Lpc2000

A trick I use:  Use an extra channel on the RS-232 driver to provide 
the negative voltage required for the LCD.  Just tie the 
corresponding input high to get ~-8V on the output.

Richard


--- In lpc2100@yahoogroups.com, "Leon Heller" <leon_heller@h...> 
wrote:
> 
> ----- Original Message ----- 
> From: "Lasse Madsen" <lm@h...>
> To: <lpc2100@yahoogroups.com>
> Sent: Thursday, December 18, 2003 8:41 AM
> Subject: [lpc2100] Hi all.
> 
> 
> > Hi everyone.
> >
> > I'm so pleased to find the LPC user group here on yahoo as i've 
been
> looking
> > for info about the LPC2106 for quite some time.
> >
> > Allow me to introduce my self.
> >
> > My name is Lasse Madsen im an electronics engineering apr. from 
Aalborg,
> > Denmark.
> > Im daily involved with Atmel AVR software development in C / Asm. 
I
> decided
> > to try the LPC series on an excisting AVR design to see if there 
where
> major
> > differences regarding speeds etc.
> >
> > I have the ARM Embedded Toolkit compiler as I've been using 
Samsung's
> B0X44
> > multimedia ARM processors I guess it should also work with the 
LPC ?
> >
> > Are there any tools availble for calculating timers, uarts etc. ?
> >
> > I know its much to ask, but if I ask very polite can I pursuade 
anyone to
> > take a brief look at my schematic to see if i've forgotton or was 
unaware
> of
> > any twinkles about the LPC connections !?
> 
> Welcome to the group, Lasse.
> 
> Philips recommends larger capacitors on the crystal (they have a 
table in
> the user manual): 68 pF for 10 MHz. I couldn't find them in 0805 so 
I use 56
> pF. They don't mention a resistor across the crystal.
> 
> I'd include the JTAG connector, it'll make debugging much easier. 
You'll
> need a Wiggler or equivalent, of course.
> 
> Fixed voltage regulators (1.8 V ones are difficult to find), will 
simplify
> the circuit a lot.
> 
> I'd use a MAX202 (100n capacitors) or a MAX3232 (3.3V) for the RS-
232. You
> won't need the pullups for the latter, of course.
> 
> The LCD should work off 3.3V (the Powertip ones I use do), although 
you
> might need a -ve supply to get the contrast control to work 
properly.
> 
> That's all I can think of.
> 
> Check your '2106 connections against my (much simpler) schematic, I 
know
> mine works. 8-)
> 
> Leon
> --
> Leon Heller, G1HSM
> Email: aqzf13@d...
> My low-cost Philips LPC210x ARM development system:
> http://www.geocities.com/leon_heller/lpc2104.html