Agilent Technologies TwisTorr 84 FS PCB, Руководство пользователя

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17 Technical Information
Data Exchange Protocols

Data Field Length: made of 2 characters, it points out the next
field length in characters. In this protocol the possible
combinations are:
02 = parameter reading request
06 = parameter, writing

Data: variable lenght, it could be 2 or 6 characters according to
the previous field content, it can be:
“=?”: in the case of parameter reading request
"000000" or "111111": in the case of YES/NO command or
parameter writing
a six numeric character string 0 to 9
pointing out the value of a configuration parameter or an analog
measure
a six character string pointing out an error

Checksum: made of 3 characters, it is the sum of the string ASCII
values up to the first character of the checksum with a 8 bit
cutting-off converted to decimal number.

CR: made of 1 character < 0xD>
All the fields are aligned to the right with the "0" character used as
pad character.
When the controller receives a frame with the correct address value
(001 in this case) it answers as detailed in the following:

for a parameter request: a frame having the same format
described before, but the first character of the "Parameter
Number" field set to 1.
Example for a low speed status request:
Master to Controller:
0010000202= ?097< 0xD >
Controller to Master:
0011000206111111016< 0xD >
where " 111111" is for low speed status ON

for a parameter writing: a frame including the parameter value
that has been set out.
186/210 TwisTorr 84 FS PCB 24 Vdc Controller User Manual / 87-901-039-01 (B)