Building

keil µVision project (community version):
1. new project --> target: AT89C51 / generic 8051
2. add the .c file to the source group
3. build (F7) → simulate in the peripherals window (timer/port views)

if you're feeling rebellious (expect syntax fixes for sbit/interrupt):
sdcc -mmcs51 first.c

_{maintained by @devoltamp · one lab session at a time.}