Get feet and inch from total inches

I have a scaled analog input in a micrologix 1200. I can get total feet and total inches. What I am trying to do is display is feet and inch. so for example i want to display 8' 4". if I have 100 inches I can divide by 12 and get 8.33333. how do i get to the next step and get the to derive the inch fro 8.3333. by the way I scales the input to 16ths

Capman said:

I have a scaled analog input in a micrologix 1200. I can get total feet and total inches. What I am trying to do is display is feet and inch. so for example i want to display 8' 4". if I have 100 inches I can divide by 12 and get 8.33333. how do i get to the next step and get the to derive the inch fro 8.3333. by the way I scales the input to 16ths

Click to expand...

Integer Division will return Feet
Modulo will return inches

Given 12 Inches per Foot
100 INT DIV 12 = 8
100 MOD 12 = 4

i did not think the 1200 had a modulus function .. i will look again

forgot about that .. no CPT

I guess that basic math will have to work.
Since your resolution is 1/16 you will have a bit more work, but for INCH

aa is FEET
bb is intermediate
cc is INCH
100 INT DIV 12 = aa (aa = 8)
aa * 12 = bb (bb = 96)
100 - bb = cc (cc = 4)

If you can separate the fractional, then you can do the above., and add the fractional back to the display.

thanks

MicroLogix does not have Modulus.

I believe if you do an integer divide, it will round the result. A workaround for this is to put the value into a Float register, do the divide, subtract 0.5, then move it back into an integer. This will basically give you the truncated value of the divide. Then, multiply the result by the original divisor, and subtract that from the original value and that will be your modulus.

So for example:
100 >> 100.0 (make it a float)
100.0 / 12.0 = 8.333
8.333 - 0.5 = 7.833
7.833 >> 8 (move back to integer; this is your feet)
8 * 12 = 96
100 - 96 = 4 (this is your inches)

Check this in the help file on the 'DIV' instruction

The unrounded quotient is placed in the most significant word of the math register; the remainder is placed in the least significant word.

Click to expand...

And this from the instruction manual

Use the DIV instruction to divide one value by another value (Source A/ Source B) and place the result in the Destination. If the Sources are single words and the Destination is directly addressed to S:13 (math register), then the quotient is stored in S:14 and the remainder is stored in S:13. If long words are used, then the results are rounded.

Click to expand...

(Note: my underlining)

See if you get the result you need.