A USB→UART bridge is a small IC that converts USB data signals into standard UART (TX/RX) logic-level serial signals. It lets your CM5 (or any host with USB) communicate with UART-based devices—like GPS modules, debug consoles, or serial sensors—without using extra GPIO pins.
Key points:
- The bridge appears on the host as a virtual COM port (USB CDC)
- It provides TX, RX, RTS, CTS lines at 3.3 V (or 1.8 V) logic levels
- Common examples include FTDI’s FT232R, Silicon Labs CP2102, and WCH’s CH340
Typical integration:
- Connect the bridge’s USB D+ and D– pins to your CM5’s USB2.0 D+ / D– differential pair
- Route its VBUS sense and 5 V input to your power rail
- Wire the bridge’s TXD and RXD to the UART RX/TX pins on your CM5 header
- Optionally use RTS/CTS for hardware flow control
If you’d like to pick a specific bridge IC, let me know (for example, FT232R or CP2102) and I can find the exact part in the Flux library. Alternatively, here’s a generic search: