Intel 4040 (i4040) is an enhanced version of
Intel 4004 microprocessor. The 4040 runs
at the same at the frequency as the 4004 and has the same effective
speed of instruction execution - 92,000 instructions per second for
single-word instructions. The CPU includes the following enhancements:
- Maximum program memory size was increased from 4 KB to 8 KB.
- Stack size of the 4040 CPU was increased to 7 levels.
- Extra bank of eight 4-bit registers was added to the CPU.
- The microprocessor included interrupt support.
- 14 instructions were added to i4040 instruction set.
- Full list of differences between Intel 4040 and
4004 microprocessors.
Intel 4040 was used in Intellec 4/40 microcomputer development system
and in in embedded applications.
There are no known second-source manufacturers of Intel 4040
microprocessor.
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