After implement the autofire using a DDS technique to make the autofire work (more on that later) I have the first full working version ready. Source is available at Github.
The autofire function modulates the TRIGGER A button at 8 Hz with duty cycle very close to 50%.
When Paddles are being serviced it is possible to observe3 the envelope of the autofire modulator.
Worth to mention that both captures have been done with Z button continously pressed to generate TRIGGER A + AUTOFIRE