Omron SYSMAC CJ Series, Operation Manual

Page: 172 / 371

All BASIC commands Section 4-2
160
Arguments • option
Depending of the value of this argument, either the whole, or just a
part of the
TABLE memory is stored. The valid values for the argu-
ment are:
-1: The whole
TABLE memory content is written to flash
memory. On power-up the RAM TABLE data are replaced by the
data saved in flash memory.
-2: Stop using data stored in flash to replace RAM TABLE data
during start-up.
-3: Write a page of TABLE data into flash memory.
-4: Read a page of flash memory into TABLE data.
• flashpage
The index number in range [0…31] of a 16k page (512k in total) of
the flash memory where the table data is to be stored (option = -3) or
retrieved from (option = -4)
• tablepage
The index number in range [0…3] of a 16k page it TABLE memory
where the table data is to be copied from (option = -3) or restored to
(option = -4).
Note: When the FLASHVR(-1) is executed, the whole range (all 64000
slots) of the TABLE memory is written to the flash memory and restored
from flash memory on start-up. If, for example, only 1000 TABLE mem-
ory in range [0…999] are defined, in which case an attempt to read
TABLE(1000) would result in "Index range error", executing
FLASHVR(-1) would write already defined values of TABLE memory in
range [0...999] into the flash memory, but also all other TABLE memory
slots in range [1000…63999] will be written to the flash memory with
undefined values. On start-up, the whole range of
TABLE memory
[0…63999] would be restored from flash memory, so for example an
attempt to read previously undefined slot
TABLE(1000) would succeed,
but the value is undefined. The similar behaviour applies to executing
FLASHVR(-4, flashpage, tablepage) . It the current defined range of
the TABLE memory is narrower that the one of the retrieved data, the
range of TABLE memory will be extended automatically.
Note: FLASHVR(-1) writes the whole range (all 64000 slots) of the
TABLE memory in flash memory starting from flashpage 0. Once
FLASHVR(-2) is executed, the RAM TABLE data are not replaced on
start-up by the data saved in flash memory, but that data is still available
in flash memory, and can be retrieved in any tablepage by using
FLASHVR(-3, flashpage, tablepage) command.
Note: Each FLASHVR command generates a write to a block of the
Flash memory. Although this memory allows numerous writes and
erases, it has a limited life cycle. Programmers should be aware of this
fact and use the command as limited as possible.