Bit manipulation

On Wed, 28 Sep 2005 08:26:43 -0500, "Dejan" wrote in comp.arch.embedded:

I'll answer your question, if you answer one of mine! My question is: why do people post to usenet through web sites like embeddedrelated.com and dsprelated.com instead of using a newsreader and posting directly?

In any case, the Atmel ARM microcontrollers contain hardware in the PIO and UPIO interfaces themselves that does this in hardware.

Each peripheral register has corresponding "_SODR" and "_CODR" registers. To turn one or more output bits, write a word with the corresponding bits turned on, and the other bits turned off, to the "SODR" (Set Output Data Register). To turn off one or more bits, write a word with the corresponding bits turned on, and the other bits turned off, to the corresponding "CODR" (Clear Output Data Register).

When you write to either of these registers, where you write a 1 bit the corresponding output pin is set to 1 or cleared to 0, if it is programmed as an output. Any bits that are 0 in the word you write do not change the level of the corresponding output pin.

..and the new Philips LPC210x devices, put the 'Port SFR's mapped onto the Faster Local BUS, not the APB, and they claim 17.5MHz toggle rate - see

- but to answer your original question, no, the ARMs lack inherent BIT opcodes/BIT mapped SFRs, and so this band-aid HW design overcomes that shortcomming - it was, after all, never designed as an embedded microcontroller but as a CPU.

-jg

Hi Jack, thanks, but to answer your Question. I have no possibility to use direct some newsreader beacouse of our Proxy. It blocks that service. So I need to use some work out, in this case WWW Newsgroup interface.

Thanks Jim, that's what I wanted to know. I'm a little bit disappoint of ARM as not design to be an embedded microcontroller.

Hi Jack, thanks, but to answer your Question. I have no possibility to use direct some newsreader because of our Proxy. It blocks that service. So I need to use some work out, in this case WWW Newsgroup interface.

There are usenet servers that can be over ports normally reserved for http. Specifically for people who normally only have the common ports for http open.

Regards Anton Erasmus