please dont rip this site

Shift by 4 bits at a time

Code:

Alex Davies of Ace Electronics Engineering Says:

You can save 1 word per byte on the above by using XOR swaps with W as a carry register. ie, to shift to the left by a nibble:

SWAPF TEMP0, W
MOVWF TEMP0
ANDLW 0x0F
XORWF TEMP0, F

SWAPF TEMP1, F
XORWF TEMP1, F
XORWF TEMP1, W
ANDLW 0x0F
XORWF TEMP1, F

SWAPF TEMP2, F
XORWF TEMP2, F
XORWF TEMP2, W
ANDLW 0x0F
XORWF TEMP2, F

...

(untested)
+
file: /Techref/microchip/math/bit/shift4.htm, 1KB, , updated: 2010/3/1 16:52, local time: 2024/11/5 17:27, owner: mark_jeronimus-gmail-,
TOP NEW HELP FIND: 
3.231.219.178:LOG IN
©2024 PLEASE DON'T RIP! THIS SITE CLOSES OCT 28, 2024 SO LONG AND THANKS FOR ALL THE FISH!

 ©2024 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions?
Please DO link to this page! Digg it! / MAKE!

<A HREF="http://www.piclist.com/techref/microchip/math/bit/shift4.htm"> Shift by 4 bits at a time</A>

After you find an appropriate page, you are invited to your to this massmind site! (posts will be visible only to you before review) Just type a nice message (short messages are blocked as spam) in the box and press the Post button. (HTML welcomed, but not the <A tag: Instead, use the link box to link to another page. A tutorial is available Members can login to post directly, become page editors, and be credited for their posts.


Link? Put it here: 
if you want a response, please enter your email address: 
Attn spammers: All posts are reviewed before being made visible to anyone other than the poster.
Did you find what you needed?

  PICList 2024 contributors:
o List host: MIT, Site host massmind.org, Top posters @none found
- Page Editors: James Newton, David Cary, and YOU!
* Roman Black of Black Robotics donates from sales of Linistep stepper controller kits.
* Ashley Roll of Digital Nemesis donates from sales of RCL-1 RS232 to TTL converters.
* Monthly Subscribers: Gregg Rew. on-going support is MOST appreciated!
* Contributors: Richard Seriani, Sr.
 

Welcome to www.piclist.com!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  .