This project multiplies two 3-bit numbers (with a 4th bit being added as a leading zero) to an 8-bit output value. This then gets shown by the integrated 7-segment display in hex. It switches between the most and least significant nibble (4 bits). If it shows the least significant one, the dot is activated as well.
Project 23 on TT02: 4-bit Multiplier
GitHub repo containing the GDS of the 4-bit Multiplier
- Tiny Tapeout 2 Demo Board
no additional hardware needed!
Select the project by setting the DIP switches to 000 010 111.
The project specifies a 2.5kHz clock, however others have shown to work as well. This clock is expected on pin in0, and could be suppplied externally. The board also features a built in oscillator with a clock divider. The divisor is chosen by the input byte and locked in by plugging in the provided bridge into the SLOWCLK pins at the top left of the board. After that, the inputs can be used in a regular fashion.
I have tested the project running with the clock divisor initated at 0000 0000 for 2kHz and 0000 0001 (in0 high) for 1.2kHz and both worked perfectly fine.
It is advised to reset any device before using it. To do this, switch in1 to high and back to low (the reset is active high).
Now the inputs in2 to in4 can be used to put in the first number, and the inputs in5 to in7 the second number. For an example, let's multiply the numbers 0100 and 0101 which should yield 20.
The output can be read as described in the introduction: 1 and 4. are in hex. First convert to binary and then join them to a full byte, e.g. 0001 0100, which is 20 in decimal. It works!