Delta Tau PMAC Pack, Hardware Reference Manual

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PMAC-Pack
34 Getting Started
Figure 2-9. Connection of Input in Sourcing Configuration
Setting-up PMAC to Read the I/O
Machine inputs and outputs are typically accessed in software through the use of M-variables. In the
suggested set of M-variable definitions (see Chapter 9 of PMAC Software manual), variables M1 through
M8 are used to access outputs 1 through 8, respectively, and M11 through M18 to access inputs 1 through
8, respectively. The JOPT ports map into PMAC's memory space at Y address $FFC2. Setup M-Variables
to point at the specific I/O points (bits) of Y:FFC2 as shown in Table 2-3.
Testing the I/O
Testing an Output
Using the terminal window of the PMAC Exec, type
M01=0 <CR>
. Now type
M01=1 <CR>
. You
should see the LED or corresponding device interfaced to Machine Output #1 (pin 11) change state. Type
M01=0 <CR>
again. The device should return to the original state.
Testing an Input
To query the status of Machine Input #1, type M11 <CR> in the terminal window of the PMAC Exec.
PMAC will respond with a 1 or 0, depending on the state of the input. Toggle the input state and again
query the input value. You should see the corresponding change of state in software.