Hi
I am new at C programming so bare with me. Can you please give me the code for writing a program using a 4x3 keypad with a 74c922 encoder chip in C? I know that when your DA pin is set high, it tells the program that data is available, but how do you wright the code to go fetch the data? Can you help me, I'm really struggling. When the DA pin goes high it must trigger an external interrupt(INT0) and then detect which key was pressed according the encoder chip. This data must then be sent to the LCD. Each character on the LCD must correspond to the pressed keybutton. This must happen each time a keypress takes place.
I'm using Keil uVision2, for programming. I'm using it to wright the program and then generating the hex files to put on a 27C256 eprom connected to a Intel 8051 Microcontroller. Which is connected to a 4x3 keypad and LCD, with the 74C922 encoder connected to the keypad and the encoder connected to the data bus of the microcontroller. I'm also using a 3-to-8 line decoder chip(74HC138) connected to all the IC's and to the data bus of the microcontroller. Can you help?
Any help would be greatly appreciated!
Regards and Thanx,
Ruben
I am new at C programming so bare with me. Can you please give me the code for writing a program using a 4x3 keypad with a 74c922 encoder chip in C? I know that when your DA pin is set high, it tells the program that data is available, but how do you wright the code to go fetch the data? Can you help me, I'm really struggling. When the DA pin goes high it must trigger an external interrupt(INT0) and then detect which key was pressed according the encoder chip. This data must then be sent to the LCD. Each character on the LCD must correspond to the pressed keybutton. This must happen each time a keypress takes place.
I'm using Keil uVision2, for programming. I'm using it to wright the program and then generating the hex files to put on a 27C256 eprom connected to a Intel 8051 Microcontroller. Which is connected to a 4x3 keypad and LCD, with the 74C922 encoder connected to the keypad and the encoder connected to the data bus of the microcontroller. I'm also using a 3-to-8 line decoder chip(74HC138) connected to all the IC's and to the data bus of the microcontroller. Can you help?
Any help would be greatly appreciated!
Regards and Thanx,
Ruben
