i assume that the MAX. input voltage is 5V and MAX input current is 50mA.Am i correct????
when a uC pin goes high what will be the voltage across it and also current????
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Now i am communicating with serial port RS-232 so i must create a driver or program that will get data from buffer and copy the data to a text file.so programming that in DOS or Windows is easy????
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and does any of the Atmel series of Microcontroller(8051) has an analog to digital converter(ADC) internal
If you want to use an A2D module, move on to AVRs or PICs. For the serial part, yes you will need a serial line driver (MAX232 is most common). Google it and you will see how.