# What protocol does the Vertex VX-2200/2100 use for programming?

I have seen a number of programming cable schematics on the internet, but I couldn't understand very much how they worked. From what I picked from all schematics, it appears the protocol uses the CL_DATA pin for both RX and TX, and the CL_SW pin to signal stuff.

However, I couldn't really understand the protocol that the radio uses. Can someone please explain? What are both the radio and the computer interfaces sending and expecting in each pin?

• Just FYI: don't use the programming tag for "radio programming" — it's for computer software. An unfortunate naming problem, I know. I'm thinking about how to improve it. – Kevin Reid AG6YO Oct 9 '16 at 13:49
• @KevinReidAG6YO OK. How about splitting the tags into radio-programming and computer-programming? – Ronan Paixão Oct 9 '16 at 14:10
• Yeah, that's a possibility. I just posted a meta question about this and some related lacks-of-tags, if you'd like to see more of the problem. – Kevin Reid AG6YO Oct 9 '16 at 14:15
• If I understand correctly: Yaesu ./ Vertex professional have kind of UART interface (similar to RS-232, different voltage), and agree, TX&RX are connected – Jacek Cz Oct 12 '16 at 13:38
• Software protocol is (as far I know) hidden (not known / proprietary) – Jacek Cz Oct 12 '16 at 13:41