Mercury 2+, Руководство пользователя

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Mercury 2+ Operator Terminal User Manual Page 51 of 82 2019r0
Appendix B
Examples of how to use the Mercury 2+ escape codes to complete
actions are given below. Take a few minutes to familiarise
yourself with the method for designing blocks and messages, or
graphic images.
This example runs through the method to send a text message to a
Mercury's display. The text used in this example is the word
"TEST".
Using the format of a block, we can examine how it is composed:­
"<STX> ADDR FUNC DATA DMY CSUM <ETX>"
<STX> character always starts a block and is sometimes known as
the Control B character. The terminal needs to receive the
character Hex value 02
H
.
ADDR
Before any transmission is made, determine the destination
terminal address. This address is set manually in the Set­up mode
on the terminal and is a number between 1 and 15. The ADDR
field is a two byte field. So if the destination terminal address is 1,
then the field must contain 01.
FUNC
The FUNC byte is a "D" (44
H
) for messages transmitted from the
Mercury 2+ terminal and "R" (52
H
) for messages received by the
Mercury 2+ terminal. In this example this byte must be "R".
DATA
A field of variable length, this contains the "message" to be
transmitted whether it is text or a control character string. In this
example the word "TEST" is being transmitted.
<ETX>
The <ETX> character always ends a block and is sometimes
known as the Control­C character. The terminal needs to receive
the <ETX> character that has the value 03
H
.
Using Mercury 2+ in
Multi-drop Mode
Text Transmission