Because CI-V is a "half-duplex" single-wire system (the radio and the computer take turns talking on the same wire), you cannot simply tie the TX and RX pins directly together without risk of contention. However, with FTDI chips, there is a trick:
Situate the steering diode and the 4.7kΩ pull-up resistor as close to the 3.5mm jack footprint as possible to minimize stray capacitance.
pull-up resistor (R3) between Pin 8 (VCC) and Pin 6 (Output) of . icom ci v usb interface schematic top
If you choose to etch your own PCB or build this on a prototyping perboard, . Keep all copper traces on the USB side at least 2mm away from all copper traces on the Radio side. Do not bridge the grounds under the optocouplers; keeping them separate is the entire purpose of an isolated schematic. Software Configuration
Solder the of the 1N4148 diode directly to the TXD pad on your USB module. Solder the other side (anode) of the diode directly to the RXD pad. Step 3: Connect the CI-V Cable Take your 3.5mm mono cable or connector: Because CI-V is a "half-duplex" single-wire system (the
Thus, on both the receive and transmit paths.
Combine the separate TX and RX lines into a single, bi-directional 3.5mm mono line without causing data collisions. The Core Schematic Components If you choose to etch your own PCB
What are you building this interface for?
The radio transmits status data or frequency updates back to the PC over the same Tip wire.
Easy Setup
5 Star Support