Sensoray 7429 - Manual (Page 30)

Calibrate Board
This command is used to calibrate all 7429 internal standards. All measurements made
by the coprocessor are referenced to these standards. To perform a board calibration,
you must supply two reference voltages (5 volts and 500 millivolts) and one reference
resistance (380 ohms).
References must be calibrated in the following order: 5 volts, 500 mV, and 380 ohms.
COMMAND: (224 + CHAN),(CAL CODE),(DATA HIGH),(DATA LOW)
RESPONSE: (GARBAGE)
Cal Code Reference
0 5 volts
1 500 mV
2 380 ohms
Example: This code segment will assist you in calibrating the 7429.
FOR calCode% = 0 to 2
SELECT CASE calCode%'setup cal parameters
CASE 0
refName$ = "5 volt"
scalar% = 5000
sensorCode% = 0
CASE 1
refName$ = "500 mV"
scalar% = 50
sensorCode% = 13
CASE 2
refName$ = "380 ohm"
scalar% = 40
sensorCode% = 9
END SELECT
INPUT "What channel is "; refName$; " reference connected to"; chan%
CALL SendByte (16 + chan%)'declare channel sensor type
CALL SendByte (sensorCode%)
INPUT "What is exact value of "; refName$; " reference"; actualValue!
CALL SendByte (224 + chan%)'issue calibrate command
CALL SendByte (calCode%)
CALL SendWord (actualValue! * scalar%)
junk% = ReadByte%'wait for 7429 to calibrate
OUT BasePort% + 1, 0'reset 7429 board