Interface pinouts and interrupts
PS/2 keyboard port
1
4
2
3
5
6
Pin Signal
1 Data
2 not
used
3
0 V
4
+5 V
5 Clock
6 not
used
Serial interface
1
5
6
9
Pin
Signal
Meaning
1
DCD
Data Carrier Detect
2
RxD
Receive
Data
3
TxD
Transmit
Data
4
DTR
Data Terminal Ready
5
Signal
Ground
Ground
6
DSR
Data Set Ready
7
RTS
Request to Send
8
CTS
Clear to Send
9
Ri
Ring
Indicator
A26361-D824-Z120-5-7619
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Interface pinouts and interrupts
Interrupt Request Levels and DMA channels
Interrupt Request Levels and DMA channels are listed below.
Interrupt Request Levels
IRQ0 = timer 0
IRQ1 = keyboard
IRQ2 = free or IRQ9
IRQ3 = serial interface 2 (COM2/COM4)
IRQ4 = serial interface 1 (COM1/COM3)
IRQ5 = free
IRQ6 = floppy disk controller
IRQ7 = parallel interface (LPT1/LPT3)
IRQ8 = real-time clock interrupt
IRQ9 = VGA controller or free
IRQ10 = free
IRQ11 = free
IRQ12 = mouse
IRQ13 = math coprocessor
IRQ14 = IDE hard disk controller
IRQ15 = free
DMA channels
DMA0 = free
DMA1 = free - normally used by LAN
DMA2 = floppy disk controller
DMA3 = IDE
DMA4 = DMA channel cascading
DMA5 = free
DMA6 = free
DMA7 = free
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A26361-D824-Z120-5-7619
