Good day Freaks!
I have a question that I would to get an opinion. As some may know, my big project I have been working on is an arcade machine. I have the majority of the systems prototyped with breadboards (audio, video, and controller input) and working great. I have slowly been working on getting things together for the main driver board.
However, recently this week I have been prototyping the audio system. Now this works great in it's current state (I have only been at it for about a week, so it's still pretty early in breadboard stage).
For the final design, I would like to integrate an SPI Flash memory chip that will go on the cartridge for the games.
Now the problem I seem to have encountered in my searching is that SPI Flash chips all seem to be 3.3v logic (the ones I found on DigiKey and Mouser). I would like to integrate at least 2MB (16MBit) but preferably something more like 4MB or even 8MB.
Currently, my video driver is based on 5 volt logic and is using an ATmega1284. I have this board already designed and routed. It is currently the only major system that is actually routed.
I would like all my main chips to be running the same logic level as the game cartridge CPU will communicate with the audio and video systems via SPI.
TLDR:
Most modern SPI Flash chips I've found are 3.3v volt logic and my current design is 5 volt. I see a few options here:
- Scrap my current video driver design which uses 5 volt logic and develop everything (audio and video) with ARM technology
- Use resistor dividers on the logic/supply pins for SPI Flash chips?
I have yet to get a stable image using an ARM processor (was testing on a D21 and it had way too much jitter) and that is why my current design uses an AVR8, as I was able to get perfect cycle timing using assembly.
Either way, I would still like to get VGA video working with an ARM but at this point I am just looking at a way to learn more options in this.
I really hope this isn't just a completely stupid question. Thanks for your help!