data TYPE

Hi everyone,

Can anyone explain further what are the differences of the following:

1. signed_int_16
2. unsigned_int_16
3. unsigned_int_32
4. signed_int_32
5. BCD_int_16
6. BCD_int_32
7. Floating_PT_32


Could someone just give me a rough idea?
I'm converting an HMI program and I have come accross with these selections with the data types after the address strings. What are the differences with these data and how would it affect the program if I select the wrong one?

The old program I'm trying to convert is showing SIGNED DECIMAL and UNSIGNED DECIMAL but the new software I'm using is showing only the above 7 SELECTIONS. Which one corresponds to the signed and unsigned decimal?

Cheers,
Fyodor

It looks like you are working on an EZTouch touchscreen so...

This document may be of some help: http://support.automationdirect.com/docs/an-misc-013.pdf

It shows how these data formats are decoded and relate to each other. Hopefully it helps.

What you need is a good introduction to binary number systems.

The last digit of each description is the number of bits in the data type. The rest of the type describes how those bits are going to be interpreted. Usually a signed 16 bit number has a range of -32767 to +32768 while unsigned 16 bit numbers have a range of 0 to 65536. Note that the top end of this range is 2^16. So, extrapolate for 32 bit ints.


For the BCD stuff you can check out this link:
http://www.evergreen.edu/biophysics/technotes/program/bcd.htm

It looks like you need to know whether the information is in packed or unpacked BCD format.

Floating point i a way to represent approximations of real numbers in the inherintly digital world of computers.

I susptect you'll be using signed_int_16 and unsigned_int_16 in your application but the word "decimal" is ambiguous and should be researched to ensure it referes to 16 bit numbers.

Maybe if you post the name of the HMI other's will know more.

Good Luck

Thanks guys, I got the documents and will read them later when I get home. I had a quick look and it looks like it does have the answer to my query. This is of great help, BTW, it is a Uticor HMI I'm trying to program from the old PGI100 model to the new powerpanels.

Cheers,
Fyodor