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Series 2600B System SourceMeter® Instrument Reference Manual
Section 3: Functions and features
2600BS-901-01 Rev. B / May 2013
3-87
Remote digital I/O commands
Command
Description
digio.readbit(
bit
)
Read one digital I/O input line
digio.readport()
Read digital I/O port
digio.writebit(
bit, data
)
Write data to one digital I/O output line
digio.writeport(
data
)
Write data to digital I/O port
digio.writeprotect =
mask
Write protect mask to digital I/O port
Digital I/O programming example
The programming commands below illustrate how to set bit B1 of the digital I/O port high, and then
read the entire port value.
digio.trigger[1].mode = digio.TRIG_BYPASS
-- Set Bit B1 high.
digio.writebit(1,1)
-- Read digital I/O port.
data = digio.readport()
Using output enable
Output enable is available on Models 2601B/2602B/2604B only.
Output enable overview
The Model 2601B/2602B/2604B digital I/O port provides an output enable line for use with a test
fixture switch. When properly used, the output of the will turn OFF when the lid of the test fixture is
opened. See
DUT Test Connections
(on page 2-48) for important safety information when using a
test fixture.
When an interlock is required for safety, a separate circuit should be provided that meets
the requirements of the application to reliably protect the operator from exposed voltages.
The digital I/O port of the Model 2601B/2602B/2604B is not suitable for control of safety
circuits and should not be used to control a safety interlock.
Operation
When enabled, the output of the Model 2601B/2602B/2604B can only be turned on when the output
enable line is pulled high through a switch to +5 V (as shown). If the lid of the test fixture opens, the
switch opens, and the output enable line goes low, turning the output of the System SourceMeter
®
instrument off. The output will not automatically turn on when output enable is set high. The output
cannot be turned back on until +5 V is applied to the output enable line.
Summary of Contents for System SourceMeter 2601B
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