In my recent experience with the ATtiny2313, I had problems with the serial communication at 8Mhz. Which in turn my research led me to learning about tuning the internal oscillator. The ATtiny is a small microcontroller by Atmel, the same company that makes the ATmega328p in the Arduino UNO. It doesn’t have all the features but it is cheap and great for embedding in projects. Here is a link to more info on them: http://www.atmel.com/products/microcontrollers/avr/tinyavr.aspx . The great part is that there is a add-on for the Arduino IDE called Arduino-Tiny. This way you can use the same code with the ATtiny’s.
After some trial and error and some help from the forms, I was able to figure out how to tune the ATtying2313 and get reliable serial communications. As a result I decided to design a kit that makes it much easier to tune.
The TinyISP-Tuner connects to your computer via a FTDI cable and has an ATmega328p as the controller. The ATmega328p is running the TinyISP sketch with tuning and KnockBang. KnockBang allows you to pass serial debug info via SPI over the FTDI cable to your computer. Very convenient. When tuning is enabled there is a 16ms pulse sent out to the ATtiny you are programming. Plus you can program the ATtiny once it is tuned with your sketch. All with this one kit.
Supports ATtiny84/44/24, ATtiny85/45/25, and ATtiny2313/4313.
• 1x PCB
• 1x 6pin Right Angle header for FTDI programming
• 1x Atmega328p DIP (Pre-programmed with TinyISP configured for tuning)
• 1x 16Mhz Resonator
• 2x 0.1uF Capacitor
• 1x 10K Resistor
• 1x 330Ohm Resistor
• 1x Red LED
• 1x 20pin socket
• 1x 14pin socket
• 1x 8pin socket
• 1x 28pin socket
Check out the guide: http://friedcircuits.us/docs/tinyisp-tuner/
If you want to buy one: https://www.tindie.com/products/FriedCircuits/tinyisp-tuner/