There was still a minor bug in the input section of the HiFiBerry DSP Light prototype. It was just a resistor that was soldered only on one side. After fixing this bug, the board it now working correctly. That means we have a DSP board that can be programmed from the Raspberry Pi and has analog inputs and outputs. I usually do the basic tests using a signal generator and the oscilloscope. However, a simple sine wave is a boring subject for a DSP. Simple biquad filters do not modify the waveform. But let’s see, what happens if we use the abs() function on a sine wave:
Oops, the signal is inverted. But this is not an issue, inverting a signal in the DSP is a trivial function.
That means we can now focus on the software development. The first step is the EEPROM functionality. With the onboard EEPROM the DSP works even without the Raspberry Pi (however without the option to control it over the network).
The next step will be a universal filter designer that can be used for crossovers, equalizing and even room equalization. The software will be open source. Are you interested to join the software development team? Contact us!