Need more Arduino board? Do not spend more money for another one. Why not try to build your own DIY Arduino board? It is easy and simple.
DIY Arduino Step 1
Get an Atmega328–PU or Atmega328P-PU (with bootloader inside).
atmega328p
A brief introduction on the Atmega328 chip:
- 8-bit MCU
- 32kB Flash Memory
- 1kB EEPROM
- 2kB SRAM
- 23 general purpose IO lines
- 6-channel 10 bit ADC
- SPI and I2C capabilities
Make Your Arduino Step 2
Connect the circuit as below:
TAKE NOTE
In this post, I will talk about uploading sketches using FTDI programming port. In the next post, I will talk more about uploading sketches and burning bootloader using the ICSP programming port. Get one FTDI programmer here.
Build Your Arduino Step 3
Now I will address one of the issues of making your own Arduino. On the Uno boards, there’s an IC which is responsible as a USB to serial converter and it makes it possible to program the Arduino and also communicate with it from the computer.
The problem here is the IC is an SMD (Surface Mounted Device). The R3 uses an ATmega 16U2 while the older revisions uses the 8U2. So, we need an FTDI programmer for the purpose of uploading the code/sketch into the chip.
When you first plug in your FTDI programmer into your laptop, you have to install the driver file. Get the driver file here.
Once installed, just connect the FTDI programmer to the FTDI programming port of DIY Arduino accordingly.
Finally just click on upload to upload the code into the chip!
If you don’t have the extra 16 MHz crystal and 18-22 picofarad capacitors used in the above examples, you can configure the ATmega328 to use its internal 8 MHz RC oscillator as a clock source instead. You don’t really need the 10K pullup resistor on the reset pin either, so we remove it to get a truly minimal configuration.
For more detail: Construire Votre Propre Carte Arduino
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