MICROFORUM

here is one VHDL clock done https://www.fpga4student.com/2016/11/ve ... -fpga.html

that interests me: How can a calculator circuit that can perform 4 basic operations be turned into a programmable calculator? Using a microcomputer? It makes no sense with a microcomputer if the microcomputer itself replaces the calculator circuit. I can't imagine this expansion without a microcompu...

The diagram is correct. The negative pole is really up and the positive pole is really down. You can calculate the values ​​of the components according to the input voltage (transformer) and the output voltage you want.

I made this power supply