Technical data

8.3.4
RS / RT Area
The RS and RT areas contain information for the system programmer
and system internal data.
The
RS area is an area 256 words long in the internal system RAM of
the CPU. It occupies the addresses EA00H to EAFFH.
Caution
You can only write to system data words RS 1, RS 60 to
RS 63, RS 133 and RS 140.
- You can use RS 60 and RS 63 for your own purposes.
- RS 1 and RS 133 have a fixed function and influence the
processing of the program. You must only write valid
identifiers to them.
You can only read the other system data
- Writing to these system data can affect the functional
capability of your CPU and connected programmers.
The
RT area is an area 256 words long in the internal system RAM
of the CPU. It occupies the addresses EB00H to EBFFH.
You can use the entire RT area (RT 0 to RT 255) for your own
purposes.
The RS / RT area can only be cleared by an overall reset.
You can obtain the information of some of the system data (the
internal configuration of the CPU, the software release, the CP
identifier etc.) using the SYSTEM PARAMETERS online function.
Following figures 8-6 and 8-7 you will find the bit assignment of
some system data that you can evaluate using STEP 5 operations or
with the PG (refer to Section 5.3.1 for an explanation of the
abbreviations).
8
User Memory Organization in the CPU 928B
CPU 928B Programming Guide
C79000-B8576-C898-01
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