Two bank eight image ROM cartridge
This cartridge is a development from three devices/cartridges I've made in the past. The first time I made a switchable ROM was way back in the early 1990's, then, about 5 years ago I made a switchable battery backed RAM cartridge giving 2 banks of 16 images each, the BBSRAMextreme. More recently I made a very slimmed down 32K cartridge that is small to suit my Electron Ultra and it is this I want to make some changes to.
The alterations will include increasing the ROM size to 128K, giving each bank four switchable images and adding a small piano style switch to make the selection as easy as possible. I kept the board size the same and added a space to note the image names readable from the front.
more to follow..