Merge Two Integers

I will be using a PLC 5/80E with a Rice Lake 920i weigh scale on remote IO. Looking at the 920i Remote IO card manual, the device sends me back the weight split up as a 16 bit integer and then the first 4 bits of the next integer, making it 20 bits long. How do I combine the two integers, for example into a floating point register, so that I can work with the correct weight?

Hopefully this all makes sense. Help is much appreciated

Do you know what the format will be? If the first integer is whole number and second integer the decimal all you need to do is add them and store them in a floating point. If you are getting a whole number that is 20 bits move the 16bit integer to a floating point register and multiply by 1000 then add in the 2nd integer. It all depends on the format of the number you expect to receive.

multiply by 1000

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He said 4 BITS, not 4 DIGITS

It should probably be - multiply by 16

B Fix said:

I will be using a PLC 5/80E with a Rice Lake 920i weigh scale on remote IO. Looking at the 920i Remote IO card manual, the device sends me back the weight split up as a 16 bit integer and then the first 4 bits of the next integer, making it 20 bits long. How do I combine the two integers, for example into a floating point register, so that I can work with the correct weight?

Hopefully this all makes sense. Help is much appreciated

Click to expand...

I happen to have code to do this in RSLogix5000 for the Rice Lake scales over RIO. I pretty much copied/pasted it from Rice Lake's website. They have code snippet to do what you want on their site.

EDIT: Well it looks like you now have to buy the RIO manual for $35. What a crock. Call your distributor and they should be able to get you the manual which has the code examples in it, or if you have access to RSLogix5000, I can send you mine as an example.

Thanks for the help.

I did find a way to merge the two into one 20 bit integer. I just used the 2^xx power for each bit and added them together into one float.

robertmee, do you happen to have a link to where you found the sample code? I looked all over there website and was unable to find anything.

Use a two BTD's into the same floating point word. 1st BTD moves the 1st integer from bit 0 to bit 0 of the floating point register. The second BTD moves the data from the second integer starting at bit 0 to the destination of of bit 16 of the floating point integer. It in the RA knowledgbase somewhere.

B Fix said:

Thanks for the help.

I did find a way to merge the two into one 20 bit integer. I just used the 2^xx power for each bit and added them together into one float.

robertmee, do you happen to have a link to where you found the sample code? I looked all over there website and was unable to find anything.

Click to expand...

See my edit in the previous post....I couldn't find it any longer either.