32
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Operation Theorem
4.3 Digital Input and Output
The ACL-8111 provides 16 digital input and 16 digital output channels
through the connector CN2 and CN3 on board. The digital I/O signal are fully
TTL/DTL compatible. The detailed digital I/O signal specification can be
referred in section 1.3.
Digital Output (DO)
Digital GND (DGND)
Digital Input(DI)
From TTL Signal
To TTL Devices
ACL-8111
Outside Device
74LS244
74LS373
Figure 4.3 Digital I/O Connection
To program digital I/O operation is fairly straightforward. The digital input
operation is just to read data from the corresponding registers, and the digital
output operation is to write data to the corresponding registers. Note that the
DIO data channel can only be read or written in form of 8 bits together. It is
impossible to access individual bit channel.