Big question ..HC11

There is no direct way. You must use the stack or a temporary variable. PSHA PULX - or - STA xx LDX xx

PSHA CLRA PSHA PULX

or similar

Will cause less angst at the next RTS.

Cheers, Alf snipped-for-privacy@remove.the.obvious.ieee.org

Thanks guys.

A is 8 bits and X is 16 bits. Assuming you want A in the least significant 8 bits of X then one way is:

PSHA CLRA PSHA PULX

which looses the content of A or

PSHA PSHA CLRA PSHA PULX PULA

which perserves A. Another way is

TAB CLRA XGDX

moves A into B (low 16 bits of D) and clears A (hi 16 bits of D) then exchanges D and X. This clobbers B.

Or use load and store instructions to a scratch location.

Many ways to skin this cat.

Dave Rooney

Or what you more often want to do:

PSHB PSHA PULX

I'd forgotten that X is 16 bits. Must have been in 6502 mode. *sigh*