Despatch Protocol 3 Modbus Communications - Manual (Page 48)

A DDRESS LIST Modbus Programming Manual
48 Version 2
Copyright © 2012 by Despatch Industries.
All rights reserved. No part of the contents of this manual may be reproduced, copied or transmitted in any form or by any
means including graphic, electronic, or mechanical methods or photocopying, recording, or information storage and
retrieval systems without the written permission of Despatch Industries, unless for purchaser's personal use.
Read A Segment - Request (to instrument)
Field Name Data Comments
(Dec) (Hex)
Read Quantity Of Registers High Byte 00 00
Read Quantity Of Registers Low Byte 11 0B
Write Start Address High Byte 32 20
Write Start Address Low Byte 06 06
Write Quantity Of Registers High Byte 00 00
Write Quantity Of Registers Low Byte 03 03
Byte Count 06 06
Command Code High Byte 82 52
Command Code Low Byte 83 53
Profile Number High Byte A/R A/R Number of the profile to read
Profile Number Low Byte A/R A/R
Segment Number High Byte A/R A/R Number of the segment to read
Segment Number Low Byte A/R A/R
CRC High Byte A/R A/R
CRC Low Byte A/R A/R
The instrument replies to the Read A Segment request as follows:
Read A Segment - Response (from instrument)
Field Name Data Comments
(Dec) (Hex)
Unit Address A/R A/R The ID address of the instrument
Function Code 23 17 The multi read/write function
Byte Count 02 18
Command Response High Byte 82 52
Command Response Low Byte 83 53
Profile Number High Byte A/R A/R Echo of the profile number requested
Profile Number Low Byte A/R A/R
Segment Number High Byte A/R A/R Echo of the segment number requested
Segment Number Low Byte A/R A/R
Segment Type High Byte 00 00 0 = Ramp Time, 1 = Ramp Rate,
2 = Step, 3 = Dwell, 4 = Hold, 5 = Loop
6 = Join, 7 = End, 8 = Repeat sequence
then end
Segment Type Low Byte A/R A/R
Segment Info A (Byte 4 - High)
Floating point number
The meaning of the data contained in
Segment Info A depends on the type of
segment it relates to. See below.
Segment Info A (Byte 3)
Segment Info A (Byte 2)
Segment Info A (Byte 1 - Low)
Segment Info B (Byte 4 - High)
Floating point number
The meaning of the data contained in
Segment Info B depends on the type of
segment it relates to. See below.
Segment Info B (Byte 3)
Segment Info B (Byte 2)
Segment Info B (Byte 1 - Low)
Auto Hold Type High Byte A/R A/R 0 = Auto-Hold Off, 1 = Hold above SP,
2 = Hold below SP,3 - Hold above and
below SP
Auto Hold Type Low Byte A/R A/R