User`s manual

44 Wildcat (BL2000)
4.4.2 Digital I/O
Reads the state of an input channel:
IN0–IN10—standard digital inputs, ± 36 V DC
IN11–IN14—pseudo digital inputs using A/D converter inputs ADC0–ADC3, ± 10 V DC
IN15–IN19—pseudo digital inputs using A/D converter inputs ADC4–ADC8, 0 V to 48 V DC
IN20–IN21—pseudo digital inputs using A/D converter inputs DAC0–DAC1, 0 V to 48 V DC
(BL2010 and BL2030)
The threshold is fixed at 2.40 V for channels IN0–IN10. Anything below 2.40 V is a logic 0, and any-
thing higher than or equal to 2.40 V is a logic 1.
The default threshold for channels IN11–IN21 is also set to 2.40 V. The threshold for these channels may
be changed by adding the following two lines to your program.
#undef THRESHOLD
#define THRESHOLD xx.xx
where xx.xx is the desired threshold voltage. Anything below the threshold value is a logic 0, and any-
thing higher than or equal to the threshold value is a logic 1.
PARAMETER
channel is the input channel number (0–21)
RETURN VALUE
The state of the input (0 or 1).
SEE ALSO
brdInit, digOut
Sets the state of a digital output (OUT0–OUT9).
The default setting for the function is for current-sinking outputs. To change from sinking to sourcing
outputs, add the following two lines at the beginning of your program.
#undef OUTPUT_DRIVE
#define OUTPUT_DRIVE SOURCING
The relay is driven by PA0, which is the same Rabbit 2000 parallel port that drives OUT0 and LED DS4.
OUT0 therefore works in parallel with the relay output. Rabbit therefore recommends that you do not use
OUT0 for a digital output when you are using the relay.
PARAMETERS
channel is the output channel number (0–9).
value is the output value (0 or 1).
SEE ALSO
brdInit, digIn
int digIn(int channel);
void digOut(int channel, int value);