Is it possible to interface a type of pic microcontroller to another pic microcontroller, like you want to interface pic16f73 to another pic MCU? If yes, Explain How can be connected each other and what port or pin is used.
Yes, it is possible. I have connected a PIC 12F675 (which has an A/D converter) to a PIC 16F628 (that does not have an A/D converter, but it can control a LCD) in another board, via serial communication (USART hardware implemented in the 628 and software implemented in the 675). Some PICs have parallel ports (e.g. 16F877 that can be connected with other PICs). A very good example is the ICD2 clone that uses a 16F877 and a 18F4550 connected each other.
Do you have an idea how will I interface Pic16f84a (which has a lm35 temperature sensor and an external adc0804 ADC connected to it) to pic16f73.
heres a block diagram below.
Is it possible to interface a type of pic microcontroller to another pic microcontroller, like you want to interface pic16f73 to another pic MCU? If yes, Explain How can be connected each other and what port or pin is used.
Yes, I connected 2 pic micros using serial communication.In a project I had to implement 32 I/O ports.I used 16f877a to expand the port(maximum 31 I/Os).
and its working well.
I do not know why you need the 16F84 between the AD converter (unnecessary also) and the 16F73. You could simply connect the LM35 directly to 16F73 AD converter, you save two chips.
But nevertheless you could connect the two PICs via I2C protocol or even RS232. SPI is also an option. You should study serial communications protocol.
I used the 16f84a to perform a self-identification for recognizing the type of sensor that is attach to the mcu. The pic16f73 can't perform self-identification.