CI‑V uses (one‑wire bidirectional data). The USB side (UART) is standard TTL (non‑inverted). So you need:
: A USB Type-B or Micro-USB jack connects to the host computer. USB-to-Serial Chip : The (or similar chips like the icom ci v usb interface schematic top
(typically 4.7kΩ to 10kΩ) is connected between the data line and +5V to maintain the bus in a high state when idle. Radio Side: A shielded cable terminating in a 3.5mm mono plug . The tip is the data line, and the sleeve is the ground. Simplified Wiring Diagram For those using a pre-made USB-to-TTL adapter (like those used for Arduino), the wiring is even simpler: Connect GND: Adapter Ground right arrow 3.5mm Plug Sleeve. Combine Data: Tie Adapter right arrow 3.5mm Plug Tip. Add Protection: CI‑V uses (one‑wire bidirectional data)
The most modern and simple approach uses a pre-built USB-to-UART module (such as the ) and a few discrete components. Core Components: USB-to-UART module, 1N4148 diode, and a Schematic Logic: The module’s cap T cap X cap R cap X USB-to-Serial Chip : The (or similar chips like
Below is a textual representation of the for a proven CI-V USB interface. Component values are typical for 9600–19200 baud operation (some radios support 38400 or 19200 baud; adjust accordingly).