This project started as an experiment to identify the inner functions of a basic Digital Storage Oscilloscope (DSO). Unfortunately the project stopped but i managed to put together a tutorial in order for other engineers to follow up.
I used a STM32F4 discovery board with a 5 inch SSD1963 with parallel connection making use of DMA. That feature made it possible after struggling a bit with the code to have high refresh rates of the waveform.
There was no high-speed comparator on board the dev board in order to trigger the sampling of the analog signal. One way to overcome that problem was to simply sample without one! After processing the sampled data i had to cut a piece of the waveform at the very beginning in order to find the trigger level. That let me simulate the trigger function as if there was a high-speed comparator that did the job! Even though the lack of a comparator made the waveform look a bit unstable from time to time, it was ok for the purpose it was being built.
There is a step-by-step guide in the tutorial.
You will also find links for certain files such as:
- The original source code
- IDE download links
- uGFX graphics lib
- RTOS link
- Debugger link
- Makefile link