Sound generation method

I have two Pocket Pianos (one silver with hold, one green without). I have always been curious if the audio generation is digital, an analog circuit, or a hybrid. How are the different tones generated?

Thanks for getting two Pocket Pianos!

The synthesis is digital.

They are incredibly immediate and a lot of fun. Sometimes I wish there was the ability to use a mode with a slow attack, but it is what it is. I have other synths (including an Organelle M) for that functionality anyway.