OPERATING PROCEDURES
MEMORY USAGE EXAMPLE
4 - 8
I-E96-624A
®
MEMORY USAGE EXAMPLE
In this example, a pair of interfaces in one-way mode has the
following mix of points in their configuration:
500 digital points (S3 of FC131 = 0)
200 analog points (S3 of FC131 = 1)
50 stations (S3 of FC131 = 2)
Distribution of 750 total points on the remote loop is among 20
modules residing in 10 different PCUs. There are five OISs on
the local loop. Each OIS receives all of the points.
Memory Usage in the Local PPT
The points are coming to the local from the remote, therefore,
Table
applies. The calculations are:
500 digital points x 16 bytes/point = 8,000 bytes
200 analog points x 30 bytes/point = 6,000 bytes
50 station points x 76 bytes/point = 3,800 bytes
Each OIS receives all 750 points:
5 OIS x 750 points x 6 bytes/point = 22,500 bytes
Total memory used in the local PPT = 40,300 bytes
Memory Usage in the Remote PPT
These points are to be sent to the local, therefore, Table
applies. The calculations are:
500 digital points x 18 bytes/point = 9,000 bytes
200 analog points x 22 bytes/point = 4,400 bytes
50 station points x 70 bytes/point = 3,500 bytes
20 modules x 10 bytes/module = 200 bytes
10 PCUs x 16 bytes/PCU = 160 bytes
Total memory used in the remote PPT = 17,260 bytes
Table 4-4. Memory Usage in Sending Communication
Point Type
Memory Bytes Required
Digital
18
Analog
22
Station
70
Remote Control Memory(RCM)
22
Remote Manual Set Constant (RMSC)
26
Device Driver
22
NOTE: Add 16 bytes for each PCU that sources Exception Reports. Add 10 bytes for each module
that sources Exception Reports.
