ABB PGC2000 - READ DIGITAL INPUT Function

2000-OSM, F1 10-29
Comments: channel is the analog to digital converter channel (0 or 1). On the Chroma
Board, channel 0 is read from J106 pins 1 and 2, channel 1 is read from
J106 pins 4 and 5.
NOTE
The Chroma I/O Board must have A/D Converter ICs UG1 and UH1 installed (see
Figure 10-1) in order for this function to operate.
UH1
UG1
Figure 10-1. CHROMA I/O BOARD, SHOWING UG1 AND UH1
Example: For this example, let a temperature sensor register -4096 at -30°C and 4095
at 1000°C.
0010 SLOPE! = (1000.-(-30.))/(4095.-(-4096.))
0020 T_ZERO! = 1000. - SLOPE! * 4095.
0030 TEMPERATURE! = SLOPE! * FLT(
0040 :RAI(0)) + T_ZERO!
Use “T=mx+T0” to compute temperature from the reading of the A/D
converter, where “m” is the slope of the line, “x” is the A/D value, and “T0” is
the temperature at an A/D value of zero.
READ DIGITAL INPUT Function
Description: Returns the status, 0 or 1, of the digital input addressed.
Syntax: RDI(channel%,type%)
Comments: channel% is the input channel (1-96)
type% is the specific input to be sensed:
type: 0, channel: 1-5; input description: sensor alarms (depends on
software configuration)
type: 1, channel: 1-12; input description: remote stream select
type: 2, channel: 1-16; input description: Vista BASIC
type: 3, channel: 0; input description: flame out alarm
type: 4, channel: 0; input description: purge alarm
type: 5, channel: 0; input description: carrier alarm
type: 6, channel: 0; input description: low oven temp alarm
type: 7, channel: 0; input description: high oven temp alarm
type: 8, channel: 0; input description: low calibration sample alarm
type: 9, channel: 0; input description: low sample flow alarm