ADInstruments PowerLab 2/20, Руководство пользователя

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26 PowerLab Owner’s Guide
handle transducers directly unless the transducers are so labelled
(unsuitable transducers will give a very weak signal). Transducers
designed for direct connection can be provided with power and
control, since the pod connectors provide some functions of the I
2
C
output as well as alternative analog inputs to the BNC connectors. Do
not attempt to record from both the BNC and pod connectors for an
input at the same time, or the signals will compete.
Serial Port
The PowerLab is fitted with an RS-485 serial communication port. It
is not currently in use, but is meant for connection in the future to
specialised devices controlled from the PowerLab system. The serial
port provides a differential, bidirectional serial connection for
external devices supporting the RS-485 standard. The port also
provides three power supplies and a ground signal.
[4] Negative 5 V
[1] Positive 5 V
[6] Input (+) ref.
[2] Input (–)
[3] Input (+)
[5] SDA
[7] Analog ground
[*] Digital ground (metal ring)
[8] SCL
[7] Ground
[4] RS-485 low
[2] –5 V
[6] +7.5 V
[3] RS-485 high
[5] Serial out
[1] +5 V
Figure A–10
The pin assignments for the
pod connector.
Figure A–11
The pin assignments for the
serial connector.