Make Your Own Oscilloscope(Mini DSO) With STC MCU Easily Using Atmega

Material List:

• MCU: STC8A8K64S4A12 x 1 Get it from AliExpress
• Display: SSD1306 OLED(5V with 7-Pin SPI Interface) x 1 Get it from AliExpress | Get it from Amazon

• Resistor:
  • 1W 10k x 1 Get it from AliExpress
  • 1/4W 2k x 2 Get it from AliExpress | Get it from Amazon
  • 1/4W 10k x 1
• Capacitor:
  • 47uF x 1 Get it from AliExpress | Get it from Amazon
  • 0.01uF x 1 Get it from AliExpress
• EC11 Encoder x 1 Get it from AliExpress | Get it from Amazon
• Toggle Switch x 1 Get it from AliExpress
• 2-Pin Terminal x 1 Get it from AliExpress
• IC Socket 40-Pin x 1 Get it from AliExpress
• Row Pin Female: Get it from AliExpress
  • 7-Pin x 1
  • 2-Pin x 1
• 3.7V Li-ion Battery x 1 Get it from AliExpress
• 5V Booster Module x 1 Get it from AliExpress
• USB-TTL Downloader x 1 Get it from AliExpress
• Circuit Board x 1 Get it from AliExpress

Step 3: Scheme and Circuit!

The circuit is very simple.

The final circuit is a little different from the video.

I add two capacitors as MCU power filter. Add a resistor as voltage dividing for voltage sampling of battery.

Move the switch to Battery+ and power module to avoid the drain current during stand by.

Step 4: Download the Code!

Use a USB to TTL downloader to download the code to MCU

Connect TXD, RXD and GND to the Mini DSO.

Download STC-ISP software here: http://www.stcmicro.com/rjxz.html

If the interface of STC-ISP is Chinese, you could click upper left icon to change language to English.

The detail configuration of STC-ISP please refer my video above.

The code was written in C. Use Keil software to edit and compile.

Step 5: Success!

Here you could observe waveform easily with this Mini DSO.

It also could be used to measure voltage.

Add a probe to the terminal, it could be easily working in hand.

Step 6: Issue

Since this Mini DSO could not measure negative voltage, the waveform will stop at 0V.

Step 7: Related Topic

I also made a Function Generator with STC MCU. The waveform shown on the Mini DSO is just generated by my DIY Function Generator. If you are interested in it, you could watch my video now. I will create the instruction later.

Step 8: Update in the Future

The new functions for the Mini DSO is being developed. They are Normal Sweep and Single Sweep. With these functions you could observe the waveform mutation. In the picture, it is the waveform mutation of the switching power supply during power on. We catch the wave rising just same as the oscilloscope DS1052E.

Read more: Make Your Own Oscilloscope(Mini DSO) With STC MCU Easily