This little board demonstrates the capabilities of the MMA2260 +/- 1.5g X-Axis Micromachined Accelerometer. As you tip it back and forth, LEDs light up to show the magnitude and direction of the G force.
The MMA2260 is the fat SOIC 16 in the upper left, isolated so it could be cut off of the board and used as a breakout, keeping only a pin header and the recommended decoupling and output RC filter.
The microcontroller is a PIC16F628, which is entirely unsuited to this application, having no ADC. I failed to notice that, being quick to note “AN0″ on PORTA and slow to note that it was for a comparator, not an ADC. However, there is a builtin programmable voltage reference which was sufficiently accurate for lighting up 8 LEDs. I’m trying to get away from PICs, as AVRs have spoiled me with their GCC support, many registers and sane memory organization. Even on this project, which is only about 30 lines of C, most of the work was fighting SDCC bugs (failure to banksel, in this case). I’ve discovered a perverse pleasure in soldering down ICs to counteract my packrat nature. It did force me to put an ICSP header on, however.
MMA2260 Accelerometer Demo - [Link]
The world of electronics is moving further and further away from Through-Hole components and towards SMT (Surface Mount Technology) every day. Sometimes this doesn’t always go well for the enthusiasts building at home, so we have to adapt.
DIY SOIC to DIP Chip Adaptors – [Link]
Pyra wanted to program an ATtiny13 microcontrollers in a SOIC package so he made an adapter out of a PCI socket. This programming clip, after a little modification fits perfectly on the chip. On the image above are not shown the soldered wires that will help to program it.
Build your own SOIC progamming clip - [Link]
This is small versatile USB board developed by Brian Schmalz. He used PIC-USB capable microcontroller for easy USB interfacing and this way got simple parallel port replacement.
There is not much about circuit itself as there is only PIC microcontroller, USB connection and I/O pins. Such simple design allows making smal PCB that may fit anywhere starting from integrating in to test-boards and ending as stand alone applications. Author have compiled a nice list of various board versions that include different PIC microcontrollers, different PCB types that can fit in various applications like for plugging to breadboard, or very small SOIC board for tiny projects. Author also provides a list of various firmware versions along with bootloaders. To make things more easier there are few demo applications available for testing or modifying to your own needs. [via]
Simple PIC USB I/O board - [Link]
Here’s an outstanding surface mount soldering guide from curious inventor -
Surface Mount components, as the name suggests, attach to the surface of boards, not through holes like older components. SMDs (“Surface Mount Devices”) are lighter, cheaper, smaller and can be placed closer together. These factors, among others, mean that the days are numbered for through-hole components with widely spaced leads.
This set of guides will demonstrate (relatively) inexpensive tools and methods for soldering and desoldering SMDs. The first page, Surface Mount Soldering 101, contains a 9 min. video overview. The pages that follow contain more pictures and go into more detail. They also cover some topics not in the video, like hand soldering a QFN chip and using solder paste with a toaster oven. [via]
Surface mount soldering guide - [Link]