User`s guide

44  Operation Theorem
4.4 Digital Input and Output
The ACL-8316/12 provides 16 digital input and 16 digital output channels
through the connector CN1 and CN2 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.
Di
g
ital Out
p
ut
Di
g
ital GND
Di
g
ital
From TTL Signal
To TTL Devices
ACL-8112
Outside Device
74LS244
74LS373
Figure 4.4 Digital I/O Connection
The D/A of ACL-8316 is an optional module, users can purchase it according
to the requirement of the applications. The D/A output range of the ACL-
8316 is fixed bipolar -10V ~ +10V. It can cover both unipolar and bipolar
applications.
To program digital I/O operation is fairly straight forward. 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. The digital I/O
registers
‘ format are shown in section 3.9. 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.