Icom Ci V Usb Interface Schematic Top Fixed -

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.

Many cheap interfaces omit the inversion on TxD and just swap RX/TX – this fails with Icom because the protocol expects the idle state inversion. icom ci v usb interface schematic top

Devices communicate by pulling the line LOW (0V). The simplest way to interface a standard USB-to-TTL

(Note: Some FTDI chips allow enabling internal pull-up on RxD, eliminating external 4.7k) icom ci v usb interface schematic top

(Computer Interface V) system is a bi-directional, single-wire serial bus used to control Icom amateur radio transceivers. While modern rigs like the Icom IC-7300

lines are bridged to create the single-wire CI-V bus. A diode is placed between the cap T cap X

CI-V requires an open-collector driver.