Hi all,
I’m just getting started with ARMs…and I figure the best way is to build my own prototype board.
Does anyone have a barebones LPC2103 schematic they could share? I’d like to understand what’s required in the way of pull-ups, decoupling etc. before spending time and money on boards 
TIA,
-marc
I have a basic LPC2106 design that should be OK for the LPC2103 (it might need one or two changes):
http://www.geocities.com/leon_heller/lpc2104.html
You could check it against one of the Olimex LPC2103 board schematics to see if anything needs to be modified.
Leon
Maybe this one would help:
http://www.olimex.com/dev/lpc-h2103.html
In general you need power supply (with LPC2103 3.3V an 1.8V), some XTAL, one RC for reset and pullup at P0.14.
If you download flash via bootloader, just put jumper on P0.14 to pull it down during reset.
For using JTAG you’ll need some extra pull-ups/-downs. Check schematic from link above.
Thanks guys, that helps a lot.
-marc
Also check out the LPC2103 errata sheet: you need 1.95V not 1.8V.
Luckily I’d stumbled across your website the other day and saw that! That’s a pretty big error 
-marc
Actually the core does need 1.8V but it is 2V tolerant. There is a voltage drop that is variable between the pin and the core. I figure at 20MHz or lower, the 1.8V will suffice and work well. Even at 60MHz if the supply can supply enough amperage at 1.8V it should work. The errara says it actually goes below 1.8V at high power so we should start with 1.95V.
This is important since I dont know of any dual power supplies supplying 1.95 and 3.3V. I have some chips from TI providing 1.8V and 3.3V fixed which makes things easy enough. The next step is more like 2.5V and 3.3V. I imagine to get the 1.95V you’d have to use dual power supplies with the 1.95 being variable. PITA.