Hi,
I`m trying to build a card to interface with the pc. I have found several tutorials explaining how to connect a PIC with the computer by different methods, that part is partially solved.
The problem: i have to control 3 groups of 20 pushbuttons and 1 group of 30 LEDS. I planned to interface with the pc using a PIC16F877A with 40 pis, so i have 33 IO pins. I dont know how to connect the pushbuttons and the leds...
-Is there any IC that allows me to expand the I/O ports?
-I thought that i can use a PIC to control each group (3 pics for the buttons, 1 pic for the leds, and 1 pic to interface with the pc). Can I connect 4 PICs to the one that drives the interface with the pc by I2C protocol? If so, could anyone post the scheme, please?
Thx in advance
I`m trying to build a card to interface with the pc. I have found several tutorials explaining how to connect a PIC with the computer by different methods, that part is partially solved.
The problem: i have to control 3 groups of 20 pushbuttons and 1 group of 30 LEDS. I planned to interface with the pc using a PIC16F877A with 40 pis, so i have 33 IO pins. I dont know how to connect the pushbuttons and the leds...
-Is there any IC that allows me to expand the I/O ports?
-I thought that i can use a PIC to control each group (3 pics for the buttons, 1 pic for the leds, and 1 pic to interface with the pc). Can I connect 4 PICs to the one that drives the interface with the pc by I2C protocol? If so, could anyone post the scheme, please?
Thx in advance