1.2.2 Crypto Devices
Four Microchip CryptoAuthentication™ devices are included on the CryptoAuth Pro Trust Platform. Each device has a unique I2C address and can coexist on the same I2C bus. This particular bus is shared only with the I2C connections of the mikroBUS™ MB1 connector. The MB1 mikroBUS connector allows other cryptographic devices to be connected to the board.
On the backside of the board is an optional SOIC footprint that can be used with other
I2C CryptoAuthentication or CryptoAutomotive™
devices. Devices mounted to this footprint will be connected to the same I2C
interface as the crypto devices mounted on the board.
Important: Ensure that any device mounted to the optional footprint has a
unique I2C address, distinct from those of the devices directly mounted
on the board.
| Device | Default 7-bit I2C Address | I2C R/W Address Byte Values | |
|---|---|---|---|
| Write | Read | ||
| ATECC608C-TCSM | 0x60 | 0xC0 | 0xC1 |
| ATECC608C-TNGTLS | 0x35 | 0x6A | 0x6B |
| ATECC608C-TFLXTLS | 0x36 | 0x6C | 0x6D |
| ECC608-TMNGTLS | 0x38 | 0x70 | 0x71 |
Microcontroller Interface
The CryptoAuthentication devices are connected to the microcontroller only through the I2C bus. There are no other signals that can be connected. The devices are powered with 3.3V. Each of the I2C signals has a 10k pull-up resistor.
- Signal Connections: PA23(SCL), PA22(SDA)
- PA22(SDA) - Sercom #3. Pin Mux Configuration: IOSET1-PAD0
- PA23(SCL) - Sercom #3. Pin Mux Configuration: IOSET1-PAD1
- Special Considerations: Set Dip Switch S500 to select the on-board connection and optionally disable the mikroBUS connections. Note that both switches can be enabled, provided that no device has a duplicate I2C address. The kit protocol software will currently only detect up to eight devices on the I2C bus.