CAUTION: Please note that I do not take any responsibility or liability for any damage or mulfunction caused through this page. To modify or bend any circuits is all at your own risk.
a) do not experiment with the pins on the other side of YM2154 chip because it will do critical damage to RX21.
b) bent point of YM2154, there is a risk that user memory area may be lost lost because of error and hang-up when used with the other bent point.
c) may damage the speaker because of high volume of self-oscillation by NJM4556D(IC116 pin 1 to IC118 pin 3).