4 I/O Interfaces
The I2C interface uses the SDA and SCL pins to transfer commands/data/status to and from the ECC204-TFLXAUTH device. The SWI transfers data using a single pin. Data flow is controlled by the host controller for both interfaces.
Interface Terminology
- Host:
- The host MCU generates the command and controls the data flow on the bus to one or more client devices.
- Client:
- The ECC204-TFLXAUTH device always operates as a client device on the bus and cannot take control of the bus.
- Device Address:
- 7-bit address used to address a client device. This is part of the first byte sent to a client device for each write or read transaction.
- Open-Drain:
- The ECC204-TFLXAUTH device has an open-drain output buffer where the bus is actively pulled low by the output buffer when data are read from the device but are passively pulled high by an external pull-up resistor.
Remember: The I2C
standard uses the terminology “Master” and
“Slave”. The equivalent Microchip terminology used
in this document is “Host” and “Client”,
respectively. This terminology was also adopted
for the SWI interface.