Assigning byte variable from a long/word value?

kwagner · 2022-01-04 20:47

I have some network stuff I'm doing as byte arrays, and I need to fill in some of them with values I'm getting from words. Do I need to bother doing the following:
a[0] := (b>>8)&$FF
a[1] := b&$FF
Or does it only copy the bottom 8 bits regardless, in which case the &$FF is wasted cycles?

JonnyMac · 2022-01-04 21:50

if a is an array of bytes, then any simple assignments to it will be truncated to 8 bits.

I double-checked with this bit of code:

pub run_test() | byte a[4], x, y

  bytefill(@a, 0, 4)                                            ' clear array to start

  repeat x from 0 to 3
    a[x] := $1234
    repeat y from 0 to 3
      term.fxhex(a[y], 2)
      term.tx(" ")
    term.tx(13)

This was the output:

kwagner · 2022-01-05 02:54

Thanks, that's great!

Assigning byte variable from a long/word value?

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