Compsee Apex III, Technical Reference Manual

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Apex PDT Technical Reference Manual 4 BIOS
COAM30002 Rev. 2.00 8/13/02
4-9
POST Errors
When an error occurs during the Power-On Self Test (POST)
sequence, the PhoenixPICO

BIOS will display an error message
describing the problem. In addition, a Beep Code (one long tone
followed by two short tones) will occur during the POST sequence
if the video configuration fails or if any ROM module does not
checksum to zero.
External ROM modules if installed, can also issue an audible tone
alert (one long tone followed by a series of short tones).
Terminal POST Errors
There are several POST routines that can issue a Terminal POST
error and shutdown the system if they fail. Prior to shutting down
the system, the Terminal Error-Handler performs the following
functions:
q
Issues a beep code signifying the test point error
q
Attempts to initialize the video
q
Writes the error in the upper left hand corner of the screen
The beep code is derived from the test point error as follows:
1.
The 8-bit error code is broken down into four 2-bit groups
(the most significant group is discarded if it is 00).
2. Each group is made one-based (1 through 4) by adding one.
3.
Short beeps are generated for the number in each group.
Example: Test point 01Ah = 00 01 10 10 = 1-2-3-3 beeps
Test Points And Beep Codes
If the BIOS detects a terminal error condition, the POST is halted
after the issuance of the terminal beep code and the BIOS attempts
to display the error code in the upper left-hand corner of the screen.
The BIOS will repeatedly attempt to display the error code on the
screen.
If the system hangs up before the BIOS can process the error, the
screen will not display the error code.
The following tables display the beep codes and test point
information pertaining to the Apex PDT PhoenixPICO

BIOS.