High Word, Low Word Data

[plcjunior]

I have an application where i am using an A/B plc with an ultra 3000 servo drive. I am sending data from my plc to the drive for indexed positions but the drive is requesting the data in seperate high and low words. Can anybody assist me on how to go about doing this to.

 

[NWBeaver]

The high and low word arrangement typically wants to have the data value divided such as this:

Example data value 4095
The high word would be 4 (4095 / 1000)
and the low word would be 95 (remainder)

You basically divide the value by 1000, and put the results
in two separate words.

Depending on your application the high word may be the most significant or the least significant.

 

[plcjunior]

So NWBeaver what if the data value being sent was 250,000. If you send this value would it still have to be divided by 1000.

high word being 250 (250,000/1000)
and low word being 0

What is the maximum data value that can be divisable by 1000 or that can be stored in the high and low word.
Would it be 65 536 x 1000 = 65,536,000. Cause if you divide 65,536,000 by 1000 then that gives you 65,536 which is the maximum value that can be in one word. Is this right.

Thanks for the help

 

[NWBeaver]

Yes, 250,000 would be 250 and 0.
The applications that I have seen were capable of values up to 999,999, but in theory I suppose you could go much higher as you suggest.
The high word, low word idea just allows a value greater 65,536 to be passed, as a way of getting around the limitations of a 16 bit integer, since not all systems can handle 32 bit integers.

 

[plcjunior]

NWBeaver thanks for the help. much appreciated!!