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Invert in – Measurement Computing Digital232 User Manual

Page 36

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Section 3

Command Descriptions

3.14

Invert In

The Invert command is used to change the polarity of the handshake and data

lines. At power up all handshake and control lines are active high (logic one = + 5
volts). The Invert command can selectively change the polarity of each of the
handshake lines, and of the data lines. If multiple Invert commands are contained
within the same string, then an Execute command (X) should be included between
each Invert command. An alternative is to add the values of each Invert command
desired, and send one command with the sum of the desired commands. The Invert
commands are Ored together as received. To delete any one command, it is necessary
to program the default mode I0, then re-program the desired commands.

I0

All control lines are active high, all data lines are high true.

I1

Inhibit output is active low

I2

Trigger output is active low

I4

Data Strobe output is active low

I8

Clear output is active low

I16

Data is low true

I32

EDR input is falling-edge sensitive

I64

Service input is falling-edge sensitive

Example:

@

reset the Digital 232

I32XI64

select EDR and Service input as
falling-edge sensitive

note:
I96

performs the same function as above