HP LaserJet Enterprise 500 Maintenance Manual - Page 96

Finish programming FLASH

Page 96 highlights

Chapter 4 The Power On Sequence • Check for Pedestal - Boot code uses the control panel to determine if the printer is a pedestal or floor cabinet model. Boot code needs to know the difference so the exhaust fan fault can be disabled on a pedestal model. "FAN DISABLED" is printed out at the debug serial port of a pedestal model. • Check for Download Mode - Boot code checks whether the ON LINE and FF keys were pressed at power up. If so, the printer enters download mode. If not, the printer continues the boot routines. • Check for Diagnostics Mode - Boot code checks whether the ; (PREV) and > (DOWN) keys were pressed at power-up. If so, the printer enters the Boot Diagnostics menu. If not, the printer continues the boot routines. • Check for Remote Download Mode - Boot code checks if the user remotely requested the printer to enter download mode. If so, the printer enters download mode. If not, the printer continues boot routines. • Check for Flash Optimize - Boot code checks if the user requested the flash file system to be optimized at power up. If so, flash memory is optimized at this time. If not, the printer continues boot routines. • Check EC Program - The EC calculates a checksum of the program stored in its flash memory. If there is problem with its program, the EC puts the message "nopg" in the ECDC communications register. If the boot code detects this message, it displays "ERROR: EC PROGRAM NOT VALID" on the LCD. If the EC processor does not respond within three seconds, the boot code sends "EC STOPPED AT STATE XXXX" to the LCD, where XXXX is one of these states: State 0000 0001 0002 0003 0004 0005 0006 0007 0008 0009 000A Description Power up Enter checksum calculation Enter copy download code from FLASH into shared DRAM Enter programming FLASH mode Erase EC FLASH Program FLASH Finish programming FLASH Enter initialization of EC serial debug Enter EC firmware task initializations Enter power up coil diagnostic Start running normal EC firmware • Check Security PAL and NVRAM - The chip select for NVRAM comes from the security PAL. If the PAL is not installed, NVRAM cannot be accessed, so the PAL is tested before NVRAM. If the security PAL is not 96

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96
Chapter
4
The Power On Sequence
Check for Pedestal
— Boot code uses the control panel to determine if
the printer is a pedestal or floor cabinet model. Boot code needs to know
the difference so the exhaust fan fault can be disabled on a pedestal
model. “FAN DISABLED” is printed out at the debug serial port of a
pedestal model.
Check for Download Mode
— Boot code checks whether the ON LINE
and FF keys were pressed at power up. If so, the printer enters download
mode. If not, the printer continues the boot routines.
Check for Diagnostics Mode
— Boot code checks whether the
;
(PREV)
and
>
(DOWN)
keys were pressed at power-up. If so, the
printer enters the Boot Diagnostics menu. If not, the printer continues the
boot routines.
Check for Remote Download Mode
— Boot code checks if the user
remotely requested the printer to enter download mode. If so, the printer
enters download mode. If not, the printer continues boot routines.
Check for Flash Optimize
— Boot code checks if the user requested the
flash file system to be optimized at power up. If so, flash memory is
optimized at this time. If not, the printer continues boot routines.
Check EC Program
— The EC calculates a checksum of the program
stored in its flash memory. If there is problem with its program, the EC
puts the message “nopg” in the ECDC communications register. If the
boot code detects this message, it displays “ERROR: EC PROGRAM
NOT VALID” on the LCD. If the EC processor does not respond within
three seconds, the boot code sends “EC STOPPED AT STATE XXXX” to
the LCD, where XXXX is one of these states:
Check Security PAL and NVRAM
— The chip select for NVRAM comes
from the security PAL. If the PAL is not installed, NVRAM cannot be
accessed, so the PAL is tested before NVRAM. If the security PAL is not
State
Description
0000
Power up
0001
Enter checksum calculation
0002
Enter copy download code from FLASH into shared DRAM
0003
Enter programming FLASH mode
0004
Erase EC FLASH
0005
Program FLASH
0006
Finish programming FLASH
0007
Enter initialization of EC serial debug
0008
Enter EC firmware task initializations
0009
Enter power up coil diagnostic
000A
Start running normal EC firmware