Subversion Repositories Shiroi

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Rev Author Line No. Line
1 nishi 1 
I/O List
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3 
If the I/O port (3n-1) returns 0, card is not there.
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I/O port (3n-1) returns the card type.
6 
	Top 4 bits mean the card genre:
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		0x0: Video
8 
		0x1: Audio
3 nishi 9 
		0x2: System
1 nishi 10 
	Bottom 4 bits mean the card type:
11 
		Video:
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			0x1: Video Mark I
7 nishi 13 
			0x2: Video Mark II
1 nishi 14 
		Audio:
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			0x1: Sound Mark I
3 nishi 16 
		System:
1 nishi 17 
			0x1: Math Mark I
3 nishi 18 
			0x2: Text Mark I
12 nishi 19 
			0x3: Debug
34 nishi 20 
			0x4: ROMcard Mark I
1 nishi 21 
 
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Video Mark I card maps itself to:
29 nishi 23 
	+0: VDP address
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	+1: VDP data
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	+2: See above
1 nishi 26 
 
7 nishi 27 
Video Mark II card maps itself to:
29 nishi 28 
	+0: VDG VRAM address
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	+1: VDG VRAM data
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	+2: See above
7 nishi 31 
 
1 nishi 32 
Sound Mark I card maps itself to:
29 nishi 33 
	+0: PSG address
34 
	+1: PSG data
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	+2: See above
1 nishi 36 
 
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Math Mark I card maps itself to:
29 nishi 38 
	+0: AM9511 stack
39 
	+1: AM9511 command (W) / AM9511 ready (R)
40 
	+2: See above
3 nishi 41 
 
42 
Text Mark I card maps itself to:
29 nishi 43 
	+0: Keyboard data
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	+1: Empty
45 
	+2: See above
12 nishi 46 
 
47 
Debug card maps itself to:
29 nishi 48 
	+0: Address
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	+1: LED
12 nishi 50 
		Bit to 7-segment map:
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		1 2
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		 3
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		4 5
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		 6 7
29 nishi 56 
	+2: See above
34 nishi 57 
 
58 
ROMcard Mark I card maps itself to:
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	+0: Address (Holds 24 bit address inside, gets left shifted by each write)
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	+1: Data
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	+2: See above