[SOLVED] Interfacing 89C52 with 23s17

[Rajarajan2809]

Is it possible to interface 89C52 with 23s17 (port Expander), If it is possible means whether interfacing through TXD and RXD is good or using General purpose Port pins for SPI

 

[FvM]

You can't use UART for SPI. A software SPI, using any 4 available port pins will work. Using an I2C port expander could reduce the pin count to 2, but needs slightly complexer software.

 

[Rajarajan2809]

Thanks...can u explain about SPI using 4 port pins

 

[FvM]

Pins are SCK, SDO(MOSI), SDI(MISO) and chip select (SS). All signals are generated by software (so called bit-banging). There are plenty of examples on the internet.