The StripDuino Mk1.5 had a number of flaws. Mainly in that there was no mechanical design! How was I going to mount it onto anything? In working on rearranging the board to include mounting holes and another design that included the L293D for driving some motors I had some ideas for more improvements. Instead of making a complete board for each project, why not create the StripDuino board plus a shield design? Then I can make endless shields without having to re-make the processing part each time. Where have I seen this idea before?
So, this version includes the following improvements:
- Female header sockets for the StripDuino Shield (see future post)
- Mounting holes
- +3.3V Regulated Supply
- DC Power Jack connection
There are some compromises to this new design:
- The ATMega328’s Analogue Reference (AREF) pin is not available. If this is important to you, you’ll need to modify the design.
- The green LED connected to D13 cannot be seen once a shield is mounted. This LED is traditionally for early “Hello World” applications, so should not be a big deal.
- FTDI connection
- 7 – 9V DC in using the DC power jack on the top left hand corner above the FTDI connection.
- Regulated 5V DC in using the connection in the top right corner of the board.
I tend to buy Atmel ATmega328P-PU microcontrollers from eBay with the Uno bootloader
already loaded. All I have to do is upload my sketches using a FTDI USB-TTL 6 PIN adapter to connect the PC to to the 6 pin header on the board. These can be bought from eBay for under a fiver and only one is needed to program as many boards as you like. I’ve found that the order of the pins may vary with these FTDI boards, particularly the Rx & Tx lines can be swapped around. Just experiment until it works.
The FTDI connection order on this verboard version are as follows, from top to bottom:
- Not connected
- +5V in
- DTR (reset)
Bill of Materials
- 16MHz Crystal Oscillator
- LM7805 Voltage Regulator
- LD1117V33 Voltage Regulator
- 1N40001 Diode
- 100uF Electrolytic Capacitor – 4 off
- 100nf Ceramic Capacitor
- 22pF Ceramic Capactor – 2 off
- 3mm Red LED
- 3mm Green LED
- 10K Resistor
- 560R Resistor – 2 off
- 28 Pin DIP Socket
- 2.54mm (0.1″) header sockets
- 2.54mm (0.1″) header pins
- DC Power Jack
- Miniature Momentary Action Push to Make Push button Switch
Figure 2 shows the front of the veroboard:
Figure 3 shows the rear of the veroboard:
Figure 4 shows the pinout details for the 2 headers: