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RE: [AVR-Chat] Re: ISP Port Restictions

2009-10-07 by Tim Mitchell

----Original Message----

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From: AVR-Chat@yahoogroups.com
[mailto:AVR-Chat@yahoogroups.com] On Behalf Of
andrew.mathison Sent: 07 October 2009 10:40 To:
AVR-Chat@yahoogroups.com Subject: [AVR-Chat] Re: ISP Port
Restictions 

> May I try and warn you that the resistors you are
> contemplating using, could allow more current than many
> PPorts can supply....  
> Please check on the web yourself, but generally speaking,
> you cannot rely on sourcing more than 2.5ma or sinking
> more than 24ma. In fact some cannot even sink that much.  
> 
> A place to start is here:-
> http://www.lvr.com/files/ibmlpt.txt
> 
> If you are just using a plug in LPT: card in a PC,
> blowing it is of almost no concern (I would NOT use the
> mainboard printer port for anything other than a printer
> as its part of the mainboard chip set nowadays!!) as a
> cheap replacement will get you up and running again.    
> 

Yes, really I would recommend buying the Atmel AVR-ISP which is a USB
device costing about $30 / 25 euro (depends where you are in the world).

Saves a lot of messing around and the danger of blowing up your PC.

-- 
Tim Mitchell

Re: ISP Port Restictions

2009-10-07 by _wsw_

--- In AVR-Chat@yahoogroups.com, "Tim Mitchell" <tim@...> wrote:
>
> Yes, really I would recommend buying the Atmel AVR-ISP which is a USB
> device costing about $30 / 25 euro (depends where you are in the world).
> 
> Saves a lot of messing around and the danger of blowing up your PC.

...and will even be updated regularily by Atmel in order to program new chips. Just try to find some of this 'quick and dirty adapters' that can program a XMEGA (what the AVRISP mk-II can since more than half a year)...

Stefan

Re: ISP Port Restictions

2009-10-08 by granz_consult

Tim,

Thanks for your input - this is for an Ultra-Low cost robot for use with kids in a club or homeschool environment.  Part of the appeal of this is that the programming cable can be built for less than $5.00.  $30.00 is not a lot of money, but when the 'bot itself with the programming cable is running about $30.00, that would almost double the cost.

The 2313 has enough I/O that it will do the job (introducing kids to computers/control systems/robotics) even if I dedicate those 3 lines to the programming cable exclusively.

Thanks for all of you who helped out with this.

Art

--- In AVR-Chat@yahoogroups.com, "Tim Mitchell" <tim@...> wrote:

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>
> ----Original Message----
> From: AVR-Chat@yahoogroups.com
> [mailto:AVR-Chat@yahoogroups.com] On Behalf Of
> andrew.mathison Sent: 07 October 2009 10:40 To:
> AVR-Chat@yahoogroups.com Subject: [AVR-Chat] Re: ISP Port
> Restictions 
> 
> > May I try and warn you that the resistors you are
> > contemplating using, could allow more current than many
> > PPorts can supply....  
> > Please check on the web yourself, but generally speaking,
> > you cannot rely on sourcing more than 2.5ma or sinking
> > more than 24ma. In fact some cannot even sink that much.  
> > 
> > A place to start is here:-
> > http://www.lvr.com/files/ibmlpt.txt
> > 
> > If you are just using a plug in LPT: card in a PC,
> > blowing it is of almost no concern (I would NOT use the
> > mainboard printer port for anything other than a printer
> > as its part of the mainboard chip set nowadays!!) as a
> > cheap replacement will get you up and running again.    
> > 
> 
> Yes, really I would recommend buying the Atmel AVR-ISP which is a USB
> device costing about $30 / 25 euro (depends where you are in the world).
> 
> Saves a lot of messing around and the danger of blowing up your PC.
> 
> -- 
> Tim Mitchell
>