Please confirm NOP = 0x 0000_0011 ?

Algorithm development and general DSP issues

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Digital Larry
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Please confirm NOP = 0x 0000_0011 ?

Post by Digital Larry »

I'm working on making my program output Intel Hex directly.

Looks like when Spin IDE does this it fills space past the end of the explicit instructions with 0x0000_0011. However there is no reference to "NOP" giving its bit pattern in the ASM manual.

Thanks!
frank
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Post by frank »

I thought it was 0x0000000F which is an OR with all bits 0 so nothing changes.
Frank Thomson
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Digital Larry
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Post by Digital Larry »

Here's the section of Patch 0's generated hex (from Spin IDE) where it goes from having some instructions to all no-op or whatever.

:04005400400004A4C0
:04005800400002C69C
:04005C00000002E6B8
>>> right here <<<
:04006000000000118B
:040064000000001187
:040068000000001183
:04006C00000000117F

Last byte is the checksum. It really looks like 0x0000_0011 to me.

But then the pattern changes once we hit the transition to data for patch 1.

:0401F80000000011F2
:0401FC0000000011EE
>>> right here <<<
:0402000011000000E9
:0402040011000000E5
:0402080011000000E1

I'm guessing that's actually a bug because it only happens when you generate hex on a single program without the dev board attached, and save the hex.
Last edited by Digital Larry on Sun Jun 14, 2015 3:59 pm, edited 1 time in total.
Digital Larry
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Post by Digital Larry »

Looks like 0x 0000_0011 is equivalent to:

SKP 0,0

There are no bits set to match any condition, and in any case it was just skipping 0, which is to execute the next instruction. So I'd call that a NOP.
frank
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Post by frank »

Keith managed the guy doing the assembler so they may have changed it after telling me what it was. SKP 0,0 is fine as a NOP.
Frank Thomson
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Post by Sandrine »

I noticed that too the other day. It seems to only change on an 8 bit roll. I thought it had some deep dark purpose..
Is there a latin word for "Stage Fright"?
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