5 restrictions – Rockwell Automation 57C409 2 Channel Analog Input Module User Manual
Page 25
![background image](/manuals/580481/25/background.png)
4Ć9
4.5
Restrictions
This section describes limitations and restrictions on the use of this
module.
4.5.1
Writing Data to Registers
Registers 0Ć4 are read only and may not be written to by the
application software. Attempts to write to them will cause a bus error
(severe systemerror). The following are examples fromprograms
that write to the module and should therefore be avoided:
a. Referencing the module on the left side of an equal sign in a LET
statement in a control block or BASIC task.
b. Referencing an analog input as an output in a control block
function.
4.5.2
Use in Remote I/O Racks
This module must not be used in a remote rack. A processor module
must be located in the same rack as this 2 Channel Analog Input
module.
4.5.3
Initializing or Updating Filter Registers
A minimum of 5.5 msec. is required between programming
statements used to initialize or update the filter registers (9 and 10).