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Presentation
The Modbus serial link is used for master/slave architectures (it is necessary,
however, to check that the Modbus services used by the application have been
implemented on all devices concerned).
The bus consists of a master station and slave stations. Only the master station can
initiate the exchange (direct communication between slave stations is not possible).
Two exchange mechanisms are possible:
b
Question/response, where requests from the master are addressed to a given
slave. The master then waits for the response from the slave which has been polled.
b
Broadcasting, where the master broadcasts a message to all slave stations on the
bus. The latter execute the instruction without transmitting a response.
Description
Modicon TSX Micro/Premium PLCs provide various ways of connecting to the
Modbus serial link.
Integrated link to the TSXMicro and to the TSX SCY
p
1601
Premiummodule
1
Via integrated port on the Modicon TSX Micro processor. The TER port (8-way
mini DIN) has the Modbus RTU master/slave protocol
(1)
.
2
Via integrated port on the
TSX SCY 11601
/
21601
module for Modicon Premium
PLCs. This module has an isolated Half-duplex RS 485 serial link channel (25-way
SUB-D connector) with multiprotocol, including Modbus (with the TSX SCY 11601
module, only the Modbus protocol is supported).
TSX SCP 11
p
multiprotocol PCMCIA cards
3
A slot on Modicon TSX Micro/Premium processors and the
TSX SCY 21601
module
(2)
takes multiprotocol
TSX SCP11
p
cards, including Modbus, featuring:
4
A protective cover
5
A removable cover with fixing screws (to access a 20-way miniature connector)
6
Two indicator lamps:
-
ERR lamp: card or link fault
-
COM lamp: data transmission or reception
To be ordered separately
:
TSX SCP
/
SCY
cordset.
(1)
Modbus RTU slave Protocol with TSX 37 05/08.
(2)
This slot can also take PCMCIA card
TSX FPP 20
for Fipway networks.
Magelis XBT G
p
Modicon TSX Micro
Modicon Premium
Twido
Preventa
XPS MC
Modicon
OTB
Altivar 71
Modicon M340
Modbus
Presentation,
description
Modicon Premium automation
platform
Modbus serial link
References:
pages 5/125 ...
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Modicon
Premium
Modicon
TSX Micro
TSX
SCY 21601
TSX
SCY 11601
2
1
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