Table of Contents
Advertisement
...8 COMMUNICATION
8.3 Reply Format – Figs 8.4 to 8.6
The C300 Controller replies to the command
using the reply format shown in Figs. 8.4 to
8.6.
8.3.1 Term
Clarification for Reply Format
Instrument Identification
identifying the C200 Controller, 01 to 99.
– usually up to six characters (including
Data
decimal point) showing the new parameter
value.
However, up to 12 characters may be used if
identifying the Alarm Relay Assignment, i.e.
when using mnemonics Q1, Q2.
Instrument
Identification
(01 to 99)
Instrument
Identification
(01 to 99)
First reply
Note. This reply format may be repeated several times – see Example c) overleaf
Replies
2 to n
The last reply line is always:
Last reply
(n+1)
8
– two characters
Parameter
Mnemonic
(Section 8.6)
Sign
Fig. 8.4 Reply Format (Command Understood)
Parameter
Mnemonic
(Section 8.6)
Sign
Fig. 8.5 Multiple Read Reply Format
Instrument
Identification
(01 to 99)
Fig. 8.6 Reply Format (Command Not Understood)
– two-character mnemonic – see
Error Code
Section 8.5.
– one ASCII control character (see
Reply
Appendix A1):
'ACK' – command understood
'NAK' – command not understood
'ETB'
– end of multiple read reply
Block Check Character (BCC)
the arithmetic sum of the complete message
(excluding parity bits), transmitted by the
controller for error detection – see Appendix
A3 on page 28.
Data (up to 12 characters)
Data (up to 12 characters)
Error Code
Reply
NAK
block.
– one character,
BCC
Reply
(optional)
ACK
Reply
(optional)
ETB
ETB
ETB
ACK
BCC
(optional)
BCC
Hide quick links:
Advertisement
Table of Contents
