Delta AH500 Programming Manual page 108

SM408 (2 sec)
SM409 (2n sec)
SM410 (2n ms)
11. The flags related to the memory card
 SM450~SM453, and SR453
The memory card is used to backup the data in the PLC. The corresponding functions of
these special auxiliary relays and the corresponding function of SR453 are as follows.
Device
Whether the memory card exists
SM450 ON: The memory card exists.
OFF: The memory card does not exist.
Write protection switch on the memory card
SM451 ON: The memory card is write protected.
OFF: The memory card is not write protected.
The data in the memory card is being accessed.
SM452 ON: The data in the memory card is being accessed.
OFF: The data in the memory card is not accessed.
An error occurs during the operation of the memory card.
SM453
ON: An error occurs.
If an error occurs during the operation of the memory card, the error code
SR453
will be recorded.
12. The flags related to the I/○ module
 SR655~SR730 record the mapping error occurring in the module table or the error occurring
in the I/○ module.
SR655~SR730 record the mapping error occurring in the module table.
If the mapping error occurs in the module table, the corresponding bit in the special data
register belonging to this module will be ON. Users can read the value in the special data
register to get the information about the position where the error occurs. For example, when
bit 5 in SR655 is ON, users can get the information that the error occurs at slot 5 in
backplane 1.
2 sec
1 sec
2n sec
n sec
2n ms
n ms
Function
Ch a pt er 2 De v ic es
0.5 Hz
1/2n Hz
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