I 2 C Expansion Connector - ADInstruments POWERLAB TEACHING SERIES Owner's Manual

Figure 4-7
The pin assignments
for the digital input
and output
connectors
2
I
The I2C port on the back panel of the PowerLab 2/26, 4/26 and 26T provides expansion
support for ADInstruments front-ends. This port provides both power and control
signals for these front-ends. The I2C bus has a daisy-chain structure that allows simple
connection of additional front-ends to the system. A PowerLab can have as many front-
ends connected to it as it has analog input connections. You should not attempt to run
other external devices from the I2C port: it is designed for use only with ADInstruments
front-ends. Only 50 mA maximum current can be provided through this bus, so it should
not be used for third-party devices as they may draw more current.
Figure 4-8
The pin assignments
for the I 2 C connector
35
Digital Input
1
9
C Expansion Connector
Front-end power
5
9
Digital Output
8
15
I2C control signals
1
6
PowerLab Teaching Series - Owner's Guide
8
15
1
9