Omega Speaker Systems PCI-DAS1001, PCI-DAS1002 manual DIO Port C Data, DIO Control Register

DIO PORT C DATA

BADR3 + 6

PORT C may be configured as an 8-bit port of either input or output, or it may be split into two independent 4-bit ports of input or output. When split into two 4-bit I/O ports, D[3:0]

make up the lower nibble, D[7:4] comprise the upper nibble. Although it may be split, every
write to Port C is a byte operation. Unwanted information must be ANDed out during						reads
and writes must be ORd with current value of the other 4-bit port.
READ/WRITE
7	6	5	4	2	3	1	0
D7	D6	D5	D4	D3	D2	D1	D0

DIO CONTROL REGISTER

BADR3 + 7

The DIO Control register is used configure Ports A,B and C as inputs or outputs. Operation is identical to that of the 8255 in Mode 0.

WRITE

7	6			5			4		2		3		1		0
D7	D6			D5			D4		D3		D2		D1		D0
The following table summarizes the possible I/O Port configurations for the PCI-DAS1000
DIO operatin in MODE 0:
		D4	D3		D1	D0		PORT A		PORT C		PORT B		PORT C
										UPPER				LOWER
		0	0		0	0		OUT		OUT			OUT		OUT
		0	0		0	1		OUT		OUT			OUT		IN
		0	0		1	0		OUT		OUT			IN		OUT
		0	0		1	1		OUT		OUT			IN		IN
		0	1		0	0		OUT			IN		OUT		OUT
		0	1		0	1		OUT			IN		OUT		IN
		0	1		1	0		OUT			IN		IN		OUT
		0	1		1	1		OUT			IN		IN		IN
		1	0		0	0		IN		OUT			OUT		OUT
		1	0		0	1		IN		OUT			OUT		IN
		1	0		1	0		IN		OUT			IN		OUT
		1	0		1	1		IN		OUT			IN		IN
		1	1		0	0		IN			IN		OUT		OUT
		1	1		0	1		IN			IN		OUT		IN
		1	1		1	0		IN			IN		IN		OUT
		1	1		1	1		IN			IN		IN		IN

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