15 posts in this topic

Hi,

I keep getting an error that project is in binary mode and plc is in BCD mode.  Wont let me change either. I must be trying in the wrong place...please point me to where i can change this in the PLC.  

I am getting an error in my RXDU with a Honeywell barcode reader, on one machine, I am thinking it is related.  

thanks for any help. 

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PLC|Properties

PLC Properties.jpg

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I always tick execute timer/counter as binary - this requires a download to the PLC and will muck up ant BCD timers and counters that will have to be re-orograme as TIMX and CNTX though instead of TIM and CNT.

I fail to see how that could be causing an error with RXDU though - unrelated.

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I agree BobB, the error only means that you either have the box checked and tried to use a TIM or CNT type instruction, or you do not have it checked and tried to use a TIMX or CNTX instruction.  If you are using a PLC that you can choose this option and you are starting from scratch, always check the box and use TIMX and CNTX instructions.  If you have both TIMX and CNTX / TIM and CNT instructions in your program, it does not matter if the box is checked, you will get the error.  With some PLCs you have to choose one or the other, not both.

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Thanks guys. box is checked - two PLC's work, two dont.  Identical programs in them.  Still scratching my head as to why RXDU does not work on two machines.

Am only using TIMX, no problem with timers.

The yellow LED on SCU41V1 (RD2)  stays lit on the two machines that don't work.  All honeywell barcode readers work on the same two machines, but the rxdu does not work on the other two machines - so not an external hardware issue. Bar code connected to port 2, unit 3.

1594.06 (completion flag) stays as open contact on ladder, not letting rxdu have a chance.

A202.02 (in series with 1594.06) is closed most of the time - seems fine.

  Have swapped around SCU41and connectors separately and issue stays with the controller.  I am thinking I have a hardware issue with two of the four controllers? 

I admit, my programming is beginner level - so I keep thinking that is the problem, but my troubleshooting leads me to the controller itself.

The ascii text it is trying to read is something like ID12345 or ID12346 etc.  Sometimes it will be SN(for serial number) then 5 to 7 numerals.


Takes D200 through D204 in space, although up to D209 is left available for longer numbers.  As I scan new codes, the working plc's basically replace the old ID code with the new. 

On the non working machines, it adds to the total # of bytes to transmit. 

Instead of D200 to D204 reading  "ID12345",  I had "IM0"  ascii or "494D30" Hex.

 

 

screengrab1.PNG.112eed61ffc710ea68b0d781

Edited by indepthmarine
clarification

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Are the unit numbers for the SCU41 the same?

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RXDU.jpg

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Quote

Instead of D200 to D204 reading  "ID12345",  I had "IM0"  ascii or "494D30" Hex

The Reception Completed Flag (note 1) will turn ON when the number of bytes specified by the allocated DM Setup Area has been received. When the

Reception Completed Flag turns ON, the number of bytes in the Reception Counter (note 2) will have the same value as the number of receive bytes

specified in the allocated DM Setup Area. If more bytes are received than specified, the Reception Overflow Flag (note 3) will turn ON.

 

The reason 1594.06 does not turn back on is that it is waiting for the reception of another three bytes. I would check the Honeywell book for what "IM0" indicates.

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RXDU

Reads the specified number of bytes of data from one of the Serial Communications Unit’s serial ports.

(The Serial Communications Unit must be Ver. 1.2 or later).

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Thanks again,.  

 

Jay, so to specify directly for unit 3, serial port 2 I would put 

C = 0000

C+1 = 00 (81 + 4X3)  o 008D ? 

I will check if it the serial port unit is  V1.2 or later when I get to the office.

Thanks again!

 

Edited by indepthmarine

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Jay, so to specify directly for unit 3, serial port 2 I would put 

C = 0000

C+1 = 00 (81 + 4X3)  o 008D ? 

You were correct with C+1=2213

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It is SCU41 V1  Version 1.3

DM30198/30199 is COFA A808  which to me is 192 250 168 08 instead of 192 168 250 08

is this normal?

 

Do I need to set the IP address beneath the "Broadcast" box as well?  and subnet mask?  I had it there, with 255 255 255 0 as subnet, but had a blinking erh led.  It is not blinking now...

57622fed54f16_IPsettings.PNG.6cee324d9a1576230eff1915_IOtable.PNG.ec679c8d1b9826

 

Edited by indepthmarine

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Is there a place where I can monitor the raw data string  coming into SCU41V1  Unit 3 port 2?

That way I could see what changes when I read it to the CPU...

 

Yes, the unit numbers for the SC41 is the same.  Setup on all 4 machines is the same, program is the same.  

I have since started from scratch with one PLC, hopefully can clean up the program and find my errors. 

Edited by indepthmarine

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No.  You need serial snooper software.

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Thank you Jay, Michael and Bob! 

turns out it was a poor data  ground to pin 9 via the circular connectors on the case bulkhead.   I had measured low ohms originally, and tested both wiring harnesses in both machines, error stayed with one machine.

Was confident in the wiring, not so much in the programming.  Oops. 

It is working in both machines now - but I am sharpening up some sloppy programming, so not a bad thing.

Thanks again!

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