about AB-DF1 library

Projects General Guidance
1

Dear friends

hope i will get more replies

i want to communicate my PLC (MICROLOGIX -1100) with Arduino (microcontroller = ATmega328).
i am using AB-DF1 protocol for my PLC

I

My idea is something like the following:

GSM <===================> |ARDUINO| <====================> |PLC|(micrologix-1100)
<------------------ WIRELESS LINK---------> .................. <------------ RS232 link ------------------->

So I just want my PLC to be controlled whenever I send some data (like characters=A or B or ......or any other ASCII data).
Arduino is capable to communicate with PC or any other RS232 enabled device using a serial RS232 cable.

is there any library avalible IN ARDUINO which will directly communicate with AB-DF1
if yes then please provide me the link

thank you

2

To my knowledge there's no implementation of the Allen Bradley DF1 link layer protocol. In the protocol manual (http://literature.rockwellautomation.com/idc/groups/literature/documents/rm/1770-rm516_-en-p.pdf) there is some pseudo code how the protocol can be implemented. Translating this into Arduino code shouldn't be that hard.

From your communication "drawing" I guess you wanna use the Arduino as a GSM interface only. Why do you wanna terminate the link layer protocol then? I would transparently forwarding everything I get from the PLC and terminate the DF1 on the PC (the other side of the GSM I guess). This way you have a reliable link from the PC to the PLC and the Arduino is just a communication device.

3

i will use PC for one time only i.e to download the programm to PLC .
i want to read and the value of PLC which is coming from the field and also want to write it
i have came to know that modbus library is avalible in the arduino
so can i able to read and write the value of PLC using MODBUS? IF YES THEN HOW?