Agilent Technologies TwisTorr 305 FS User Manual page 127

<STX> (Start of transmission) = 0x02
<ADDR> (Unit address) = 0x80 (for RS 232)
<ADDR> (Unit address) = 0x80 + device number (0 to 31)
(for RS 485)
<WIN> (Window) = a string of 3 numeric character indicating the window
number (from '000' to '999'); for the meaning of each window see the
relevant paragraph.
<COM> (Command) = 0x30 to read the window, 0x31 to write into the
window
<DATA> = an alphanumeric ASCII string with the data to be written into
the window. In case of a reading command this field is not present. The
field length is variable according to the data type as per the following
table:
Tab. 13
Data Type
Logic (L)
Numeric (N)
Alphanumeric (A)
<ETX> (End of transmission) = 0x03
<CRC> = XOR of all characters subsequent to <STX> and including the
<ETX> terminator. The value is hexadecimal coded and indicated by two
ASCII character.
The addressed SLAVE will respond with an ANSWER whose structure
depends from the MESSAGE type. When the MESSAGE is a reading
command, the SLAVE will respond transmitting a string with the same
structure of the MESSAGE.
Using the RS 485 interface, the message structure remains identical to the one
NOTE
used for the RS 232 interface, the only difference being that the value assigned
to the ADDRESS <ADDR>
The controller can answers with the following response types:
TwisTorr 305 FS Remote Controller User Manual / 87-901-059-01
Letter Protocol Description
Field Length Valid Characters
1 '0' = OFF
'1' = ON
6 '-', '.', '0' . . . '9' right justified with '0'
10 from blank to '_' (ASCII)
Technical Information
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