Allen-Bradley InView Marquee 2706-P42, User Manual

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Publication 2706-UM016A-EN-P - June 2002
InView Protocol 9-37
Updating Variables using a Modbus ASCII 10 frame in Guaranteed
mode
This method will allow the ability to update more than one variable in
a specific display address. A maximum of 60 registers can be updated
in one transmission. Unused high order bits must be set to zero. The
following is an example of updating variables 1, 2, and 3 with values
23, 734, and 7 respectively in display address 003.
Below is an example of a preset multiple register transmission.
Transmission:
Figure 9.56 Query for Updating Variable Registers using a 10 Frame
Response:
The normal response to a function 10 query is to echo the address,
function code, starting address and the number of registers that were
loaded.
Figure 9.57 Response for Updating Variable Registers using a 10 Frame
Beg of
Frame ADDR FUNC H.O.
ADDR L.O.
ADDR QUANTITY BYTE CNT DATA
: 03 10 00 00 0003 06 0017 02DE 0007
LRC
Error EOF Ready
to rec.
resp
E6 CR LF
TIP
Using the Guaranteed mode for variable updates,
messages may not be displayed as expected.
Beg of
Frame ADDR FUNC H.O.
ADDR L.O.
ADDR QUANTITY LRC
Error EOF Ready to
rec. resp
: 03 10 00 00 0003 EA CR LF
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