18 posts in this topic

I'm working on a project that reads an RF - TAG via RS232. It uses the G.INPUT command. I need some help to see if I understand clearly how it works. Now it reads a maximum of 16 digits but in the future i want to pass it to 32 bits. The command line is

|G.INPUT    U5    D6500    D6800    M7922|

If I understood correctly I load in D6500 either 1 or 2 to tell it which channel to read from. It stores the 16 digits in words starting from D6800 and goes on till D6815 if I am correct. My questions are:

- did I understand correctly how to use the command and is there anything else i need to take care of while using it?

- do I need to do additional settings to it in order to read 32 digits or does it automatically read (if the RF reader is compatible with 32 digits)?

Thank you,

Andrei

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After what I can read from the instruction help, you are correct. I would guess that it can handle 32 digits too (or more if needed). You can simply test it, connect a computer and send strings (if you don't have a RFID reader just use your computer as a string-sender)... Then you can test all you want and see the results.

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Good Idea. I'm receiving the HW to test everything next week and I'll get a PC from a coworker with a small program to send me a 32 digit string to see if I receive it all. It reads only when the input condition of this command is met right? Or does it read continuously?

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I made a print screen of the existing screen. I don't understand why the original coder did it like this. Do you have any ideas?

1.jpg

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 @kaare_t I also have before reading from the RF ID reader a couple of commands that i'm not sure about. 

TO      U5     H93     K0      K1

TO      U5     H133     K0      K1

TO      U5     H93     K0      K1

TOP    U5    H0A5     H0A0D    K1

TOP    U5    H145     H0A0D    K1

TOP    U5    H0A5     H0A0D    K1

TOP    U5    H0A5     H0D    K1

TOP    U5    H145     H0D    K1

 

Can you help me. I've been searching the QJ71C24-R2 Manual and no luck :(

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You should read some informational documents soon, e.g. like the manual for the C24 since you obviously have a lot of questions...

About the code above: What is it that is unclear? And P.S. It looks like the programmer already accounted for up to 70 bytes or words (depending on the C24 card config).

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Just now, Andrei Blagaila said:

@kaare_t I also have before reading from the RF ID reader a couple of commands that i'm not sure about. 

TO      U5     H93     K0      K1

TO      U5     H133     K0      K1

TO      U5     H93     K0      K1

TOP    U5    H0A5     H0A0D    K1

TOP    U5    H145     H0A0D    K1

TOP    U5    H0A5     H0A0D    K1

TOP    U5    H0A5     H0D    K1

TOP    U5    H145     H0D    K1

 

Can you help me. I've been searching the QJ71C24-R2 Manual and no luck :(

You should check out the C24 manual and the buffer memories (BFM). These are all moving values into their respective BFMs. E.g.:
TO U5 H93 K0 K1 are TO (write to), U5 (module 5), H93 (BFM 93hex) K0 (the data to be written) K1 (the number of words to write from the first word to be written)

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Just now, Andrei Blagaila said:

Where did you see that he has accounted for up to 70 Bytes?

As I wrote, it looks like it. Look at the "MOVP K70 D6503" instruction where the comment and most likely control word corresponds with "70". You have to check in the manual if the 4th word is the max allowable devices to read, just to be sure.

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Thank you for your help. I'll search a bit more in the user manual for the C24 to try to understand what the BFMs stand for.

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BFM = Buffer memory. It's simply the internal devices (words) in the IO cards of the PLC's. It's just a different word for devices used in modules instead of D-devices, L-devices, M-devices and so on... The BFMs are different from module to module (e.g. C24 cards have one list of BFM while E71 have a different list).

Since the reside in the modules most of them are for system parameters, some are ReadWrite and some are ReadOnly. That is why you have to check the manual, to figure out what the specific devices do, why they are written to, and what data is written.

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I've been looking over the manual and cannot find 145H anywhere. I found H0A5 or better A5H that's "Receive Complete Code" but cannot find the list you are talking about. Can you help me because it it possible that I'm not looking in the right place.

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If you've found A5H/H0A5 then you should be able to find 145H/H145 too. They are the same type, only channel1 and channel2 (see attached picture from the manual).

145.png

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SH-080006.

"User's manual (Basic) Communication Modules QJ71C24N(-R2/-R4), QJ71C24(-R2)".

You can find it or a similar manual in the download section at Mitsu. Mine is quite old I think (haven't checked for new versions of my manual for ages)...

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So now I understand a bit more about those addresses. Unfortunately now I have another issue that is not clear. So in the commmand:

G.INPUT   U5    D6500   D6800   M5870 

D6500 is not only the channel but is also the name of the first word that I send to C24? You said that D6503 is also send because it sets the 70 word maximum data to be received. So that means I send it right? I'm relatively new to PLC's with communication protocols (i used simply HW structures untill now) and I'm struggling to understand how everything works. Can you help me out a bit based on the print screens I sent in the first post to explain how it's supposed to work? I'd really appreciate it. thanks

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It took me all day to find this stupid manual but now I understand that S0 S1 S2 and S3 are actually sent using G.INPUT and starting from D1 it stores the up to x words and after that they activate the memory M because the read was complete. I'm gonna hopefully test with a PC once the HW arrives. Thank you a lot for you help and patience. 

1.jpg

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