Specifications

Code(hex) Name Description
1E Reserved
1F Re-initial KB Load keyboard matrix
20 Reserved
21 HPM init Init Heuristic Power Management (HPM)
22 Reserved
23 Program chipset Early Programming of chipset registers
24 Init PNP Init PNP
25 Shadow VBIOS Shadow system/video BIOS
26 Clock Gen Init onboard clock generator and sensor
27 Setup BDA Setup BIOS DATA AREA (BDA)
28 Reserved
29 CPU Speed detect Chipset programming and CPU Speed detect
2A Reserved
2B Init video Initialize Video
2C Reserved
2D Video memory test Test Video Memory and display Logos
2E Reserved
2F Reserved
30 Reserved
31 Reserved
32 Reserved
33 Early keyboard reset Early Keyboard Reset
34 Reserved
35 Test DMA Controller
0
Test DMA channel 0
36 Reserved
37 Test DMA Controller
1
Test DMA channel 1
38 Reserved
39 Test DMA Page
Registers
Test DMA Page Registers
3A Reserved
3B Reserved
3C Test Timer Test 8254 Timer 0 Counter 2.
3D Reserved
3E Test 8259-1 Mask Verify 8259 Channel 1 masked interrupts by
alternately turning off and on the interrupt lines.
3F Reserved
40 Test 8259-2 Mask Verify 8259 Channel 2 masked interrupts by
alternately turning off and on the interrupt lines.
41 Reserved
42 Reserved
43 Test Stuck Interrupt Turn off interrupts then verify no 8259's Interrupt
mask register is on. Test 8259 Force an interrupt
and verify the interrupt occurred.
44 Reserved