I am able to download from the VX-170 but not upload.

I take it that the same "clone" mode is used for download and upload.

I note that the data for Rx and Tx go through the same pin on the 4 pin yaesu connector.

I assume that the Rx and Tx data alternate on the same line because it is shared.

Question: When uploading to the radio , does the software need to Tx and Rx to/from the PC to the radio or does it just Tx from PC to radio ? ie is there handshaking involved or just a steady transmit stream from the PC to the radio?

tnx

Mike VE7SML