Intel 4004 - Technical Specifications

Technical Specifications

• Maximum clock speed was 740 kHz
• Instruction cycle time: 10.8 µs (8 clock cycles / instruction cycle)
• Instruction execution time 1 or 2 instruction cycles (10.8 or 21.6 µs), 46300 to 92600 instructions per second
• Separate program and data storage. Contrary to Harvard architecture designs, however, which use separate buses, the 4004, with its need to keep pin count down, used a single multiplexed 4-bit bus for transferring:
  • 12-bit addresses
  • 8-bit instructions
  • 4-bit data words
• Instruction set contained 46 instructions (of which 41 were 8 bits wide and 5 were 16 bits wide)
• Register set contained 16 registers of 4 bits each
• Internal subroutine stack 3 levels deep.