Uart
Advantages : single wire, easy interface to PCs,MCU UARTSs etc. range of standard physical interfaces (TTL, RS232, RS422, RS485) covers a big range of distance/speed capabilites with off-the-shelf hardware.
Disadvantages : Needs reasonable clock accuracy both ends. Max data rate in practice about 1mbit/sec (typically limited by UART capabilities).
SPI
Advantages: Potentially very fast (10-20mbits/sec), very simple interface, very easy to implement in hard logic,FPGA or software.
Self-clocking so can wake an MCU on reception and have the data byte available once woken.
Flexible data word sizes
Disadvantages :
Multiple devices need multiple select lines.
I2C
Advantages :
Only 2 wires to support multiple devices. Multimaster capability
Timing constraints of protocol reduce likelihood of false data (e.g. eeprom corruption) in noisy or powerup/down situations.
Disadvantages :
More complex protocol than SPI, harder to level-shift or optoisolate due to bidirectional lines.
Speed up to 400kbit/sec (1mbit for a few devices), but in practice can be limited to lower rates by capacitance if tracks are long.
Advantages : single wire, easy interface to PCs,MCU UARTSs etc. range of standard physical interfaces (TTL, RS232, RS422, RS485) covers a big range of distance/speed capabilites with off-the-shelf hardware.
Disadvantages : Needs reasonable clock accuracy both ends. Max data rate in practice about 1mbit/sec (typically limited by UART capabilities).
SPI
Advantages: Potentially very fast (10-20mbits/sec), very simple interface, very easy to implement in hard logic,FPGA or software.
Self-clocking so can wake an MCU on reception and have the data byte available once woken.
Flexible data word sizes
Disadvantages :
Multiple devices need multiple select lines.
I2C
Advantages :
Only 2 wires to support multiple devices. Multimaster capability
Timing constraints of protocol reduce likelihood of false data (e.g. eeprom corruption) in noisy or powerup/down situations.
Disadvantages :
More complex protocol than SPI, harder to level-shift or optoisolate due to bidirectional lines.
Speed up to 400kbit/sec (1mbit for a few devices), but in practice can be limited to lower rates by capacitance if tracks are long.
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