i am going to do a 8052 based project in which we must be interface two s-series 8052 with each other but we have no idea about it. can anybody help me to suggest me how to interface two 8052 together.
thus our problem is that we are unable to join all that one in one microcontroller due to lack of I/O port and space. sure you can if you want to stay with a '51 there are 8-porters giving you 64 I/Os, not to mention MMIO or port expanders. Or go for an ARM where the sky is the limit
Erik
1) SPI consumes one extra pin (slave select) for each extra peripherial device you connects. May be EEPROM, RFID reader, bus expansion ... You can even connect external UART, or Ethernet over SPI.
2) I2C consumes zero extra pins for connecting more hardware. So if EEPROM uses I2C then you can get a bus expansion with zero extra processor pins.
3) It is trivial to connect latched shift registers, consuming 3 bits (latch,shift,data out) to drive any number of output signals. Or you could instead use shift registers for reading lots of input signals. And they are cheap.
4) 40-pin DIL isn't the only alternative out there.
5) 8051 isn't the only alternative out there.
There are many, many options available when designing a system. A large part of the design is to consider what processor to use and what peripherial hardware. Many times, you same money by getting a bigger processor since you pay very little for the extra peripherial support that gets included with the bigger chips. That is one of the reasons why the ARM chips have taken lots of market ground.