ADLINK Technology NuDAQ ACL-8216, User Manual

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Registers Format
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D/A reference voltage which set by the JP1,JP2 and JP3. Please
refer section 2.11 for jumper setting. The reference voltage will effect
the output voltage. If the reference voltage is -5V, the D/A output
scaling will be 0~5V. If the reference voltage is -10V, the D/A output
scaling will be 0~10V.
Note that the D/A registers are " double buffered ", so that the D/A
analog output signals will not be updated until the high byte is written.
When write 12 bits data to D/A registers of the ACL-8216, the low
byte must be written before the high byte. This procedure can insure
a single step transition when the D/A conversion.
4.3 Digital Input and Output
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 4.9.
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.
The ACL-8216 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.
Digital Output (DO)
Digital GND (DGND)
Digital Input(DI)
From TTL Signal
To TTL Devices
ACL-8216
Outside Device
74LS244
74LS373
4.4 Timer/Counter Operation