W1, W2: Undocumented

W3: BIOS ROM

Jumper to Enable the BIOS.

Open to Disable the BIOS.

W4: Address Select

(1/2): 324h.

(2/3): 320h.

W5: ROM BIOS Size

(1/2): 32/64KB.

(2/3): 16KB.

W6: Reduced Write Current Head Select

(1/2): 16 Heads.

(2/3): 8 Heads.

W7: Interrupt Select

(1/2): IRQ#5.

(2/3): IRQ#2.

W8: Undocumented (Default is 2/3).

W9: C023 Setting: (Default is 1/2).

W10: Feature Select

(1/2): Undocumented Special Feature.

(2/3): Default.

SW1 Jumper Block Description. (For Rev. G BIOS)

BIOS TABLE	Formatted Capacity	Drive 1		Drive 0		Drive Type	# of Heads	# of Cyls.	Pre- Comp	RWC Cyl.
		#1	#2	#3	#4
3	10MB	Off	Off	Off	Off	ST412	4	306	0	N/A
2	20MB	On	Off	On	Off	ST225	4	612	128	N/A
1	10MB	Off	On	Off	On	MS3012	2	612	128	128
0	20MB	On	On	On	On	HH-725	4	612	N/A	N/A

SW1 Jumper Block Descriptions for Rev. H BIOS

BIOS Table	Size	Drive 1			Drive 0			Drive Type	# of Heads	# of Cyls.	Pre- Comp	RWC Cyl.
		#1	#2	#7	#3	#4	#8
0	42.5MB	On	On	On	On	On	On	ST4051	5	977	N/A	N/A
1	31.9MB	Off	On	On	Off	On	On	ST4038	5	733	300	N/A
2	33.4MB	On	Off	On	On	Off	On	RO-203E	6	640	N/A	N/A
3	62.3MB	Off	Off	On	Off	Off	On		8	1024	N/A	N/A
4	42.8MB	On	On	Off	On	On	Off	ST251	6	820	N/A	N/A
5	10.0MB	Off	On	Off	Off	On	Off	MS3012	2	612	128	128
6	20.0MB	On	Off	Off	On	Off	Off	ST225	4	612	128	N/A
7	10.0MB	Off	Off	Off	Off	Off	Off	ST412	4	306	0	N/A

Switch 1 (SW1)

SW1(5): Interrupt Selection

On: IRQ#5.

Off: IRQ#2.