SUPMEA SUP-2100H Series, Руководство пользователя

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Chapter 6 Communication Protocol
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returning data followed with two bytes of CRC check sum, which is the adding sum
of the original character string.
Take the DI+(CR) command as an example. Assume that DI+(CR) would return
+10m3(CR)(LF)( the string in hexadecimal is 2BH, 31H, 32H, 33H, 34H,
35H, 36H, 37H, 45H, 2BH, 30H, 6DH, 33H, 20H, 0DH, 0AH) , then PDI(CR) would
10m3!F7(CR)(LF). ‘!' acts as the starter of check sum which is
yielded by adding up the string 2BH, 31H, 32H, 33H, 34H, 35H, 36H, 37H, 45H,
2BH, 30H, 6DH, 33H, 20H.
Please note that there will be SPACES (20H) before‘!'.
(2) Prefix W
The prefix W should be used in the network environment. The usage format is w +
digit string which stands for the IDN + basic command.
The digit string should have a value between 0 and 65534 except 13(0DH), 10
(0AH), 42(2AH,*), 38(26H, &).
For example, if the IDN=12345 instrument is addressed and returning the velocity
of that instrument is requested, the command will be w12345DV(CR).
(3) Prefix N
The prefix N is a single byte IDN network prefix, not recommended in a new design.
It is reserved only for the purpose of the compatibility with the former versions
(4) Command Connector &
The & command connector can connect up to 6 basic commands to form a longer
command so that it will make the programming much easier.
For example, assume that the measurement of an instrument with IDN=4321 are
going to be returned, and (then) all the following 3 values... (1) flow rate (2) velocity
(3)POS totalizer...will be returned simultaneously. The combined command would
be W4321DQD&DV&DI+(CR), and the result would be:
+1.12m3/d(CR)
+3.100m/s(CR)
+10m3(CR)
6.4 Codes for the Keypad
The codes for the keypad should be used when the instrument is connected with