PEP Modular Computers Modular Computers RS485 User Manual page 319

Chapter 6 Communications Modules
FB_SSI_READ
As can be seen from figure 6.2.11.1.1, the inputs to the module are displayed
on the left-hand side of the SSI block and the outputs are indicated on the
right-hand side.
setpoint
port
ctrx
error
position
statusx
October 01, 1996
In order that the current state of the encoder
may be read, this command is issued - nor
mally in a loop built into the ISaGRAF cycle.
The read-back value appears in the position
variable.
This is the register which contains the value of the
setpoint which is sent to the SSI module with the
Command statement.
The port register is used for setting the port number
of the attached SM-SSI Module.
The control register elements; for a description of the
register please refer to the relevant section appearing
earlier.
If an error occurs then it's value appears in this
variable.
The position of the encoder following a read is
recorded in this variable.
The status register elements; for a description of the
register please refer to the relevant section appearing
earlier.
©1996 PEP Modular Computers GmbH
SMART I/O User's Manual
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