Measurement Computing PCM-DAC02 - Manual (Page 14)

0 to 5V 1 0
0 to 10V 1 1
UDIO & LDIO
Set the direction of the upper and lower four bits of the digital I/O lines. Set to “1”
for output; set to “0” for input. Digital I/O defaults to input on power up
INT_EN
Enable interrupt from pin 5. Enable = “1”. Disable = “0”
EXT_INT
Set to “1” when an interrupt has been detected on pin 5. Interrupt is level only.
Interrupt occurs at TTL high (2.5V < TTL High < 5V). Reading base+0 clears this bit.
10