FieldServer FS-8704-13 - Manual (Page 11)

FS-8704-13 GE-SRTP Driver Manual
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Page 9
4.4.6 Map Descriptor Example 3 – Handling Bits.
This example shows how to read 1 couple of bits from a data table rather than reading a whole byte. The bits can cross byte boundaries. Here we read 2 bits
from table %T starting at bit 8. This is most useful when writing to the PLC in cases where you want to turn o ne particular bit on or off.
Map_Descriptor_Name, Data_Array_Name, Data_Array_Offset, Function, Scan_Interval, node_name, Address, Length, Data_Type, Format
Read_DI , DA_T , 100 , rdbc , 2.0s , PLC-1 , 8 , 2 , %T , Bit
The format parameter tells the
driver to override the default data
type and to specifically read bits. In
this case the bit states are stored in
the data array in two separate
elements at DA_T[100] and
DA_T[101]