About 6 years ago we did a port of our ARM BASIC to the LPC812. While we built a handful of boards, it never became a product, as the LPC1114 came along and became our focus.
Though recently we needed a smarter interface for character LCD displays, and the LPC812 was a perfect fit.
The LPC812 has 16K of program memory, enough to contain an integer version of BASIC and 9K for user code. So below is the evolution of our LPC812 boards, starting with an LPC812 in a TSSOP package, deriving power from the 5V programming interface, at first using a 2V zener diode.
Next the LCD812 board connected to a 2 line LCD, but also setup for 4 line parts, using both 1x16 and 2x8 connections. We switched the power supply to an AP2210-3.3 low dropout regulator, as we use that in many of our boards these days.
And now an OSHpark built LPC812 breakout board. For the design we switched to an SO20 version of the LPC812 and 0805 caps to be user friendly for DIY soldering. The basic design is fully capable, but also very minimalist. 4 components and 2 connectors, schematic below.
The 3 design evolution below.
At present we don't plan to produce these boards as a product, but publish here the Open Hardware design.
If we get enough interest they may become products, drop us a line if your are interested.
And to build it yourself --
| Device | single unit price | Quantity |
|---|---|---|
| LPC812M101JD20 | $2.09 | 1 |
| AP2210N-3.3TRG1 | $0.43 | 1 |
| CAP CER 2.2UF 16V X5R 0805 | $0.17 | 2 |
| OSHpark PCB | $1.75 | 3 PCB min |
| PRPC006SBAN-M71RC (6 pin right angle header) | $0.19 | 1 |
So less than $5 to build it yourself, though you have to order multiple of 3 from OSHpark, share them with a friend.
For now here are the KiCAD files
And a zip file of the gerbers ready for OSHpark
And the BASIC firmware file