Block Transfer
Chapter 18
18-5
Data Address
The data address stores the module address of the block transfer module.
The data address must be assigned the first available address in the
timer/counter accumulated area of the data table. This depends on the
number of I/O racks being used (Table 18.B). When more than 1 block
transfer module is used, consecutive data addresses must be assigned ahead
of addresses for timer and counter instructions.
Table 18.B
Block Transfer Addressing
2slot
030
1slot
030
1/2slot
050
Block transfer data addresses should be consecutive numbers (for example
030, 031, 032, etc.). A 1-word space or boundary should be left after the
last block transfer data address. When the processor sees this boundary
word, it will not search further for block transfer data. In addition, the
processor is prevented from finding other BCD values that could, by
chance, be in the same configuration as the rack, group and slot numbers
found in block transfer data addresses.
The boundary word data bits can be set to zero manually with bit
manipulation. Use [Search] [5][3] and insert zeros. Program a Get/Put
transfer assigning Get and Put instructions to the address immediately
following the last block transfer data address (Figure 18.4). The value of
the Get instruction is set to 000 when programmed.
Figure 18.4
Defining the Data Address Area
PUT
032
000
G
032
000
Data Table
1
0
0
0
0
0
0
1
1
030
031
032
First word in accumulated area of data table
Last consecutive data address contains zero to
separate block transfer addresses from timer.
counter and storage addresses.
10378-I
