Technical Information 1-17
•
NEC port 0C11h
0:
Not used
1:
ECP DMA Select (3 or 1) (R/W)
0
Selects DMA 1
1
Selects DMA 3
2:
ECP Enable (R/W)
0
Disable ECP
1
Enables ECP
3: Parallel Port IRQ Select (R/W)
0
Selects IRQ 5
1
Selects IRQ 7
4: Second Serial Port Enable (R/W)
0
Enables second serial port
1
Disables second serial port
5: Second Serial Port IRQ Select (R/W)
0
Selects IRQ 3
1
Selects IRQ 11
6: First Serial Port Enable (R/W)
0
Enables first serial port
1
Disables first serial port
7: First Serial Port IRQ Select (R/W)
0
Selects IRQ 4
1
Selects IRQ 10
•
NEC port 0C12h
0
1
2
3
4
5
6
7
1st Serial
Port IRQ
Select
1st Serial
Port
Enable
2nd Serial
Port IRQ
Select
Parallel Port
IRQ Select
ECP
Enable
ECP DMA
Select
2nd Serial
Port
Enable
Not
Used