Red Lion Data Station Plus connecting to Mitsubishi FX

Yes there must be a way of forcing the port to communicate at a higher rate. Beijers must use the same method but I have not really looked into it.
klauricella, Have you tried to connect to the programming port to see if that works, I bet most people that have used that unit use the programming port.

Beijer is a close Mitsubishi partner even, manufactures accessories such as the well known red SC-09 cable. Surely Mitsubishi shared the secret with them.

Well I know they used to be, But Mitsubishi dropped the HMI Range in favour of their own got so I think the only reason that Beijers predominantly produce equipment that connects to Mitsubishi is the large customer base that has been built up during their partnership. Mitsubishi visited me a few years ago and told me that they were dropping the E range in favour of the Got. They also told me that the E range was redundant, however I found out from Beijers that at that time there was no End of Life planned in the next 3-4 years. This proved to be true. They explained that they had such a large customer base predominantly connected to Mitsi. that it would be commercial suicide to drop it so quickly. It is only in the last few years that they have moved on. The new ranges will import the old E series files, however I have not personally tried it. When I upgraded some 40 older E700 - 900 the upgrade was easy, only downside was graphics positioning due to screen size changes and recipes changing from 8.3 format, this only posed a problem if the recipe was loaded via PLC code rather than the HMI functions, unfortunately in our case this caused some modifications to the recipe handling in the PLC's.

Ok before I fix this thing permanently with a hammer I set it up as a Modbus master and the FX3U as a slave. I use Modbus about once every ten years so I am not that good with it but have a basic understanding of it. Using the example out of the Mitsubishi manual set it and tried the default addressing. I am getting info just not sure where it is coming from. I have tried switching bits and bytes and still doesnt look right. If I create a tag in the DSPSX for a holding register and set it at 400001 should it read D0. According to the manual it shows 0x0000-0x1F3F to be D0-D7999. I am missing something have been going around in circles with this thing so a little confused at this point.


Thanks
Kevin

40001 for 5 digit addressing or 400001 for 6 digit is the the Modbus address of the first register in the Holding Registers area.
But so many manuals instead to indicate the correct Modbus address they use an offset in the Holding Register area, then you should add this offset to 400001.

400001 will be D0 and 408000 will be D7999

parky said:

Yes there must be a way of forcing the port to communicate at a higher rate. Beijers must use the same method but I have not really looked into it.
klauricella, Have you tried to connect to the programming port to see if that works, I bet most people that have used that unit use the programming port.

Click to expand...

I have not try the programming port because there is an HMI plugged into that plus I do not have that cable. I do have it talking thru Modbus now and pretty sure the addressing is correct but the data is just random values. I have checked the FX memory and these values do not appear anywhere. There is also no serial errors or Modbus errors. I have tried different baud rates but that also didn't seems to help. So the battle continues.


Thanks
Kevin

I have attached a screen shot of the DSPSX Modbus master settings and the FX program setup. I believe everything is correct but at this point not really sure.


Thanks
Kevin

Ok let me try this again

Have you read this manual.
http://www.inverter-plc.com/plc/melsec/FX3U SERIES PLC,MODBUS Serial Communication Edition.pdf

Yes I have plus a few others. Thanks

Not knowing the redlion I'm afraid I have just about run out of ideas, I don't understand the addressing in redlion for D0, Only other is it RTU or ASCII.
By the way I have a 2lb hammer if you want to borrow it.

I ave made a little progress. The Red Lion and FX are talking just not sure what. I have mapped a gateway block from a Compactlogix tag to holding register 400001 (which should be D0) and then another gateway block from 400001 to a different tag in the Compactlogix. This kind of works when I change the value in the first tag it sends that value out and it changes value in the second tag. The issue is it doesn't change anything in the FX and the the number changes between the value I set and a random number. Also for the hammer offer but I have a couple of my own.



Thanks
Kevin

Do you feel the hate yet?
I hate Modbus RTU and Modbus TCP because few implement it correctly.
Keven, you have not provided much information. You should tell use what you have sent and what you have seen arrive. You should first try sending hex numbers like 1234H. The numbers should arrive as 1234H or 3412H. This will tell us if the is an endian problem. If you only have and endian problem, that is easy to fix. If you get garbage then your serial port probably isn't set up correctly.


