here's the STM32F469 development board I am thinking of using. It presents equivalent to an early iphone, has the same look and feel with 680x480 resolution. Only problem with the board is the one I have has developed a crack in the cable or maybe it is just loose. The screen is sort of flickering that goes away when I press on the right side where the cable is captured under the display. The display itself is no more than 1/32nd thick with a backlight about 3/32nds. The display was rubber-glued down and I guess it dried out over the year or so since I bought it.
The board itself has all the features we need including 5 leds, SDCard, audio, mics, adc, dac, etc, etc. Don't think I'll be using much of that, though. The encoder will be mounted to the right with three buttons under it. I'll use the display for the 10 buttons and wire that into the accessory jack. If I can figure out how to enumerate two devices (encoder and keyboard) then I can send the recorded CW and voice buttons directly instead of the extra wire into the accessory jack. That is much cleaner, I'll admit, but haven't figured it out. I am getting pretty good with all this USB stuff though.
One thing nice about this board is that it presents to a connected PC as a USB drive so for firmware updates, you just take the executable and copy it over. Don't have to mess with DFU, etc.
Here's the board with an early keypad overlay from another project. I am using this one for testing and will hope to design some cooler looking buttons consistent with the IC-7610 display.
Overall, fun project now that I have it all working.
Jerry
by the way, the second USB is for the integrated debugging. The white cable goes to either a PC running RS-BA1 software or the supported Icom radio.