now really i don't understand how to write a command which can keep on monitoring whether data have arrived on POrt 1 or not.Like for bit i can use:- JNB P1.0,$ but how to monitor entire port. So firstly tell me how to do that ?
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Read the port and save the value exactly as you are doing. Then compare it to the previous read. If they are different then the port has changed. Save the new result as the previous result.
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now here something i need to know, if i divide a binary 8 bits number with 10 as done above will the data i will get will be in the MSB = A , and LSB = remainder value in B.)
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Yes this is correct.
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can the above be done using only one port but not changing any hardware or doing multiplexing..
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No.
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