Are you using the RTS and CTS lines? Even if the serial port can send and receive 115.2Kbps that doesn't mean the PLC or DSPSX can process data at that rate.


Modbus RTU is very timing dependent. The end of a pack is determine by not receiving a character for 3.5 character times. This means a gap of more than 3.5 character times will start a new packet so the sender must be able to send characters one after the other without delay. There cannot be a gap of 1.5 characters. How long is 1.5 characters are 115.2Kbps. How is this time measured? The answer isn't. Modern serial chips have 16 byte buffers but the buffer must be filled at frequent intervals to ensure there are no gaps between characters.

See the section on RTU framming. Few devices implement the specification correctly.

http://modbus.org/docs/PI_MBUS_300.pdf


I have go ape ***** nuts arguing with other companies that think just because they are big they are right.

http://www.plctalk.net/qanda/showpost.php?p=820279&postcount=10


Even our old motion controllers used DMA so they could keep up with the data flow. Few devices are implemented like that.

Peter after reading your answer I tried changing the baud rate and what does seem to work is if the FX is set to 19200 and the Red Lion is set to 115200 then things kind of work. I set up TagA to send to 40001 and then 400001 send to TagB. When I entered and value say 1234 into TagA it came up as 1234 in TagB but then would change to another number then back to 1234. It didn't matter if I changed 400001 to another address did the same thing. Changed the Red Lion baud to 115200 and then it worked. Now the only issue is I have no idea where it is being sent to in the FX. I have sent unique numbers and can not find them in the memory anywhere. I really realy hate Modbus and that is why I bought the DSPSX because I asked them if they could communicate with an FX and they said yes. I guess one more company to cross of the list. This is from Red Lion tech supports last email


[FONT=&quot]We have hundreds of protocols and unfortunately writing how to's for every plc companies release that use that protocol isn't something we've been able to keep up with. Sorry its been upsetting for you[/FONT]






Thanks
Kevin

klauricella said:

I really realy hate Modbus

Click to expand...

Me too, but it is because no one implements Modbus RTU correctly.


I have always prefer Rockwell's DF1 because it isn't timing dependent and can be full duplex. The only down side of DF1 is that it is only a data link layer so there is no definition of what is in the packet.

and that is why I bought the DSPSX because I asked them if they could communicate with an FX and they said yes.

Click to expand...

I bet it can if the Mitsubushi PLC can. So far you haven't established that the Mitsubishi PLC can use Modbus RTU. Back in the dark ages I would use a serial port data analyzer to monitor the data going back and forth. I would get to the bottom of the problem quickly. I could also use a scope to check for parities and start and stop bits.
I never use Modbus RTU though because at that time there were no Modbus RTU libraries or Mitsubishi serial cards for a FX2N. You do know that the

I guess one more company to cross of the list. This is from Red Lion tech supports last email


[FONT=&quot]We have hundreds of protocols and unfortunately writing how to's for every plc companies release that use that protocol isn't something we've been able to keep up with. Sorry its been upsetting for you[/FONT]

Click to expand...

I would side with Red Lion on this one. Are you claiming that Red Lion doesn't have a working Modbus RTU? If the Red Lion is sending out the correct data then it is the Mitsubishi's fault. I would blame Mitsubishi. It seems that Mitsubishi changes the protocol for every series of PLC.



So here is a question. Have your tried communicating between the DSPSX and a PC setup as a slave or master? There is plenty of free software out there for Modbus RTU. Have you done the same between a PC and the Mitsubishi?



One of our best distributors is in South Korea. They use Mitsubishi PLCs. I have had nothing but frustration getting Ethernet to work with Mitsubishi PLCs. Why am I doing it? Because our customers and distributors can't make it work but when they do work and they are fast.



I don't think you have gone about this correctly. I don't think the forum has asked the right questions.



You aren't the only one.

http://forums.mrplc.com/index.php?/topic/20120-fx3u-as-modbus-slave/