Technical data

6.31.2
OB 240: Initializing Shift
Registers
Application Before processing a shift register, you must first initialize it. This is
done by calling OB 240 once (ideally in a restart organization block).
The parameters that OB 240 requires to create a shift register are
contained in a data block with the number of the shift register to be
initialized. DB numbers between 192 and 255 are permitted.
Function A specific memory area at the end of the DB-RAM is reserved and
initialized with the information from the opened data block.
Parameters opened data block
possible values: DB no. 192 to 255
The data block has a fixed structure which you must not change. It
can have a maximum length of 9 data words (DW 0 through DW 8).
Number of the 1st flag byte/base pointer
Shift register length (bytes) L
Interval n
2
3
5
4
6
Interval n
Interval n
Interval n
Interval n
DW 0
DW 1
DW 2
DW 3
DW 4
DW 5
DW 6
DW 7
0
0
DW 8 or last data word
Fig. 6-19 Structure of the data block for initializing a shift register
6
OB 240 to 242: Special Functions for Shift Registers
CPU 928B Programming Guide
C79000-B8576-C898-01
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