
When data compressed with JBIG comes in on PSTN-1 (the standard analog line),
the data is sent to the Function Upgrade Unit for decompression. Then the data is
stored in the page memory, and transferred to the IPU.
When data compressed with JBIG comes in on PSTN-2 (optional extra analog
line), the data is sent to the QM-CODER on the SG3 board for decompression.