if you are looking for a free alternative to commercial C cross compilers like Keil for the MC51 platform then SDCC is the answer. Here is a link to SDCC's knowledge base.you can download SDCC from the sourceforge.net repository.
Harish Srinivas
“Autodidact with an insatiable thirst for learning something new everyday. Wearer of many hats. DevOp Engineer/Release Engineer, Security Engineer, Linux fanatic, Amateur photographer, Maker & Novice App developer.”
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