Keithley 2601A User Manual

2600AS-900-01 Rev. B / September 2008 Return to Section Topics A-3
Series 2600A System SourceMeter
®
Instruments User’s Manual Appendix A: Frequently Asked Questions
How do I use the Digital I/O port?
Digital I/O port terminals
The Digital I/O port, located on the rear panel (see Figure 1-2), provides 14 digital I/O lines (Figure
A-1). Each output can be set high (+5V) or low (0V), read high or low logic levels, and can be set
up for triggering. Make connections using a cable with a Male DB-25 connector (Keithley
Instruments part number CA-126-1).
Figure A-1
Digital I/O port terminals
Controlling the digital I/O port
From the front panel, select MENU > DIGOUT > DIG-IO-OUTPUT, then enter the decimal value to
set I/O lines high or low (16,383 maximum). Commands for basic I/O are summarized in
Table A-1.
For example, to set all 14 lines high, send:
digio.write.port(16383).
How do I trigger other instruments?
Triggering a scanner
A typical test scenario might call for using the Series 2600A with a scanner to test a number of
DUTs in sequence. A basic example that uses the Series 2600A Digital I/O port to trigger a
scanner is shown in
Figure A-2. In this case, line 1 of the I/O port is used as a trigger output and
connected to the scanner mainframe trigger input, while line 2 of the I/O port is used as a trigger
input.
Table A-1
Commands for basic I/O port
Command Description
digio.readbit(bit)
digio.readport()
digio.writebit(bit, data)
digio.writeport(data)
Read one digital I/O input line.
Read digital I/O port.
Write data to one digital I/O output line.
Write data to digital I/O port.
1 = Digital I/O #1
2 = Digital I/O #2
3 = Digital I/O #3
4 = Digital I/O #4
5 = Digital I/O #5
6 = Digital I/O #6
7 = Digital I/O #7
8 = Digital I/O #8
9 = Digital I/O #9
10 = Digital I/O #10
11 = Digital I/O #11
12 = Digital I/O #12
13 = Digital I/O #13
14 = Digital I/O #14
15-21 = Ground
22 = +5V
23 = +5V
24 = Output Enable (OE); 2601/2602
24 = Interlock (INT); 2611/2612/2635/2636
25 = +5V
1
14
13
25
DIGITAL I/O

Keithley 2601A Specifications

General

Brand	Keithley
Model	2601A
Category	Measuring Instruments
Language	English