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This is a 4X4 binary shift multiplier.
The multiplicand input is represented by the four logic sources on the right. Simply set these sources for the desired multiplicand. The MSB is the leftmost input, the LSB the rightmost.
The multiplier must be shifted into the 4 bit shift register located on the bottom right.
Use the logic source at the middle left to select bits to be input serially from left to right into the register, and clock each selection into the register using the bottom leftmost logic source. This is achieved by setting the logic source HIGH and then LOW between each multiplier input. Remember that the MSB is the leftmost displayed bit, the LSB the rightmost.
Now make sure the multiplier input is set low, and again use the bottom left logic source to clock the multiplier through the register. It requires four clocks to shift the multiplier through the register. After four clocks, the product will be displayed.
To reset for now set all inputs low and clock all bits out of the shift register.
The algorithm of multiplication is quite straightforward. The LSB of the multiplier is multiplied with the multiplicand using the four AND gates and shifted towards the right. We then multiply the next bit and add to the shifted result using the 4 bit adder at the top right. Again multiply add then shift, multiply add then shift, and in this way all partial then shifted products are added to achieve the final product.
Remember, once you have your chosen multiplier, it requires four clocks for the desired product
Enjoy.
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