Re: A86: FindPixel
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Re: A86: FindPixel
On Wed, 6 May 1998, Dux Gregis wrote:
>
> It moves the bits 0, 1, 2 and 3 of (hl) to bits 4, 5, 6, and 7 of (hl).
> It also moves the high bits to where the low one used to be.
>
Not exactly. The A register is involved, too. Here's my cheesy ASCII
version of the picture in the Z80 databook:
RLD +--------------------+
| |
| V
+-----+-----+ +-----+-----+
A | 7-4 | 3-0 | (HL) | 7-4 | 3-0 |
+-----+-----+ +-----+-----+
^ | ^ |
| | | |
+-------------+ +----+
RRD +-------------+ +----+
| | | |
| V | V
+-----+-----+ +-----+-----+
A | 7-4 | 3-0 | (HL) | 7-4 | 3-0 |
+-----+-----+ +-----+-----+
^ |
| |
+--------------------+
--------
Dan Eble (mailto:eble@cis.ohio-state.edu)
(http://www.cis.ohio-state.edu/~eble)
"Behold, how great a matter a little fire kindleth!" -- James 3:5
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