Measurement Computing CIO-DAS08-AOH - Manual (Page 15)

6.3 STATUS AND CONTROL REGISTER
BASE ADDRESS + 2 (Read / Write) Read Functions
MUX0 MUX1 MUX2 IRQ IP1 IP2 IP3 EOC
0 1 2 3 4 5 6 7
READ = STATUS
EOC = 1 the A/D is busy converting and data should not be read.
EOC = 0 the A/D is not busy and data may be read.
IP3 to IP1 are the digital input lines on the 37-pin analog connector.
IRQ is the status of an edge triggered latch connected to pin 24 of the analog connector. It is high (1) when a positive edge
has been detected. It may be reset to 0 by writing to the INTE mask at BASE + 2 write.
MUX 2 to MUX 0 is the current multiplexer channel. The current channel is a binary coded number between 0 and 7 .
WRITE = CONTROL
BASE + 2 (Read / Write) Write Functions
MUX0 MUX1 MUX2 INTE OP1 OP2 OP3 OP4
0 1 2 3 4 5 6 7
OP4 to OP1 are the digital output lines on the 37-pin analog connector.
INTE = 1 enables interrupts (positive edge triggered) onto the PC bus IRQ selected via the IRQ jumper on the
CIO-DAS08-AOx.
INTE = 0 disables the passing of the interrupt detected at pin 24 to the PC bus.
IRQ is set to 1 every time an interrupt occurs. If you want to process successive interrupts then set INTE = 1 as the last step
in your interrupt service routine.
MUX2 to MUX0. Set the current channel address by writing a binary coded number between 0 and 7 to these three bits.
NOTE
Every write to this register sets the current A/D channel MUX setting to the number in bits 2-0.
6.4 PROGRAMMABLE GAIN REGISTER
BASE ADDRESS + 3
A software-programmable register controls the input amplifier. It allows you to select unipolar/bipolar ranges and gains of 1,
10, 100 or 1000 (...AOH) or 1, 2, 4 or 8 (...AOL) via software command.
The register is addressed at the board's Base Address + 3. This register is unused on the CIO-DAS08 and so represents no
conflict with existing CIO-DAS08 software.
To set the input range of the CIO-DAS08-AOx board, select the desired range from the table and write the code in decimal or
hexadecimal to base address +3. Here is an example in BASIC:
100 OUT &H303, 6 'Set gain = 1000, +/-0.005V range.
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