Arche Legacy BIOS Post Codes

01	Disable the NMI and test CPU registers
02	Verify the BIOS ROM checksum (32KB at F8000h)
03	Initialize the keyboard controller and CMOS RAM communication
04	Disable the DMA and PIT; test the CMOS RAM interrupt
05	Reset the video controller
06	Test the 8254 programmable interrupt timer
07	Test delta count timer channel 2 (speaker)
08	Test delta count timer channel 1 (memory refresh)
09	Test delta count timer channel 0 (system timer)
0A	Test parity circuit and turn on refresh
0B	Enable parity check and test system timer
0C	Test refresh trace link toggle
0D	Test refresh timing synchronization
10	Disable cache and shadow memory; test the 64KB base memory
11	Perform 64KB memory read/write test
12	Initialize interrupt vector table in lower 1KB of RAM
14	Test CMOS RAM shutdown register...disable DMA and interrupt controllers
15	Test CMOS RAM battery and checksum
16	Test for floppy drive, based on CMOS setup...initialize monochrome video
17	Initialize CGA video
18	Clear the parity status (if any)
19	Test for EGA/VGA video BIOS at C0000h and pass control
1A	Return from video ROM
1B	Test primary video adapter...test video memory
1C	Test secondary video adapter...test video memory
1D	Compare CMOS settings to video adapter
1E	Set video mode according to CMOS settings
20	Display CMOS RAM read/write errors and halt
21	Set cursor and call interrupt 10 to display status message
22	Display power on message; "386 BIOS"; check if CPU speed is 25Mhz or 33Mhz
23	Read new cursor position
24	Display AMI copyright message at the bottom of the screen
25	Test shadow RAM
F0	Shadow RAM test failed
30	Ready to enter protected mode
31	Enter protected mode (A20 gate) and enable timer interrupt (IRQ 0)
32	Get memory size above 1MB
33	Get memory size below 640KB
34	Test memory above 1MB
35	Test memory below 1MB
37	Clear memory below 1MB
38	Clear memory above 1MB
39	Use CMOS shutdown byte and return to real mode
3A	Test 64KB read/write
3B	Test RAM below 1MB and show the area being tested
3C	Test RAM above 1MB and show the area being tested
3D	RAM test complete OK
3E	Ready to return to real mode
3F	Back in real mode
40	Disable A20 gate
41	Check for AMI copyright message in ROM
42	Display the AMI copyright message, if found
43	Test cache memory; Clear <Esc> message
4E	Process shutdown 1; Return to real mode
4F	Restore interrupt vectors and data in BIOS RAM area
50	Test DMA controller
51	Initialize DMA controller
52	Test the DMA controller with patterns
54	Test DMA controller latches
55	Initialize and enable DMA controllers 1 and 2
56	Initialize 8259 programmable interrupt controllers
57	Test 8259 programmable interrupt controllers and setup interrupt mask registers
61	Check DDNIL status bit and display message
70	Perform keyboard (BAT) basic assurance test
71	Program keyboard to AT type
72	Disable keyboard and initialize keyboard circular buffer
73	Display message and initialize floppy controller and drive
74	Attempt to access the floppy drive
75	If the CMOS RAM is good, check and initialize the hard disk controller and drive
76	Attempt to access the hard disk drive
77	Shuffle and internal error codes
79	Check CMOS RAM battery and checksum...clear parity status
7A	Compare size of base/extended memory to CMOS information
7B	Unknown AMI function
7C	Display AMI copyright
7D	Set AT memory expansion bit
7E	Verify the ROM contains and AMI copyright
7F	Clear the <Del> message from the display...check if <Del> was pressed
80	Locate option ROM at C800h to DE00h and pass control to any found
81	Return from option ROM and initialize timer and data area
82	Setup parallel and serial ports
83	Test for math coprocessor
84	Check if keyboard is locked
85	Display any soft error messages
86	Test for option ROM at E0000h
A0	Error found in 256KB or 1MB RAM IC in lower 640KB
A1	Base 64KB random access and data pattern test (only in 386APR and Presto 386SX BIOS)
A9	Initialize on board VGA controller (Presto 386SX BIOS)
B0	Error in 256KB RAM IC in 640KB
B1	Base 64KB random access and data pattern test (only in Presto 386SX BIOS)
E0	Return to real mode and initialize base 64KB RAM (Presto)
E1	Initialize 640KB RAM (Presto)
EF	Configuration memory error - can't find memory
F0	Test shadow RAM from 04000h
00	Call the interrupt 19 boot loader

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