Instruction Set Summary, with limitations ?

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Has anybody written up a copy of the AVR instruction set that makes the limitations more obvious?
I mean, which instructions are good for all 32 register vs which are good for only 16-32 vs which are x/y/z only, which IO instructions are good for 32 or 64 registers, and so on...

Thanks
WestfW

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I just took a colored pencil and underlined the few instructions.

Klaus
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Look at: www.megausb.de (German)
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Well, there are some "patterns" as to which instructions that has limitations on which registers that can be used:

Instructions for setting/clearing bits in general purpose registers:
CBR, SBR, SER

Instructions with immediate operands:
ADIW, ANDI, CPI, ORI, SBCI, SBWI, SUBI

Multiply instructions (on supported devices):
FMUL, FMULS, FMULSU, MULSU, MULS

Word operations where certain register alignment is needed, eg. MOVW.

This came from a five-minute browse through the instruction set document. I might have missed out on some, but the point is that it is not completely arbitrary which instructions have these limitations or not.

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