The PIC has a white arrow in the transistor and the clock is a little to the right.
Pull-down resistor Tact switches are in line with the lower back. PIC fast 200ns port in the meantime and have pressed any button to check each one to switch ON, OFF is a pseudo-noise in the oscillator. The PIC is more convenient and I was able to adjust the volume to a variable resistor connected to the base of the transistor because it connects directly drive the output speaker.
PIC16F84A Electric Piano: Dosya indirme LINK listesi (TXT formatında) link-5205.zip şifre-pass: 320volt.com