September 21, 2004

News, Ideas and Applications from Delta Tau

 

 

PRODUCT BULLETIN

Delta Tau is pleased to announce that as of December 1, 2004, we will offer ModBus/TCP Ethernet communications for all products that have Ethernet communications.

This includes Geo PMAC, Geo Brick 400, and UMAC.

This allows Delta Tau products with Ethernet to communicate to the vast array of operator panels, I/O systems, PLCs and other peripherals.

In addition, we now have a low cost peer-to-peer communications network that allows for multiple, Ethernet equipped PMAC devices to communicate with each other.

See attached diagram.

Option 15F – ModBus Communication Protocol (Software) 3A0-MODBUS-35X $99.00

The following is a summary of the features of this protocol. The complete manual will be released in November.

ModBus/TCP Specification:

           Up to four independent ModBus Client or Server Ethernet connections.

           The scheduler of ModBus Client Command Lists can be run ONCE, MAX RATE or at 4 TIMER RATES (5 msec – 1.275 sec).

           Up to 96 Client command lists that can be modified in a PMAC PLC and then restarted.

           Data logging of ModBus commands VALID, BUSY, NAK, CMDERR, ADRERR.

           Easy ModBus enabling in the PMAC by defining a USER BUFFER OF >= 256 and setting 167 ! = 0. To disable the ModBus feature set 167=0 or the USER buffer <256. This design does not change the location of any of the other PMAC buffer pointers and puts the ModBus buffer always at the last 256 memory locations. So the user’s M variables pointing to it will only need changing if the PMAC or memory size is changed.

           HOST Port PMAC RDY bit allows the ModBus communication to be suspended efficiently when such commands as a $$$ or SAVE are issued.

           Full PeWin USB or Ethernet communication allowed while ModBus communication is occurring.

           Generic PLCs provided to allow ModBus motion control of PMAC.

           Client ModBus/TCP Function Code Command Lists Supported

FC

Class

Command Description

3

0

Read Multiple Registers x 125 words

16

0

Write Multiple Registers x 125 words

1

1

Read Coils x 255 coils

2

1

Read input discretes x 255 discretes

4

1

Read Input Registers x 125 words

5

1

Write One Coil

6

1

Write a single Register

15

2

Write Multiple Coils x 255 coils

23

2

Read & Write Registers x 120 words

Thank you,

Neal Kearney

VP of Sales & Marketing

 

 

 

 

 

 

 

 

2004 - Delta Tau Data Systems, Inc.