please dont rip this site

Mike Harrison says:

While we're on the subject of neat little routines etc...

This code sends a byte at 115.2Kbaud
With a 4.096MHZ xtal, error is about 1.25% (near enough),
with 4.000MHz, 4.55% (marginal).

Data is non-inverted (i.e can be fed straight to PC)

txbyte
	mov	temp, W
	mov	W, #10	; 1 start + 8 data + 1 stop
	mov	cnt, W
	clrb	C	;start bit
	mov	W, Rb
txloop
	and	W, #0ff-(1<	;<seroutbit)
	sb	C
	or	W, #1<	;<seroutbit
	mov	Rb, W
  sec
	rr	temp	; carry shifted in as stop bit
	decsz	cnt
	jmp	txloop
	ret

Incidentally It's also possible to do 115K2 bit-bashed reception at 4.096MHz, by generating an INT interrupt off the startbit edge, and grabbbing all the data bits within the int code. Context save/restore overheads mean there's only a couple of cycles available to the foreground task if data is streaming in continuously!


file: /Techref/scenix/lib/io/osi2/serial/rs232at115kbps_sx.htm, 1KB, , updated: 2013/7/23 10:40, local time: 2022/7/5 15:39,
TOP NEW HELP FIND: 
3.235.78.122:LOG IN

 ©2022 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.massmind.org/techref/scenix/lib/io/osi2/serial/rs232at115kbps_sx.htm"> Mike Harrisons 115.2kBaud with a 4.096Mhz crystal</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?

 

Welcome to massmind.org!

 

Welcome to www.massmind.org!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

  .