Appendix A: BIOS POST Codes
Table A-3. Boot Block Flash ROM Terminal POST Errors (Continued)
Post Code | Description |
F2h | Initialize video |
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F3h | Initialize System Management Manager |
F4h | Output one beep |
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F5h | Clear Huge Segment |
F6h | Boot to Mini DOS |
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F7h | Boot to Full DOS |
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If the BIOS detects error 2C, 2E, or 30 (base 512K RAM error), it displays an additional word-bitmap (xxxx) indicating the address line or bits that failed. For example, “2C 0002” means address line 1 (bit one set) has failed. “2E 1020" means data bits 12 and 5 (bits 12 and 5 set) have failed in the lower 16 bits. The BIOS also sends the bitmap to the port-80 LED display. It first displays the checkpoint code, followed by a delay, the high-order byte, another delay, and then the low order byte of the error. It repeats this sequence continuously.
