Retro Vintage Connectors 12 pins

ISA 8-Bit Slot 62-Pin

ISA (Industry Standard Architecture) 8-bit expansion slot used in IBM PC and XT clones from 1981, providing an 8-bit data bus and 20-bit address bus for expansion cards at 4.77 MHz.

// connector diagram 12 pins

// loading diagram...

// Specifications

Standard

IBM ISA 8-bit 1981

Pin Count

Data Bus

8-bit

Address Bus

20-bit

Clock

4.77 MHz to 8 MHz

Status

Obsolete embedded industrial use only

// Pin Reference Table

Pin	Name	Function	Type
A1	/IOR	I/O read active low	I/O
A2	/IOW	I/O write active low	I/O
A3	/MEMR	Memory read	I/O
A4	/MEMW	Memory write	I/O
A5	-OCS16	16-bit I/O cycle	I/O
B1	GND	Ground	GND
B2	RESET_DRV	System reset	I/O
B3	+5V	5V power	PWR
B8	IRQ2	Interrupt request 2	I/O
B14	DRQ1	DMA request 1	I/O
B31	D0	Data bus bit 0	I/O
B32	D1	Data bus bit 1	I/O

ISA (Industry Standard Architecture) 8-bit expansion slot used in IBM PC and XT clones from 1981, providing an 8-bit data bus and 20-bit address bus for expansion cards at 4.77 MHz.