Lpc2000

I may have missed this if anyone mentioned it before, but if you're 
building that aren't going to be shipped to end users, a MAX232 runs 
fine at 3.3V.  You get +-6.6V out of the charge pump, instead of +-10V, 
but 6.6V is well within the RS-232 spec.  I used Sipex and Maxim parts 
all the time in this configuration for prototyping, or whipping up a 
quick RS232 interface to a logic level device.

    I know there was more in this thread, but my mail server swallowed 
it, so I apologize if this idea has already been mentioned.

    --jc

Robert Adsett wrote:

> At 10:45 AM 12/11/04 +0000, you wrote:
> >Unfortunately I cannot obtain any RS232 Driver for 3.3V, yes for 5V.
> >In My LPC board I have 5V, so I was thinking about adding some
> >transistor and convert the 3.3V from the LPC2106 to 5V and viceversa
> >for the RX pin. I know this is not the best solution, but I think it
> >could work. If not, what about making a Level shifter with
> >Transistors? Does anybody have a schematic, or can help me with this?
>
> In addition to all the pointers to 3V level convertors I would add;  Why
> not just use a 5V level convertor since you have the 5V available?  
> Run 5V
> to you level convertor and then hook it's Rx and Tx lines to the 
> micro.  If
> your level convertor is TTL compatible then it's inputs should match the
> drive output.  Check the VIH rating of your convertor.
>
>
> Robert
>
> " 'Freedom' has no meaning of itself.  There are always restrictions,
> be they legal, genetic, or physical.  If you don't believe me, try to
> chew a radio signal. "
>
>                          Kelvin Throop, III