Siemens SIMATIC TI545, Системное руководство

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Starting Up the TI555 System
6-5 TI545/TI555 System Manual
6.3 TI555 CPU Memory Configuration
The TI555 CPU memory is user configurable. The actual ranges of memory
types for each model of the CPU depend upon how the memory has been
configured. Ranges for memory types are listed in Table 6-2.
You can increase the memory allocated to a particular memory type, a block
at a time, up to the maximum listed in Table 6-2. Block sizes vary with the
memory type as shown in Table 6-2.
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 384K bytes of system memory are available on the PPX:555–1101
CPU, and up to 1920K bytes on the PPX:555–1102 CPU. You cannot
configure all memory types to their maximum allocation size
simultaneously. For example, (for the TI555–1101) if you configure
V-memory to 369K bytes, then you cannot configure S-memory to 368K
bytes because the 384K bytes of system memory would be exceeded.
Refer to your TISOFT manual and SIMATIC TI505 Programming Reference
manual for additional information on memory configuration.
Table 6-2 TI555-1101/1102 CPU Memory Configuration
Memory Type
Block
Allocation
Size
Memory
Required
per Block
Minimum
Size
Maximum
Size
–1101 –1102
Total Memory
Required for
Maximum Size
–1101 –1102
Ladder (L) 1K bytes 3K bytes 1K bytes 123K bytes 635K bytes 369K bytes 1905K bytes
Variable (V) 1K bytes 1K bytes 1K bytes 369K bytes 1905K bytes 369K bytes 1905K bytes
Constant (K) 1K bytes 1K bytes 0K bytes 368K bytes 1904K bytes 368K bytes 1904K bytes
Special (S) 1K bytes 1K bytes 0K bytes 368K bytes 1904K bytes 368K bytes 1904K bytes
User (U) 1K bytes 1K bytes 0K bytes 368K bytes 1904K bytes 368K bytes 1904K bytes
Timer 1024* 5K bytes 1024* 20480 20480 100K bytes 100K bytes
Drum 64* 3K bytes 64* 2304 2304 108K bytes 108K bytes
Shift Register 1024* 1K bytes 1024* 16384 16384 16K bytes 16K bytes
Table Move 1024* 2K bytes 1024* 14336 14336 28K bytes 28K bytes
One Shot 1024* 1K bytes 1024* 32768 32768 32K bytes 32K bytes
*Number per block.
Memory
Configuration
Maximum
Configurable
Memory