[chirp_devel] Questions about "Special Channels" especially WRT Yaesu FT1D/FT2D

[NNN Wx]

When I look at a chirp “Memories” window, there’s a button called “Special Channels” which AFAICT does exactly nothing for my FT2D. I can find no description in the Wiki of the “Special Channels”. I AM ONLY IMAGINING WHAT THESE COULD BE, but I have some thoughts.

- The FT2D has several sets of preset channels: international VHF Marine, worldwide broadcasts, NOAA weather channels. That’d be perfect for “Special Channels”, although they are supposed to be read-only [but they have locations in the FT2D memory image, so it’s not unlikely that chirp can read AND write these locations.] Of course, it’d be illegal and impolite to try to TRANSMIT to those frequencies, so I may want to find a “do not transmit” flag to go with them.

- The FT2D has a subset of the memory locations that can only hold “skip” frequencies: whenever a scan is enabled, if the frequency matches a skip frequency that frequency is not used. These locations ARE programmable and contiguous with regular memory; at present, I’ve implemented them as memory locations that are forced to have a “Skip” flag.

So, please, dear developer experts: 
	Where are the “Special Channels” documented? 
	How does chirp access and define the “Special Channels”? 
	What data structures and methods are needed to implement them? 
	Would either (or both?) of the two above sets of locations be appropriate for inclusion as “Special Channels”? 
	Did I miss “Special Channels" in the underlying FT1D driver that I’m using to implement FT2D?

These questions are prompted by a preliminary bug report; one user seems to have used the FT2D to enter a preset channel into a memory bank, after which chirp refuses to edit the whole bank! I’ll be submitting a bug report Real Soon Now since it’s clearly a feature that the radio can handle. I’d hope to have a fix researched and suggested shortly thereafter.

Declan
WD5EQY