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S1571 D1181-001 http://www.tyan.com
Code
Name
Description
C0 Turn Off Chipset Cache
OEM Specific-Cache control
1 Processor Test 1
Processor Status (1FLAGS) Verification.
Tests the following processor status flags:
carry, zero, sign, overflow.
The BIOS sets each flag, verifies they are set,
then turns each flag off and verifies it is off.
2 Processor Test 2
Read/Write/Verify all CPU registers except SS, SP,
and BP with data pattern FF and 00.
3 Initialize Chips
Disable NMI, PIE, AIE, UEI, SQWV.
Disable video, parity checking, DMA.
Reset math coprocessor.
Clear all page registers, CMOS shutdown byte.
Initialize timer 0, 1, and 2, including set EISA timer
to a known state.
Initialize DMA controllers 0 and 1.
Initialize interrupt controllers 0 and 1.
Initialize EISA extended registers.
4 Test Memory Refresh Toggle
RAM must be periodically refreshed to keep the
memory from decaying. This function assures
that the memory refresh function is working
properly.
5 Blank video, Initialize keyboard
Keyboard controller initialization.
6 Reserved
7 Test CMOS Interface and
Verifies CMOS is working correctly, detects bad
Battery Status
battery.
BE Chipset Default Initialization
Program chipset registers with power on BIOS
defaults.
C1 Memory presence test
OEM Specific-Test to size on-board memory.
C5 Early Shadow
OEM Specific-Early Shadow enable for fast boot.
C6 Cache presence test
External cache size detection.
8 Setup low memory
Early chip set initialization.
Memory presence test.
OEM chip set routines.
Clear low 64K of memory.
Test first 64K memory.
6.3 Beep Codes
Currently the only beep code indicates that a video error has occurred and
the BIOS cannot initialize the video screen to display any additional
information. This beep code consists of a single long beep followed by
two short beeps.
6.4 POST Codes
System Resources
