- dropped support for OLD TXB with MCP4551 (see ERRATA)
- added support for NEW TXB with AD5245
- added timeout for busy-waiting peripheral (UART, I2C, SPI) interaction; on timeout, the MB indicates an error state through LEDs
- updated AD5245 interface/driver to support two devices (distinguished through A0 bit)
- tweaked TX/RX switch sequencing