Power On Self Test (Post) - Xerox Phaser 7500 Service Manual

General Troubleshooting

Power On Self Test (POST)

4-4
POST diagnostics provide a quick means of isolating a defective subsystem
associated with the Image Processor Board and SDRAM. There are two kinds of
POST faults: soft and hard. A soft fault is any fault that allows the operating
system to initialize. Soft faults do not stop printer operation and are reported on
the Startup page after the system is running. A hard fault prevents the operating
system from initializing stopping further printer operation. Hard faults are
indicated with blinking LEDs and the failed test appearing on the display.
The following tests execute when the printer is powered on after the Boot Loader
runs, and before the operating system is loaded and initialized. Bypass POST by
pressing the OK button at power on until the splash screen displays.
POST Test Descriptions
Test No. Test Name
1 DDR2 SDRAM
14 Real Time
Clock
3 I/O ASIC
4 Memory
5 Configuration
Chip
10 EEPROM
11 Ethernet
12 CPU Interrupts H: 12
13 USB
14 Real Time
Clock
15 RAM DIMM
Fault Code (Hard, Soft)
H: 1 (Special)
S: 14 (POST_DEV_RTC)
H: 3
H: 4
N/A
H: 10
H: 11 (POST_DEV_ETH)
S: 13 (POST_DEV_USB)
S: 14 (POST_DEV_RTC)
S: 15 (POST_DEV_DIMM)
Phaser 7500 Printer Service Manual
Description
Boot loader tests this.
DDR2 type RAM
Test performed.
No test performed.
No test performed.
No test performed.
This is redundant and
of no additional value.
Postscript is perfectly
capable of alerting the
user to a Configuration
Chip issue.
If Postscript reports a
problem with the
Configuration Chip,
examine the socket for
damage, reseat the
Configuration Chip and
power cycle the printer.
Test performed.
Test performed.
Test performed.
No test performed.
Limited value. The
ability to perform I/O is
what matters to an
end-user. This test never
did any I/O check.
In customer mode,
simply print via USB.
No test performed. No
added value.