AVR-Chat

Hello Micah,

Though not an Atmel AVR device, I've seen a case where is an unconnected
serial port header was picking up electromagnetic interference in a
harsh industrial environment. This was a susceptibility case, but  in
the final product i'll consider a second hardware checkpoint before
flashing the eeprom with the incoming bytes :)

If you want to feel safe, put a rise time limiting series resistor close
to the uC's pin, it will help you limit the frequency content of the
net. It's not just the header but also the pcb trace can act as an
antenna and radiate/pick up. Doing this also makes your power rails
inside the uC cleaner. Motorola HCS08 devices have for example
programmable rise time for the IO, you can select between strong/weak
etc. push/pull operation.


Regards

Murat Karadeniz
http://www.onlinefavbar.com/mukas/




-----Original Message-----
From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On
Behalf Of Micah Stevens
Sent: Wednesday, December 28, 2005 9:58 PM
To: AVR-Chat@yahoogroups.com
Subject: Re: [AVR-Chat] DebugWire question..



Wow, at 10Ghz, yes, I'd agree. I'll try it and hook up the spec an, and
see 
what I get I guess. Thanks for the reply, makes me feel better about it!

-Micah


On Wednesday 28 December 2005 8:48 am, Brian Dean wrote:
>  On Tue, Dec 27, 2005 at 09:59:53PM -0800, Micah Stevens wrote:  > 
> However, I need to use one pin of the serial interface(MOSI I think)  
> > as a PWM output. I'm concerned that during normal operation, any  > 
> sort of header would just turn into an antenna at the PWM  > 
> frequencies I'm using.
>
>  Unless you are PWM'ing on the order of around 10 GHz, I think you 
> will  be OK.
>
>  -Brian
>  --
>  Brian Dean
>  ATmega128 based MAVRIC controllers
>  http://www.bdmicro.com/
>
>
>
> SPONSORED LINKS
> Atmel avr   Microcontrollers   Intel microprocessors
>   Pic microcontrollers
>
>
> YAHOO! GROUPS LINKS
>
>
>  Visit your group "AVR-Chat" on the web.
>  
>  To unsubscribe from this group, send an email to:
>  AVR-Chat-unsubscribe@yahoogroups.com
>  
>  Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.



 
Yahoo! Groups Links