分类：
2005-09-07 15:48:51
main contents:
describe the purpose and function of the OpenBoot PROM
upgrade or modify OBP contents with Flash programming
use the OBP test commands available
describe the purpose and function of the non-volatile random-access memory(NVRAM)
define the configuration parameters available in the NVRAM
perform the necessary tasks to alter a defined NVRAM parameter
OpenBoot PROM(OBP) firmware is executed immediately after you turn on your system.the primary tasks of OpenBoot firmware are to:
test and initialize the system hardware
determine the hardware configuration
boot the operating system from either a mass storage device or from a network
provide interactive debugging facilities for testing hardware and software
Features of the OpenBoot firmware include:
1,Plug-in device drivers
2,FCode interpreter:plug-in drivers are written in a machine-independent interpreted language called FCode. each OpenBoot system PROM contains an FCode interpreter. This means
that the same device and driver can be used on machines with different types of CPUs
3,Device tree
4,Programmable user interface
5,Time-Of-Day(TOD) clock
6,Flash programmable
7,The ability to synchronize all Flash PROMs in the system to the same boards types
8,The ability to copy the contents of one I/O boards(slot 3) Flash PROM to another I/O board(slot 9). to do this,type "prom-copy 3 9"
Boot failure due to a corrupted OBP recovery:
These keyboard function reset variable parameters in the NVRAM configuration file
To activate these recovery functions:
1,start with power off
2,press and hold the stop key and action key simultaneously
3,apply power to the system while continuing to hold the keys down until the keyboard LEDs flash
The key combinations and functions available are:
stop-F:Forces I/O to ttya. enter forth command mode on ttya before probing hardware. Use "fexit" to continue probing hardware
stop-N:Resets NVRAM contents to default values
stop-D:Sets the diag-switch? parameter variable to true and enables verbose output druing POST
Use the Flash PROM programming utility to update the OpenBoot PROM on the CPU/Memory board and FCode on the I/O boards
You can reprogram a corrupted PROM if another board of the same type with uncorrupted code is available.
To reprogram a faulty Flash PROM:
1,connect an ASCII terminal to serial port A
2,remove the board with corrupted code from the backplane
3,install a known good board in any available slot
4,turn the keyswitch to the on or diagnostic position
5,wait 15 seconds and press "s" to enter extended POST tests
6,select "f" for fcopy from the extended POST menus
7,insert the board with corrupted code into the backplane
8,select 4 for activate system board and follow the instructions
9,select 1 to copy the code and follow the instructions
10,turn the keyswitch to standby
The NVRAM/TOD chip on the clock board and all I/O boards contain the same information,including the NVRAM environmental variables and configuration settings
Use the ".properties" command to display the CPU/Memory board flash PROM revision in hexadecimal ASCII
Use the ".properties" command to display the I/O board FCode revision in hexadecimal ASCII
ok cd
ok .properties
version 46 43 4f 44 45 20 31 2e 38 2e 33 20 31 39 39 37
model SUNW,525-1432
name flashprom
The OBP user interface is based on an interactive command interpreter that gives you access to an extensive set of functions for hardware and software development, fault isolation, and debugging. A variety of system users, ranging from end-users to system administrators, to system developers, can use these functions
You can enter the OpenBoot environment in the following ways:
shutdown(# init 0)the operating system
execute the stop-A keystroke sequence
press the reset switch on systems equipped with one(this is not recommended)
power-cycle the system(also not recommended)
If your system is configured to not boot automatically, the system stops at the OpenBoot user interface(OK prompt)
After entering the OpenBoot command to probe something,a WARING message is displayed.it informs you that if the operating system has been running, you must type the "reset-all" command before you probe anything. Failure to do this causes the system to hang
The show-devs command displays a listing of all devices currently available in the system.If a device has been added to a disable list but the system has not been reset or gone through a POST, the device still shows up on the dev report. A device can be physically installed in the system chassis but not show up on the following report because it is listed on the disabled-board list. you must remove the entry from the disabled board list after the board has been replaced. You must do a system reset to enable POST and OBP to add the device back to the dev listing
*************************************************************************************************************************************
The correct method for executing OpenBoot probe commands is to reset the system before entering the command. You must type reset-all as the first OBP command,then invoke the desired probe command, as shown:
ok reset-all
ok probe-scsi-all
*************************************************************************************************************************************
OpenBoot Diagnostics(OBDiag) reside in flash PROM on the main logic board. it is available only on the Enterprise 250 and Enterprise 450 at this time
OBDiag can isolate errors on the following system components:
main logic board
diskette drive
CD-ROM drive
tape drive
hard drives
any card installed containing on-board self-test
