The Intel MCS-51 (commonly termed 8051) is an internally Harvard architecture, complex instruction set computer (CISC) instruction set, single chip microcontroller (µC) series developed by Intel in 1980 for use in embedded systems.
[env:stable]
platform = intel_mcs51
board = ...
...
[env:development]
platform = https://github.com/platformio/platform-intel_mcs51.git
board = ...
...
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