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9.ISA 是 Industry Standard Architecture 的缩写

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引脚
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定义
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方向
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说明
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A1
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/I/O CH CK
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I/O channel check; active low="parity" error
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A2
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D7
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" type="#_x0000_t75">
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Data bit 7
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A3
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D6
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" type="#_x0000_t75">
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Data bit 6
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A4
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D5
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" type="#_x0000_t75">
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Data bit 5
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A5
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D4
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" type="#_x0000_t75">
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Data bit 4
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A6
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D3
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" type="#_x0000_t75">
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Data bit 3
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A7
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D2
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" type="#_x0000_t75">
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Data bit 2
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A8
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D1
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" type="#_x0000_t75">
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Data bit 1
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A9
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D0
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" type="#_x0000_t75">
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Data bit 0
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A10
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I/O CH RDY
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I/O Channel ready, pulled low to lengthen memory cycles
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A11
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AEN
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Address enable; active high when DMA controls bus
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A12
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A19
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Address bit 19
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A13
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A18
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Address bit 18
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A14
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A17
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Address bit 17
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A15
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A16
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Address bit 16
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A16
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A15
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Address bit 15
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A17
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A14
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Address bit 14
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A18
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A13
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Address bit 13
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A19
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A12
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Address bit 12
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A20
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A11
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Address bit 11
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A21
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A10
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Address bit 10
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A22
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A9
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Address bit 9
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A23
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A8
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Address bit 8
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A24
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A7
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Address bit 7
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A25
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A6
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Address bit 6
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A26
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A5
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Address bit 5
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A27
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A4
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Address bit 4
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A28
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A3
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Address bit 3
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A29
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A2
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Address bit 2
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A30
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A1
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Address bit 1
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A31
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A0
|
Address bit 0
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B1
|
GND
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Ground
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B2
|
RESET
|
Active high to reset or initialize system logic
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B3
|
5V
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5 VDC
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B4
|
IRQ2
|
Interrupt Request 2
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B5
|
-5VDC
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-5 VDC
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B6
|
DRQ2
|
DMA Request 2
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B7
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-12VDC
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-12 VDC
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B8
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/NOWS
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No WaitState
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B9
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12VDC
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12 VDC
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B10
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GND
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Ground
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B11
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/SMEMW
|
System Memory Write
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B12
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/SMEMR
|
System Memory Read
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B13
|
/IOW
|
I/O Write
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B14
|
/IOR
|
I/O Read
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B15
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/DACK3
|
DMA Acknowledge 3
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B16
|
DRQ3
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DMA Request 3
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B17
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/DACK1
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DMA Acknowledge 1
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B18
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DRQ1
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DMA Request 1
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B19
|
/REFRESH
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" type="#_x0000_t75">
|
Refresh
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B20
|
CLOCK
|
System Clock (67 ns, 8-8.33 MHz, 50% duty cycle)
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B21
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IRQ7
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Interrupt Request 7
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B22
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IRQ6
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Interrupt Request 6
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B23
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IRQ5
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Interrupt Request 5
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B24
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IRQ4
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Interrupt Request 4
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B25
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IRQ3
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Interrupt Request 3
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B26
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/DACK2
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DMA Acknowledge 2
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B27
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T/C
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Terminal count; pulses high when DMA term. count reached
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B28
|
ALE
|
Address Latch Enable
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B29
|
5V
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5 VDC
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B30
|
OSC
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High-speed Clock (70 ns, 14.31818 MHz, 50% duty cycle)
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B31
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GND
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Ground
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C1
|
SBHE
|
" type="#_x0000_t75">
|
System bus high enable (data available on SD8-15)
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C2
|
LA23
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" type="#_x0000_t75">
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Address bit 23
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C3
|
LA22
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" type="#_x0000_t75">
|
Address bit 22
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C4
|
LA21
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" type="#_x0000_t75">
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Address bit 21
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C5
|
LA20
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" type="#_x0000_t75">
|
Address bit 20
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C6
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LA18
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" type="#_x0000_t75">
|
Address bit 19
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C7
|
LA17
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" type="#_x0000_t75">
|
Address bit 18
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C8
|
LA16
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" type="#_x0000_t75">
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Address bit 17
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C9
|
/MEMR
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" type="#_x0000_t75">
|
Memory Read (Active on all memory read cycles)
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C10
|
/MEMW
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" type="#_x0000_t75">
|
Memory Write (Active on all memory write cycles)
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C11
|
SD08
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" type="#_x0000_t75">
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Data bit 8
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C12
|
SD09
|
" type="#_x0000_t75">
|
Data bit 9
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C13
|
SD10
|
" type="#_x0000_t75">
|
Data bit 10
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C14
|
SD11
|
" type="#_x0000_t75">
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Data bit 11
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C15
|
SD12
|
" type="#_x0000_t75">
|
Data bit 12
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C16
|
SD13
|
" type="#_x0000_t75">
|
Data bit 13
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C17
|
SD14
|
" type="#_x0000_t75">
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Data bit 14
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C18
|
SD15
|
" type="#_x0000_t75">
|
Data bit 15
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D1
|
/MEMCS16
|
Memory 16-bit chip select (1 wait, 16-bit memory cycle)
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D2
|
/IOCS16
|
I/O 16-bit chip select (1 wait, 16-bit I/O cycle)
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D3
|
IRQ10
|
Interrupt Request 10
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D4
|
IRQ11
|
Interrupt Request 11
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D5
|
IRQ12
|
Interrupt Request 12
| |
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D6
|
IRQ15
|
Interrupt Request 15
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D7
|
IRQ14
|
Interrupt Request 14
| |
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D8
|
/DACK0
|
DMA Acknowledge 0
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D9
|
DRQ0
|
DMA Request 0
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D10
|
/DACK5
|
DMA Acknowledge 5
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D11
|
DRQ5
|
DMA Request 5
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D12
|
/DACK6
|
DMA Acknowledge 6
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D13
|
DRQ6
|
DMA Request 6
| |
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D14
|
/DACK7
|
DMA Acknowledge 7
| |
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D15
|
DRQ7
|
DMA Request 7
| |
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D16
|
5 V
|
|
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D17
|
/MASTER
|
Used with DRQ to gain control of system
| |
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D18
|
GND
|
|
Ground
|

本文详细介绍了Industry Standard Architecture (ISA) 总线的引脚定义及其功能,包括地址线、数据线、控制信号等关键部分,并阐述了这些信号在计算机硬件通信中的作用。
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