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General Category => General Discussion => Topic started by: David Emmerich on June 30, 2009, 12:40:02 PM

Title: Cmore to 260 comm
Post by: David Emmerich on June 30, 2009, 12:40:02 PM

Help me!!! My head is not working today.....How do I get a 260 to read (and understand) the value entered on a cmore panel thumbwheel? The address on the thumbwheel is V3000, and I have put a LD V3000 in the program, but it does not show up....


David

Title: Re: Cmore to 260 comm
Post by: b_carlton on June 30, 2009, 01:04:13 PM

1. Does V3000 change at all? Can you have Directsoft and the CMore connected at the same time so you can observe the operation?

2. Is the CMore communicating correctly? Is it affecting anything in the 260?

3. To clairify, you say 'the address on the thumbwheel'. This means the address for the tag is V3000, correct?

4. Could something in the program be overwriting V3000?

5. When yoou say 'does not show up', where are you expecting something to 'show up'?

Title: Re: Cmore to 260 comm
Post by: David Emmerich on June 30, 2009, 01:48:09 PM

Hi Bernie, Yes, the address is set to v3000 on both the AD260 and the Cmore...the Cmore is reading and sending to the 260...the thumbwheels are sending a BCD back, shoudn't it be an integer?...and do I need to use a LDD instad of a LD?....my head is just not working right today....

Thanks for your help!!!!!

David

Title: Re: Cmore to 260 comm
Post by: b_carlton on June 30, 2009, 03:02:15 PM

Refer to my #5 question. The current value of the location will not show up in a LD command even when online. You can open a dataview, fill it with V3000 and make sure to turn on the status, to see what value is stored there dynamically.

The format of the number is up to your project.

Please refer to my intro on AD http://www.theplcguy.com/ABtoAD/Introduction.htm (http://www.theplcguy.com/ABtoAD/Introduction.htm) especially the section on numeric types. Note that the BCD or standard integer form can occupy one location (which would nead a LD command) or in a double word (32 bits) format which would require an LDD command. The LD commands don't care what the format of the number is. They either bring 16 bits into the accumulator (LD) or 32 bits consisting of the referenced 'V' location and the following one (LDD). By the way this is a 'little-endian" storage whic means that for a 32 bit value the least significant 16 bits are in the lower numbered 'V' register.