User guide

Hardware
890 USE 108 00 August 2001 17
This is the example table.
For this example, you should set the IEC memory size to 97. The figures for other
PLC models (E984-258/265/285) will vary due to internal reserved memory
allocations.
SRAM Shared
memory Space of
E984-275
Requirements Specific Items Memory Allocations
16K words in 984
Ladder Logic or
204K bytes in IEC
Modbus master XMIT loadable
NSUP loadable
17K bytes
6K bytes
AGA flow GD92 Loadable 52K bytes
IEC ST (20K bytes*20%**)=22K bytes
Subtotal IEC
space needed
97K bytes
984LL 984LL space
needed
(3K words*14***)=42K bytes
Total memory
space used
139K bytes
Memory space
remaining
(204K bytes-139K bytes)=65K
bytes
Use of remaining
68K bytes of
space
In IEC: (65K bytes-20%)=52K
bytes In 984LL: (65K bytes/
14)=4.6K bytes
**We recommend allocating 20% spare RAM space in IEC. ***14 is a constant conversion
factor.****When using the GD92 loadable you must use LSUP, not NSUP