Nice Circuits - Electronics, 3d printing and robots

Cheap ($1) chinese USB to RS232 TTL modules from eBay. Works fine and is cheap enough to be thrown anywhere. Windows drivers download: http://www.arduined.eu/ch340g-converter-windows-7-driver-download/ CH340G datasheet (third-party translation): http://cdn2.boxtec.ch/pub/diverse/ch340g-datasheet.pdf Schematic (reverse engineered): Source version (KiCad): https://github.com/NiceCircuits/modules_from_china/tree/master/CH340G_D-SUN-V3.0 PCB with marked components: Other photos:

I’d like to share a little tool that I made while debugging communication between Arduino and ESP8266. It’s a serial terminal, but not the classic one - it connects to two serial ports at the same time. The task is simple. I want to the spy serial communication at both lines at the same time. The hardware is simple too - I connected both serial lines to Rx pins of two serial-USB converters.

Today I’m going to present some of more advanced capabilities of ADC built in ATSAM3X8E - the heart of Arduino Due. I like the Arduino platform. It makes using complex microcontrollers much simpler and faster. Lets take for example the analog-to-digital converter. To configure it even on Atmega328 (Arduino Uno/Duemilanove) you must understand and set correct values in 4 registers. And it can be much more in complex device, like 14 in ATSAM3X8E (Arduino Due)!

There is a printer that I built some time ago. It’s modified Prusa i3 with bigger print area. It’s 300x300x200mm instead of 200x200x200mm. It may sound like nothing difficult, but it wasn’t so simple ;) Enlarging frame was quite easy (even that I mistaken in one place and had to add some plastic parts afterwards). The biggest problem was the heated bed. 1,5 times longer and wider it' has more than 2 times bigger area.

I use 0603 resistors and capacitors as standard size. In smaller PCB’s with higher component density I use 0402. They are both quite easy to hand solder if you have some practice and some flux. But what about smaller components? I always like to test my abilities, so one day I thrown some 0201 resistor footprints in the corner of one of my boards and bought 50 of them to try if I can solder them.

Sometimes you need to drill a hole, nice hole, precisely in some place. It can be difficult, especially in hard materials like steel. Best way in such case is to mark center of a hole with a punch to guide drill at this point. Until recently I known only one tool for such job – classic center punch bashed with the hammer. But I discovered better tool! Automatic center punch.