Intel MCS-51 (8051)

Configuration:platform = intel_mcs51

The Intel MCS-51 (commonly termed 8051) is an internally Harvard architecture, complex instruction set computer (CISC) instruction set, single chip microcontroller (uC) series developed by Intel in 1980 for use in embedded systems.

For more detailed information please visit vendor site.

Stable and upstream versions

You can switch between stable releases of Intel MCS-51 (8051) development platform and the latest upstream version using platform option in “platformio.ini” (Project Configuration File) as described below.


; Latest stable version
platform = intel_mcs51
board = ...

; Custom stable version
platform = intel_mcs51@x.y.z
board = ...


platform =
board = ...


Name Description
tool-stcgal Open Source STC MCU ISP flash tool
toolchain-sdcc Small Device C compiler suite


Linux Users:

Windows Users:

Please check that you have a correctly installed USB driver from board manufacturer




Name Debug MCU Frequency Flash RAM
Generic N79E8432 No N79E8432 22MHz 4KB 512B
Generic N79E844 No N79E844 22MHz 8KB 512B
Generic N79E845 No N79E845 22MHz 16KB 512B
Generic N79E854 No N79E854 22MHz 8KB 512B
Generic N79E855 No N79E855 22MHz 16KB 512B


Name Debug MCU Frequency Flash RAM
Generic STC15F204EA No STC15F204EA 11MHz 4KB 256B
Generic STC15F2K60S2 No STC15F2K60S2 6MHz 60KB 2KB
Generic STC15W204S No STC15W204S 11MHz 4KB 256B
Generic STC15W404AS No STC15W404AS 11MHz 4KB 512B
Generic STC15W408AS No STC15W408AS 11MHz 8KB 512B
Generic STC89C52RC No STC89C52RC 11MHz 8KB 512B