Intel 4040

Intel 4040

An Intel D4040 Microprocessor
Produced	From 1974 to 1981
Common manufacturer(s)	Intel
Max. CPU clock rate	500 kHz to 740 kHz
Min. feature size	10μm
Instruction set	4-bit BCD oriented
Predecessor	Intel 4004 Intel 8008
Successor	Intel 8080
Package(s)	24 pin DIP

The Intel 4040 microprocessor was the successor to the Intel 4004. It was introduced in 1974. The 4040 employed a 10 μm silicon gate enhancement load PMOS technology, was made up of 3,000 transistors and could execute approximately 60,000 instructions per second.

New features

i4040 microarchitecture.

• Interrupt
• Single Step

Extensions

Intel 4040 registers

12 11 10 09 08 07 06 05 04 03 02 01 00 (bit position) Accumulator     A Accumulator Condition codes   C Carry flag Index registers   R0 R1 Index bank 0   R2 R3     R4 R5     R6 R7     R8 R9     R10 R11     R12 R13     R14 R15     R0 R1 Index bank 1   R2 R3     R4 R5     R6 R7   Program counter PC Program Counter Push-down address call stack PC1 Call level 1 PC2 Call level 2 PC3 Call level 3 PC4 Call level 4 PC5 Call level 5 PC6 Call level 6 PC7 Call level 7

• Instruction Set expanded to 60 instructions
• Program memory expanded to 8 KB (13-bit address space)
• Registers expanded to 24
• Subroutine stack expanded to 7 levels deep

Data Bus:4-bit
Address Bus:12-bit
Voltage:+15V

Designers

Federico Faggin proposed the project, formulated the architecture and led the design. The detailed design was done by Tom Innes (Tinnes of Bristol).

New support chips

• 4201 – Clock Generator 500 to 740 kHz using 4 to 5.185 MHz crystals
• 4308 – 1 KB ROM
• 4207 – General Purpose byte Output port
• 4209 – General Purpose byte Input port
• 4211 – General Purpose byte I/O port
• 4289 – Standard Memory Interface (replaces 4008/4009)
• 4702 – 256 byte UVEPROM
• 4316 – 2 KB ROM
• 4101 – 256 4-bit word RAM

Production

Philippines