Example – basic oscilloscope

This example gives a basic overview of how one could use an FPGA in an embedded project. It uses the FPGA to sample an input and measure a voltage or similar, the way an oscilloscope would. The resulting ADC data is then sent over a serial link to a C++/Qt-based application, which displays the data.

The hardware

For the project, we will use a Fleasystems FleaFPGA Ohm board (http://fleasystems.com/fleaFPGA_Ohm.html). This is a small, sub-$50, sub-€40 FPGA development board in a Raspberry Pi Zero form factor:

It has the following specifications:

• Lattice ECP5 FPGA with 24K LUT elements and 112KB Block RAM.
• 256-Mbit SDRAM, 16 bits wide and 167 MHz clock.
• 8-Mbit SPI Flash ROM for...