Protocols#
The wires between chips. UART, SPI, I2C, 1-Wire, CAN, USB, RS-232, RS-485, JTAG, SWD, and I2S; the protocols an operator sniffs, replays, and impersonates on a target’s bench.
Asynchronous serial. TX, RX, ground; the console hidden behind every embedded device.
Master-slave clocked serial. The bus to every flash chip; pull firmware in a few hundred milliseconds.
Two-wire multidrop. SDA and SCL; the sensor and EEPROM bus on every board.
Single-wire serial. Power and data on one line; iButtons, temp sensors, and badge dongles.
Automotive bus. Differential pair, message-based; the protocol on every modern car’s diagnostic port.
Universal Serial Bus. Differential pair plus power; the most-attacked, most-impersonated edge of any host.
Asynchronous serial with bipolar voltages. The legacy industrial UART; still on most factory floors.
Differential multidrop serial. Long runs, noisy environments; the BACnet, Modbus, and DMX backbone.
Boundary-scan and debug. Four or five wires; the back door for firmware dumps and chip control.
Serial Wire Debug. The two-wire JTAG replacement on ARM Cortex-M parts.
Inter-IC Sound. The digital audio bus between a codec and an MPU.