Bitfields for feature byte 1 |
| Bit | Description |
|---|---|
|
7 |
DMA channel 3 used by hard disk BIOS |
|
6 |
2nd interrupt controller (8259) installed |
|
5 |
Real-Time Clock installed |
|
4 |
INT 15/AH=4Fh called upon INT 09h |
|
3 |
wait for external event (INT 15/AH=41h) supported |
|
2 |
extended BIOS area allocated (usually at top of RAM) |
|
1 |
bus is Micro Channel instead of ISA |
|
0 |
system has dual bus (Micro Channel + ISA) |
|
See Also: |