Canon iR3570 Series, Service Manual

Page: 169 / 722

Chapter 4
4-11
4.3.2 Start-Up Sequence
0006-6703
iR2270 / iR2870 / iR3570 / iR4570 / / iR2270N / / iR2870N / / iR3570N / / iR4570N / iR2230 / / / iR3530 /
<Boot ROM Area>
-Self Diagnosis Program (interval 1)
The self-diagnosis program is run by the CPU on the main controller PCB when the main power switch is turned on.
The program is used to check the condition of the image memory (SDRAM) and the HDD.
The machine will indicate an error code if it finds a fault while running the program.
-Boot Program (interval 2)
When the self-diagnosis program ends normally, the CPU on the main controller PCB executes the boot program.
The program is used to read the system software from the HDD to write it into the image memory (SDRAM).
<Image Memory (SDRAM) Area> (interval 3)
The system software written by the boot program initializes the various functional blocks (e.g., I/F settings of the main controller).
When all the foregoing ends normally, the machine becomes ready to accept a job
(i.e., the control panel shows the Operation screen, and the LED on the Start key changes from red to green).
F-4-12
F-4-13
1
Progress bar
3
2
Image memory (SDRAM)
CPU
HDD
System
area
Image data
area
BootROM
Self diagnosis
program
Boot
program
: access to the program during execution
: access for checking
Main controller PCB
- While the Self-Diagnosis Program Is Being Executed