Maxiflex P3 PAC User Manual
33
-© Omniflex
UMM126XR18.pdf
Continuous writing of dynamic data to this area during normal system operation should be
avoided.
The CPU takes up to 15 seconds to store this data in the non-volatile memory on the CPU,
so power should not be removed for at least 15 seconds after Configuration changes have
been made.
See the DIT layout in section 15 for details of layout of this section of the DIT.
6.6 DIT Access to I/O Module Data
S
pace in the P3 CPU’s Dynamic Data Area of the DIT is reserved for I/O module scanning,
and in the P3 CPU’s Static Data Area of the DIT for I/O Module configuration. All access to
I/O data in the Maxiflex P3 is done by reading or writing to the relevant DIT Register(s).
The following DIT space is allocated in the CPU to each I/O Slot in the Maxiflex System:
I/O Type
No. of Registers per Slot
Analogue Outputs
16
Analogue Inputs
16
Digital Outputs
4
Digital Inputs
4
Configuration
100
Table 6.4 I/O Slot DIT data space allocation
The Inputs and Outputs from all the modules are grouped together in the DIT according to
their I/O Type. Each group is called a “Data Space”. This arrangement allows easy reading or
writing of multiple modules at the same time, by reading from or writing to relevant I/O Type
Data Space in the CPU’s Data Interchange Table (DIT). This can be accomplished from any
of the CPU’s network ports.
The table below identifies the start location a
nd size, in the CPU’s DIT, of each of these data
spaces, for every I/O slot. If the I/O module in that slot does not utilise a type of data, then
that data space in the DIT is not used.
Notes
:
1. The specific register contents for each type of I/O Module in each Data Space can be
found in Section 7.
2. The Module Configuration Data for I/O modules in Remote Racks is stored in the R2c
I/O Scanner on the remote rack. This information is still configured through the main
P3 PAC CPU.
