
Troubleshooting
Boot ROM Selftests
4-5
Hardware Initialization Support
Some hardware, such as video circuit initialization and floating RAM positioning, which
can not wait for a system to be booted, must be initialized at power-up as soon as possible
to prevent improper operation.
Go/No-Go Selftest Support
The primary objective is to tell the user that the board computer can boot the operating
system. This consists of indicating which devices are present and reporting all detectable
failures. Boot ROM Selftests are by no means guaranteed to handle all hardware failures
correctly. Several things contribute to this, including current hardware design, limited
code space and the fact that testing for unknown or unexperienced failures is virtually
impossible.
Failure Indications
As the Selftest progresses, the LEDs display the current state. At the end of the test, a
power-up with no errors is indicated by the green LED turned on and blinking and by
immediate entry into the boot scanner.
If a failure occurred during the Selftests, then that failure will be indicated on the LEDs at
the end of the tests. If there was more than one failure, the highest priority failure will be
indicated on the LEDs. All the LED values are listed in Table 4-1.
The power-up Selftest runs automatically when the board computer is powered up. It calls
a series of modules which test various parts of the board computer. The test modules run
are:
Early Selftest
Read/Write Memory Test
Read-only Memory Test
Late Selftest
If an error occurs, an error code is displayed and execution halts. The following sections
provide a description of the failure indications:
Summary of Contents for 9000 Series 743
Page 6: ...Electrostatic Discharge ESD Precautions vi ...
Page 17: ...1 1 1 Product Information ...
Page 31: ...2 1 2 Functional Description ...
Page 58: ...Functional Description Power Distribution 2 28 Figure 2 9 Power Distribution Diagram ...
Page 59: ...3 1 3 Configuration ...
Page 91: ...4 1 4 Troubleshooting ...
Page 125: ...5 1 5 Field Replaceable Units ...
Page 159: ...6 1 6 Reference Documentation ...