FIC M296 - Manual (Page 139)

Troubleshooting and Repair
Table 6-3 (c) BIOS Beep Codes
Beep
Code Diagnostic
Code
Description Test Performed
3-3-4 2Bh Screen memory test in
progress or failure. The video buffers (B0000h and B8000h)
are tested with a pattern test and a
rolling ones test. Failure will result in a
beep code but not a system halt.
3-4-1 2Ch Screen initialization in
progress. Until the video installation is confirmed,
any calls to INT 10h Function 0 (set
mode) will be prefaced with the
diagnostic code. There is no expected
failure from this.
3-4-2 2Dh Screen retrace test in
progress or failure. Over a period of time, the retrace bit
(bit0) in the appropriate CRT controller
status register (either port 3BAh or
3DAh) is read and tested. The retrace bit
should toggle from 0 to 1, then 1 to 0
within the time period.
None 2Eh Search for video ROM in
progress.
No specific test is performed by the
system BIOS - just indicates that the
BIOS is about to jump to the initialization
code in the video option ROM.
none 30h Screen running with video
ROM. No specific test is performed - just
indicates that a video option ROM was
found and believed to be operating.
none 31h Monochrome monitor
operable. No specific test is performed - just
indicates that the BIOS believes a
monochrome monitor is installed and is
operating.
none 32h Color monitor (40-column)
operable. No specific test is performed - just
indicates that the BIOS believes a color
monitor is installed and is operating. The
mode has been set to 40-column as
selected by the user in CMOS RAM.
none 33h Color monitor (80-column)
operable. No specific test is performed - just
indicates that the BIOS believes a color
monitor is installed and is operating. The
mode has been set to 80-column as
selected by the user in CMOS RAM.
4-2-1 34h Timer-tick interrupt test in
progress or failure. All interrupts expect the timer-tick
interrupt are masked off at the interrupt
controllers. If a timer-tick interrupt does
not occur during a specific time period,
an error message is displayed on the
screen. The system does not halt.
4-2-2 35h Shutdown test in progress or
failure. A return address is stored in 40:67h and
the processor is reset via the keyboard
controller. If a timer tick occurs during
this time period, an error message is
displayed on the screen. Other failures
are hard to detect. If possible, the BIOS
will continue with POST, skipping the
memory tests.
FIC M295 / M296 Service Manual 6-7