Agilent Technologies 969-9462, User Manual

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17
Technical Information
Optional Serial Port
Message Structure
(request and answer have the same format)
The master system (PC) starts every session sending the following
message to the slave units connected:
<STX> / <ADDR> + <WINDOW> + <COMMAND> + <DATA> + <ETX>
+ <CRC>
where:
<STX>= 0x02
<ADDR> = 0x80 (for RS 232 and RS 422 only)
<ADDR> = 0x80 + device number (0...31)
0xFF: brodcasting command (recognized by all the
devices, it doesn’t implicate any answer)
(for RS 485 only)
<WINDOWS>= ' 000 '...' 999' window number the meaning of the
window depends to the device type
<COMMAND>= 0x30: window value reading
0x31: window writing
<DATA> = alphanumeric ASCII string containing, in the case of
writing operation,the parameter to input into the
window addressed by the field <WINDOW>This
field may have variable length according to the data
type contained in the windo where you are working
in. In the case of reading request of a window, the
data field doesn’t exist.
<ETX>= 0x03
<CRC>= XOR among all the characters following
<STX>=(with exception of <STX>), including the end
character <ETX> hexadecimally encoded by two
ASCII characters.
256/306 Turbo-V 2000HT Controller User Manual / 87-900-913-01 (O )