5
Diagnostics
There are two types of self-tests:
- Kernel Self-Test: A non-interactive test suite that performs the minimum hardware tests required to ensure booting. Kernel Self-Test resides in the boot ROM and executes automatically upon power-up.
- Extended Self-Test: Menu-driven interactive and non-interactive tests intended for use by service personnel. Extended Self-Test is invoked from the boot monitor using the selftest command or downloaded from a remote host, depending on your network computer model.
Kernel Self-Test
Kernel Self-Test runs automatically whenever the network computer is turned on and takes approximately 10 seconds to complete. If Kernel Self-Test runs without detecting a hardware fault, the network computer attempts to boot.
Fault Information
Self-test programs provide status and fault information by displaying codes with LED indicators on the keyboard, by ringing the bell, and by displaying messages on the display. In the event of a fault, if enough hardware is working, Kernel Self-Test continues to its completion, at which time the Boot Monitor takes control. The boot monitor continues to blink a fault code in the keyboard LEDS until the Return key is pressed.
Table 5-2, Table 5-3, and Table 5-4 list the fault codes for FRU's tested by Kernel Self-Test.
Keyboard LED Indicators
The 101- and 102-key keyboards have three adjacent LED indicators in the top right corner. The VT200 keyboard has a fourth indicator (Hold Screen) to the left of the other indicators. Table 5-1 on page 5-3 shows the indicator positions.
Initially, keyboard firmware briefly turns the LEDs on, then off. Shortly after power-up, Kernel Self-Test sequences the LEDs, one at a time, from right to left. All LEDs are then turned on, and Kernel Self-Test tests the standard network computer memory. If no faults are detected, Kernel Self-Test initializes the network computer display and completes the kernel power-up testing.
During the power-up sequence, Kernel Self-Test reports boot status to the keyboard LEDs. Table 5-1 lists the condition of the keyboard LEDs as Kernel Self-Test progresses through the boot process.
For location of the indicators, refer to Appendix B, Keyboards for your specific keyboard.
a = on, x = off
bVT200/LK401, UNIX, and Sun V keyboards onlyPressing any key during Kernel Self-Test instructs the network computer to pass control to the boot monitor when Kernel Self-Test is complete and to display this message:
Boot process interrupted by key press...
Type HELP for a list of commands
BOOT>Pressing any key during the boot process after Kernel Self-Test is complete instructs the logic module to terminate the boot and pass control to the boot monitor. This message appears on the display:
Boot terminated due to key press
Type HELP for a list of commands
BOOT>Self-test programs reveal status and fault information by displaying failure codes with light-emitting diode (LED) indicators on the keyboard, by displaying fault messages on the display, and by ringing the bell.
Table 5-2 lists the faults for FRUs tested by Kernel Self-Test.
Table 5-3 presents the LED Indicator Fault Code Definitions for the NC200 and models; Table 5-4 shows the definitions for NC900 models.
Table 5-3 LED Indicator Fault Code Definitions for NC200 Network Computers= blinking, x = offTable 5-4 LED Indicator Fault Code Definitions for NC900 Network Computers
Hold Screen LED Left LED Middle LED Right LED Faulty FRU Indicated x x x Main logic board x x x Boot ROM x x Option Memory DIMM x x Flash Memory Option x x Keyboard/mouse interface x Option I/O portIf the display malfunctions, you can tell if the boot failed by noting the indicator display. If the bell rings, or both the middle and right indicators turn off together, or if any indicators are blinking, the logic module did not boot successfully and has entered the boot monitor.
No activity on power-up indicates a malfunction in the kernel hardware (Boot ROM, CPU, ASICs, etc.).
Extended Self-Test
The Extended Self-Test consists of a full complement of tests used by service technicians to diagnose hardware related problems.