I also saw the program “How to interface computer’s Serial Port (RS232) with 8051 microcontroller (AT89C51) ” in this website, and IIIiIIIIIIIII
I use the Keil C emulator to run the C progran on 8051 board which is connecting to PC through UC232A ( a device of rs232 (9 pin device) to USB (insert to PC)).
When I type the Keyboard on PC, There is no any ‘char’ shown on the Hyperterminal.
But I change the program which is download from http://www.keil.com/forum/933 , I can see the result on Hyperterminal.
By the way , I am not fully understand some sentance in C program such as P1=value & P2=P1-32 for what function and I could not see P1 & P2 port connection in the circuit.
Thanks for help!