Gain understanding of the inner workings of an Arithmetic Logic Unit (ALU), one of the building blocks of processors. Control the one-byte storage of the accumulator using the load and clear buttons. Get feeling with the adder-concept, all carries are visualized using small LEDs. While the carry-in can be set using the slide switch, the carry-out LED indicates a byte overflow.

Subtraction can be done using the method of complements, as explained in the Quick Start documentation. Jumpers can be set to externalize control of the accumulator, i.e. tie load and clear to the action- or clock-signal. Use the DIP-switch to turn off the intermediate-carry or separate the adder into two 4-bit adders.

The 8-bit Workbench™ can be attached at the top. With this you have an annotated 8-bits binary LED display. It talks hexadecimal and octal. A clicky Digitast action-button provides a properly debounced signal for use with microprocessors. With it you can further learn about logic and see how number systems work. For binary data-input, a Binary Keyboard can be attached at the bottom. This provides a joyfull toggle experience for 8-bit data input. Instead, use the Hex Keyboard to input a hexadecimal value directly.

Extend and combine this Byte Adder Subtractor with our other kits to learn and do (vintage) computer experiments. Visit our store to get more information on those products. A discount is applied when you order a combination of these kits that connect together.

See the documentation for details. Questions? Just ask!

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