Ti545 Cpu Memory Configuration; Memory Configuration; Maximum Configurable Memory; Table 6-1 Ti545-1102 Cpu Memory Configuration - Siemens SIMATIC TI555 System Manual

6.2

TI545 CPU Memory Configuration

Memory
Configuration
Maximum
Configurable
Memory
Memory Type
Ladder (L)
Variable (V)
Constant (K)
Special (S)
User (U)
Timer
Drum
Shift Register
Table Move
One Shot
*Number per block.
Starting Up the TI555 System
6-4
The TI545 CPU memory is user configurable. The actual ranges of memory
types depend upon how the memory has been configured. Ranges for
memory types are listed in Table 6-1.
You can increase the memory allocated to a particular memory type, a block
at a time, up to the maximum listed in Table 6-1. Block sizes vary with the
memory type as shown in Table 6-1.
Some overhead is associated with certain memory types. For example, each
K byte of L-memory uses a total of 3K bytes of system memory. Each
timer/counter uses 5 bytes of system memory. A drum uses 48 bytes.
When you increase L-memory by one block, from 16K bytes to 20K bytes,
system memory reserved for L-memory increases from 48K bytes to
60K bytes. When you increase the number of drums by one block, from 64 to
128, system memory reserved for drums increases from 3K bytes to
6K bytes.
Up to 192K bytes of configurable system memory are available on the TI545
CPU. You cannot configure all memory types to their maximum allocation
size simultaneously. For example, if V-memory is configured to 177K bytes,
then S memory cannot be configured to 176K bytes because the 192K bytes
of system memory would be exceeded.
Refer to your TISOFT manual and SIMATIC TI505 Programming Reference
manual for additional information on memory configuration and configuring
I/O.

Table 6-1 TI545-1102 CPU Memory Configuration

Block Memory
Allocation Required
Size per Block
1K bytes 3K bytes
1K bytes 1K bytes
1K bytes 1K bytes
1K bytes 1K bytes
1K bytes 1K bytes
1024* 5K bytes
64* 3K bytes
1024* 1K bytes
1024* 2K bytes
1024* 1K bytes
Minimum Maximum
Size Size
1K bytes 59K bytes
1K bytes 177K bytes
0K bytes 176K bytes
0K bytes 176K bytes
0K bytes 176K bytes
1024* 4096
64 512
1024* 3072
1024* 3072
1024* 7168
Total Memory
Required for
Maximum Size
177K bytes
177K bytes
176K bytes
176K bytes
176K bytes
20K bytes
24K bytes
3K bytes
6K bytes
7K bytes
TI545/TI555 System Manual