The CI-V protocol is a . Unlike standard RS-232 serial communication which uses separate Transmit (TX) and Receive (RX) lines, CI-V combines them into one "DATA" line. Idle State: The line is held high (+5V TTL). Collision Detection: If the line is low, the bus is "busy".
The simplest way to interface a standard USB-to-TTL module (which has separate TX and RX pins) with the single-wire CI-V bus is to bridge the signals. icom ci v usb interface schematic top
Multiple Icom devices can be connected in parallel; each is identified by a unique hex address. Core Schematic: USB-to-TTL (CI-V) The CI-V protocol is a