Tutorial 7
Keysight 34970A/34972A User’s Guide 329
Multifunction Module
Digital Input
The 34907A module has two non-isolated 8-bit input/output ports which you can
use for reading digital patterns.
– You can read the live status of the bits on the port or you can configure a scan
to include a digital read.
– You can generate an alarm when a specific bit pattern or bit pattern change is
detected on an input channel. The channels do not have to be part of the scan
list to generate an alarm.
– The internal +5V pull-up circuitry allows you to use the digital input to detect
contact closures like micro-switches or limit switches. An open input floats to
+5V and is read as a “1”. An input shorted to ground is read as a “0”. An
example of a contact closure detection channel is shown below.
Limit Switch
I/O Line (1 of 8)
10 kΩ
+5 V
+
Digital Read
+TTL
Reference
(+2.1 V)
_
To Next Page
Loading...
