PCI ISA busz

ISA=Industry Standard Architecture

A1	/I/O CH CK I/O	channel check; active low=parity error
A2	D7	Data bit 7
A3	D6	Data bit 6
A4	D5	Data bit 5
A5	D4	Data bit 4
A6	D3	Data bit 3
A7	D2	Data bit 2
A8	D1	Data bit 1
A9	D0	Data bit 0
A10	I/O CH RDY I/O	Channel ready, pulled low to lengthen memory cycles
A11	AEN	Address enable; active high when DMA controls bus
A12	A19	Address bit 19
A13	A18	Address bit 18
A14	A17	Address bit 17
A15	A16	Address bit 16
A16	A15	Address bit 15
A17	A14	Address bit 14
A18	A13	Address bit 13
A19	A12	Address bit 12
A20	A11	Address bit 11
A21	A10	Address bit 10
A22	A9	Address bit 9
A23	A8	Address bit 8
A24	A7	Address bit 7
A25	A6	Address bit 6
A26	A5	Address bit 5
A27	A4	Address bit 4
A28	A3	Address bit 3
A29	A2	Address bit 2
A30	A1	Address bit 1
A31	A0	Address bit 0

B1	GND	Ground
B2	RESET	Active high to reset or initialize system logic
B3	+5V	+5 VDC
B4	IRQ2	Interrupt Request 2
B5	-5 VDC	-5 VDC
B6	DRQ2	DMA Request 2
B7	-12 VDC	-12 VDC
B8	/NOWS	No WaitState
B9	+12 VDC	+12 VDC
B10	GND	Ground
B11	/SMEMW	System Memory Write
B12	/SMEMR	System Memory Read
B13	/IOW	I/O Write
B14	/IOR	I/O Read
B15	/DACK3	DMA Acknowledge 3
B16	DRQ3	DMA Request 3
B17	/DACK1	DMA Acknowledge 1
B18	DRQ1	DMA Request 1
B19	/REFRESH	Refresh
B20	CLOCK	System Clock (67 ns, 8-8.33 MHz, 50% duty cycle)
B21	IRQ7	Interrupt Request 7
B22	IRQ6	Interrupt Request 6
B23	IRQ5	Interrupt Request 5
B24	IRQ4	Interrupt Request 4
B25	IRQ3	Interrupt Request 3
B26	/DACK2	DMA Acknowledge 2
B27	T/C	Terminal count; pulses high when DMA term. count reached
B28	ALE	Address Latch Enable
B29	+5 V	+5 VDC
B30	OSC	High-speed Clock (70 ns, 14.31818 MHz, 50% duty cycle)
B31	GND	Ground

C1	SBHE	System bus high enable (data available on SD8-15)
C2	LA23	Address bit 23
C3	LA22	Address bit 22
C4	LA21	Address bit 21
C5	LA20	Address bit 20
C6	LA18	Address bit 19
C7	LA17	Address bit 18
C8	LA16	Address bit 17
C9	/MEMR	Memory Read (Active on all memory read cycles)
C10	/MEMW	Memory Write (Active on all memory write cycles)
C11	SD08	Data bit 8
C12	SD09	Data bit 9
C13	SD10	Data bit 10
C14	SD11	Data bit 11
C15	SD12	Data bit 12
C16	SD13	Data bit 13
C17	SD14	Data bit 14
C18	SD15	Data bit 15

D1	/MEMCS16	Memory 16-bit chip select (1 wait, 16-bit memory cycle)
D2	/IOCS16	I/O 16-bit chip select (1 wait, 16-bit I/O cycle)
D3	IRQ10	Interrupt Request 10
D4	IRQ11	Interrupt Request 11
D5	IRQ12	Interrupt Request 12
D6	IRQ15	Interrupt Request 15
D7	IRQ14	Interrupt Request 14
D8	/DACK0	DMA Acknowledge 0
D9	DRQ0	DMA Request 0
D10	/DACK5	DMA Acknowledge 5
D11	DRQ5	DMA Request 5
D12	/DACK6	DMA Acknowledge 6
D13	DRQ6	DMA Request 6
D14	/DACK7	DMA Acknowledge 7
D15	DRQ7	DMA Request 7
D16	+5 V
D17	/MASTER	Used with DRQ to gain control of system
D18	GND	Ground