Rockwell Automation GMLC Reference Manual User Manual

Page 778

Publication GMLC-5.2 - November 1999

Using Block Transfers

741

For example, the integer data file shown below (in hexadecimal format)
gets the Maximum Negative Travel value (data parameter 12) for axis 1
from the motion controller when specified in a BTW as shown in Getting
Data from the Motion Controller in this chapter. Word 0 specifies that this
block transfer is getting (7Dxx) data parameters for axis 1 (xx11). Word 1
specifies the first item as data parameter 12 (12 decimal = 000C hex).
Word 2 specifies 32-bit floating-point format (30xx) and that one item is
to be sent (xx01). Word 3 is the end-of-block delimiter (000D).

Data Table Report

PLC-5/30

Address

N14:0

7D11

000C

3001

000D

0000

N14:10

0000

N14:20

0000

N14:30

0000

N14:40

0000

N14:50

0000

N14:60

0000

The returned value is stored in data file N7 as two 16-bit integers
representing the floating-point value. For example, a Maximum Negative
Travel value of –511.4872 is returned as C3FF in word 0 (the most
significant word) and BE5D in word 1 (the least significant word) as
shown below.

Data Table Report

PLC-5/30

Address

N7:0

C3FF

BE5D

000D

0000

N7:10

0000

N7:20

0000

N7:30

0000

N7:40

0000

N7:50

0000

N7:60

0000

See Getting Data from the Motion Controller in this chapter for more
information on the format returned values file.

If words 0 and 1 of the integer data file N7 are copied to word 0 of
floating bit file F16 in the PLC using a File Copy instruction (as shown in
32-bit Floating-Point Format in this chapter) the original floating-point
value is restored.