Sterlco M2B, Руководство пользователя

Страница: 24 / 49

23
Command And Response Example Notations
1. [nu]: “not used” at present time, (for future expansion). Undefined data,
data returned should not be used.
2. <Data>: These are ASCII characters shown in Hex notation. The upper
case alpha character set is used for values A through F. (ASCII 46h - F,
ASCII 33h - 3). Lower case is not used.
ASCII Control Character ASCII in hex Description
<stx> 02 Start of Text
<etx> 03 End of Text
<ack> 06 Acknowledgment
L 4C Filter Character
00N Process Variable Value
100N Read Set Point Value
200H Write Set Point Value
Error Messages Reported
Example:Checksum error detected by Instrument at address 32
Instrument responds to Host’s last command with Error message
<stx> L <addr> N <error code> <ack>
32h N 02h
02 4C 33 32 4E 30 32 06
(Note the absence of Checksum)
N - ASCII character (4Eh) used to denote Error Present
Table Of Error Messages Possible From Instrument
<error code>
00 - Not used.
01 = Undefined command. Command not within acceptable range.
02 = Check-sum error on received data from Host.
03 = Command not performed by Instrument (option not enabled,
restricted
read/write menu, check message)
04 = Illegal ASCII characters received in command. Instrument
accepts only ASCII characters 0 through 9. A through F and a
through f in data field.
05 = Data field error. Not enough, too many, or improper positioning of
characters in data field.
06 = Undefined command. Command not within acceptable range.