#3954 Breadboard a 4-Bit Computer
#3954 Breadboard a 4-Bit Computer #3954 I want to breadboard a 4-bit computer. 16 commands and 4-bit address space. Describe what I will need. This is a classic project, often referred to as the SAP-1 (Simple As Possible) architecture. The constraints you listed (16 commands, 4-bit address space) fit perfectly into an 8-bit instruction word structure: the upper 4 bits define the Opcode (16 commands), and the lower 4 bits define the Operand (the memory address). Even though the instruction word is 8 bits wide, the computational core (ALU) and registers can be kept to 4 bits to satisfy your "4-bit computer" goal. Here is the breakdown of the hardware, logic, and architecture you will need. 1. The Core Architecture (The "Mental" Breadboard) You are building a bus-based architecture. All components connect to a central data highway (The Bus). The Bus: 8-bits wide (to carry instruction + address in one go). ALU (Arithmetic Logic Unit): 4-bit (performs math). RAM: ...