YOKOGAWA F3LC11-1F, User Manual

Page: 183 / 202

C4-7
IM 34M6H41-01E 3rd Edition : Aug. 1, 2005-00
[2] Response Format and its Elements
The format of a response that is sent back from the FA-M3 to a higher level computer
(or display) is shown here. For the meaning of each element, refer to item [1], “Command
format and its elements.” For more details, see the “Personal Computer Link Commands”
manual (IM34M6P41-01E).
(1) If communication is normal
1 2 2 1 1 2 2
OK
No. of bytes
Variable length
Element STX
Station
number
(SA)
CPU
number
(nn)
Command response
Checksum
(SUM)
ETX CR
FC040101_3.EPS
Appended to the
response only when
it is appended to the
command.
In normal communication, the character string “OK” and the command response are
returned.
(2) If a communications error has occurred
1 2 2 3 2 1 1
CR ETX STX
2
ER
2
EC1
2
EC2
FC040101_4.EPS
Appended to the
response only when
it is appended to the
command.
No. of bytes
Element
Station
number
(SA)
CPU
number
(nn)
Command Checksum
(SUM)
If a communications error occurs, the character string “ER” and two error codes (EC1
and EC2) are returned.
EC1: Error code (see Table C4.1)
EC2: Detailed error code (valid only if EC1 is 03, 04, 05, 08, 41 and 52. See
Table C4.2)
• If an invalid CPU number is specified, the CPU number (2 bytes) received by this
module is returned as the CPU number.
• In case of a station number error, no response is returned.
• If ETX (End of Text) is not received, a response may not be returned. Be sure to
perform timeout processing in the higher level computer or display.