Canon MultiPASS C755, Service Manual, Page: 50 / 143

2-23
MultiPASS C755 Chapter 2: Assembly and Disassembly
REFERENCE
Disassembly 22. ROM replacement
With this unit, there should be no need to replace ROMs, but in the event that ROM replacement becomes
necessary, follow the procedure described below.
a) Caution
After replacing the ROM, you will need to perform an All Clear, so be sure to make a note of any
necessary data beforehand.
a-1) Image data stored in the image memory
Image data stored in the image memory will be wiped clean as soon as the power is cut.
Output all images from the memory before turning off the power.
a-2) User reports
After pressing the
Function
button, press the
Report
button and then use the buttons to select
the reports to be output.
a-3) Service reports
After selecting service data mode, press the Report button and then use the buttons to select the
reports to be output.
b) ROM replacement procedure
(1) Remove power cord.
(2) Put on a wrist-strap and take any other available anti-static precautions.
(3) Perform Disassembly 1.
(4) Use the ROM removal tool to remove the ROM from the SCNT board and PCNT board. Be sure to
check which ROM goes back to which board.
(5) Match up the new ROM and the notch in the IC socket, and insert the new ROM. Make sure that
you are putting the right ROM into the right board.
(6) Replace all covers.
c) Cautions after replacement
(1) If replacing a ROM because of defective ROM elements, finish assembling the machine and then
turn the power on.
(2) If replacing a ROM for the purposes of upgrading because of changes to soft switches, such as
service data or user data, etc., you must perform an All Clear operation. This is because the memory
backed up by the battery still contains the previous settings. Before performing All Clear, print out
the data backed up by the battery, in case you need to re-programme them.
Refer to page 3-6, 3.1 CS LED Light-on Duration Adjustment, for details.