HP Vectra VE4 Reference Manual page 42

Timer 0/Timer 2
DMA Subsystem
Interrupt Controller
Real-Time Clock
Memory Tests
Test
RAM Address Line
Independence
Size Extended
Memory
Real-Mode
Memory
(First 640 KB)
Shadow RAM
Protected Mode
RAM (Extended
RAM)
Keyboard and Mouse Tests
Test
Keyboard
Mouse
Flexible Disk Drive A Tests
Test
Vectra 4E/xx Technical Reference
Tests Timer 0 and Timer 2. Test failure causes an error code to
be displayed.
Checks the DMA controller registers. Test failure causes an error
code to be displayed.
Tests the Interrupt masks, the master controller interrupt path (by
forcing an IRQ0), and the industry-standard slave controller (by
forcing an IRQ8). Test failure causes an error code to be
displayed.
Checks the real-time clock registers and performs a test that
ensures that the clock is running. Test failure causes an error
code to be displayed.
Purpose
Verifies the address independence of real-mode RAM (no
address lines stuck together). Test failure causes an error code to
be displayed.
Sizes and clears the protected mode (extended) memory and
writes the value into CMOS bytes 30h and 31h. If the system fails
to switch to protected mode, an error code is displayed.
Read/write test on real-mode RAM. (This test is not done during a
reset using [CTRL] [ALT] and [DELETE]). The test checks
each block of system RAM to determine how much is present.
Test failure of a 64 KB block of memory causes an error code to
be displayed, and the test is stopped.
Tests shadow RAM in 64 KB segments (except for segments
beginning at A000h, B000h, and F000h). If they are not being
used, segments C000h, D000h and E000h are tested. Test failure
causes an error code to be displayed.
Tests protected RAM in 64 KB segments (above 1 MB). (This test
is not done during a reset using [CTRL] [ALT] and [DELETE]).
Test failure causes an error code to be displayed.
Purpose
Invokes a built-in keyboard self-test of the keyboard's
microprocessor and tests for the presence of a keyboard and for
stuck keyboard keys. Test failure causes an error code to be
displayed.
If a mouse is present, invokes a built-in mouse self-test of the
mouse's microprocessor and for stuck mouse buttons. Test
failure causes an error code to be displayed.
Purpose
4 System Hardware Tests 42