Keithley 2002 User Manual page 323

Example Programs
Four-Wire Ohms Measurements
Microsoft QuickBASIC 4.5
IOtech Interface and Driver-488 Software
©1992, Keithley Instruments, Inc.
Description
This program configures the Model 2002 to make four-wire
ohms measurements. The Model 2002 makes five measure-
ments, stores them in its internal buffer and then sends them
to the computer where the readings are displayed. This pro-
cess continues until a keystroke occurs to stop the program.
Program (ohmsbufi.bas)
OPEN "\dev\ieeeout" FOR OUTPUT AS #1
IOCTL #1, "break"
PRINT #1, "reset"
OPEN "\dev\ieeein" FOR INPUT AS #2
CLS
PRINT #1, "TIME OUT 5"
PRINT #1, "TERM OUT LF EOI"
PRINT #1, "TERM IN LF EOI"
'--- Set up 2002 for 5 readings, 7.5 digits, 4-wire ohms, 10 NPLC, store
'readings in buffer, return buffered readings to host computer and then
'repeat the process.
PRINT #1, "Output 16; *RST"
PRINT #1, "Output 16; :sens:func 'fres';"
cmd$ = ":sens:fres:nplc 10; dig 7.5; aver:coun 5; tcon rep;"
cmd$ = cmd$ + "Stat On"
PRINT #1, "Output 16;"; cmd$
PRINT #1, "Output 16; :form:elem read"
cmd$ = ":init:cont off; :abor; :trac:cle"
PRINT #1, "Output 16;"; cmd$
cmd$ = ":arm:seq1:lay1:sour bus; coun 1; :arm:seq1:lay2:sour imm;"
cmd$ = cmd$ + ":trig:seq1:sour imm; coun 5; :stat:meas:PTR 512; NTR 0"
PRINT #1, "Output 16;"; cmd$
G-6
This program configures the Model 2002 as follows:
Function: 4
Filter: Repeat averaging mode, 5 readings
Resolution: 7 1/2 digits
Required equipment
• Model 2002 Multimeter
• Microsoft QuickBASIC 4.5
• IOtech GP488B IEEE-488 Interface
• IOtech Driver488 Software (installed and configured as
described in the instruction manual for the interface).
The program assumes that the Model 2002 is set to address
16.
' Open GP488B for output
' Reset Personal488
' Open GP488B for input
' Perform reset
' Set for 4-wire ohms
' Set for 10 PLC,
' 7.5 digits, average
' 5 readings, repeat mode
' Return readings only
' Turn off trigger model,
' Clear data buffer
' Set the 2002 to start
' taking readings on a
' bus trigger. Set Measure
' Event Register to flag
' on buffer full.