A board that can be used for testing purposes
The schematic diagram (XC4870.Srmsgl) was made using xcircuit.
This is an experiment to see if the bootloader can be reprogrammed, and to check the clock speed. It can!
The sketch for this is mhz85.ino.
Operating it:
- In the Arduino IDE, set the clock speed that you want to use.
- upload the sketch onto an ATTiny85
- transfer the chip onto the board, and power up. The red LED should be on, and the green one off.
- Click the button and start a stopwatch simultaneously. The red LED goes off, and the green one goes on. The chip does a lengthy computation to test the clock speed.
- Wait until the red LED comes on again. Stop the stopwatch and record the time.
Results:
| Clock | Time |
|---|---|
| 1 MHz | 146s |
| 8 MHz | 18s |
- "Clock" is the clock speed set when uploading the sketch
- "Time" is the time taken to run the calculation (lower is faster).
Note that 146/18 = 8.1, which confirms that the 8MHz version is running 8X faster than the 1MHz version.
Performs a slow alernation between green and red LED. Speeds up whilst the button is held down.
The sketch for this is green_red.ino.