Sentinel65
This is the Sentinel65, a 6502 based bread board computer with 32KB of RAM, an R6551 serial UART running at 38400 baud, two VIAs, and 2MB of NOR flash memory via bit-banged SPI. It is very much a work in progress.
I started off following Ben Eater, of course, but began to deviate once I realized he only utilized 16KB of RAM. I didn't have a solid plan at first, so I just kept adding wires until I got the spaghetti you see here. I decided to forgo Ben's decoding scheme, opting for a 74LS688 + 74LS138 to allow for much tighter address decoding with almost no gaps. These will be eliminated in the future, however, in lieu of a series of AT22V10 PALs.
Included are a couple of pictures of my small bootloader program and BASIC running on my VT420.
In the future, I plan to add a DS1685 RTC, PS/2 keyboard support, a T6963-based bitmapped LCD, and extended terminal support, including color and Sixel/ReGIS graphics commands.
I am also teaching myself KiCad so I can migrate away from the breadboard and onto a PCB in the future.