ADLINK PCM-9112+ - Manual (Page 48)

40 • Operation Theory
4.4 Digital Input and Output
The PCI-9112 provides 16 digital input and 16 digital output channels through
the connectors CN1 and CN2 on-board. The digital I/O signal is fully
TTL/DTL compatible. The digital I/O signals are illustrated in Figure 4.4 .
To program the digital I/O operation is fairly straightforward. The digital input
operation is used to read data from corresponding registers, and the digital
output operation is to write data to the corresponding registers. The digital I/O
registers structure is shown in section 3.7. Note that the DIO data channel
can only be read or written to in groups of 16 bits. It is impossible to access
individual bit.
Digital Output (DO)
Digital GND (DGND)
Digital Input(DI)
From TTL Signal
To TTL Devices
9112 Series Outside Device
74LS244
74LS373
Figure 4.4 Digital I/O Connection