Schweitzer Engineering SEL-2032, Instruction Manual

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D.3
Date Code 20120126 Instruction Manual SEL-2032 Communications Processor
System Planning Sheet
Calculate Memory Usage
Determine the Flash Memory Required
Perform the following steps, using Table D.2 as a planning sheet:
Step 1. Estimate the desired maximum number of records (n) of each
type on each port
Step 2. Determine the memory requirements per region
1. For “20” message archive regions, use the records estimated as
n in Table D.1 .
2. For regions in which you use generic parsing, proceed with the
following:
a. Calculate the number of bytes required for each record.
For CHAR_STRING parsing, each record will require
S = 28 + NUM bytes where NUM is your size setting
for the region.
For INT_STRING or ASCII_INT parsing, each record
will require
S = 28 + 2 • NUM bytes.
For ASCII_FLOAT parsing, each record will require
S = 28 + 4 • NUM.
b. Calculate the number of blocks required per record.
If the size determined in bytes is greater than 254, the
number of blocks required per record is the record size
in bytes plus 2 divided by 256 and rounded up:
If the size determined in bytes is less than 128, the
number of records that will fit in a block is 254 divided
by the record size and rounded down:
If the size determined is greater than 128 bytes and less
than 254, you will get one record per block:
The archive memory requirements are:
Step 3. Calculate the blocks required per region
1. Round all fractions up to the nearest integer.
2. Enter the number of blocks in Table D.2 .
Step 4. Sum to determine total requirement
If the total requirement exceeds 7,168 blocks, you must use
more than one SEL-2032 or reduce the amount of data you
archive.
A
S 2 +
256
------------
=
A
1
254
S
---------
-------------- =
A 1 =
An 1 +
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