Bits, Bytes Words and Arrays

[Darrel Taylor]

6. How can I reference a WORD in a BYTE ARRAY?

Let's say that you have a WORD located at bytes 3 and 4 of a BYTE array, and Byte 3 is the LowByte. You can use the EXT (external) modifier to assign it to a WORD variable.


MyByteArray VAR BYTE[10]

MyWord VAR WORD EXT
@MyWord = _MyByteArray + 3

[khoog]

Thanks Darrel,

Your example will put the low byte into the array. How do I get the high byte in?

MyByteArray VAR BYTE[10]
MyWord.byte0 VAR MyByteArray[3]

or

MyByteArray VAR BYTE[10]
MyWord.byte1 VAR MyByteArray[3]

will work as well.

I can read in either the high or low byte, but not both of them.

[Darrel Taylor]

It creates an Aliased WORD variable, inside the BYTE array.

When you assign a value to the WORD variable, it puts both BYTEs in the array in a single operation.

MyWord = $1234

will make MyByteArray look like this

[00, 00, 00, 34, 12, 00, 00, 00, 00, 00]

HTH

[khoog]

Thanks again Darrel. That's almost too slick to be true. When you start throwing around those "@" signs it becomes a little mystical for me.

I will try it and let you know.

[shahidali55]

After searching the whole forum for an hour or so i stumbled upon this page.
Finally i can dynamically access bits of a variable. This has really helped me a lot.
Thank you Melanie .

[mtripoli]

Isn't this information in the PicBasic Pro Compiler doc's... something like "Variables", "Aliases", "Arrays" and so forth...?

Mike Tripoli

[Archangel]

Isn't this information in the PicBasic Pro Compiler doc's... something like "Variables", "Aliases", "Arrays" and so forth...?

Mike Tripoli

Probably most of it, Manuals and Data sheets are written by engineers, FOR engineers, and some of us NON engineers have a little trouble getting our heads around them, SO an experienced Advisor / Professor / Engineer / Guru / or even Lay person who knows, lending guidance is appreciated, and welcomed even if some of see it as too basic. You are new here, Welcome, Your statement tells me you might be really knowledgeable. I hope so, we can always use more people who are. I am not, but I help when I can. I learn something here nearly every time I come in. Every newbie can figure out a different way to "stall out" and I have seen some pretty unusual new ideas (that often do not work ) but they challenge me to think, and learn.
Again Welcome Mike Tripoli.