The 3870 (MK3870) 8-bit microcontroller is a single chip implementation of
Fairchild F8 (Mostek 3850).
The microcontroller includes up to 4 KB mask-programmable ROM,
64 bytes scratchpad RAM and up to 64 bytes executable RAM. The MCU also
integrates 32-bit I/O and programmable timer. In addition to generic MK3870/xxx-xx
markings the 3870 chips also have device order number in the form "MK#####x-xx".
Mostek also produced MK38P70 - development version of the 3870 MCU
that supported external EPROM chip.
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