My hardware project :: GCart 2011

[beamrider]

Really excited about this, could be the logical upgrade for a mega-cart.

[TLovskog]

Sorry, but I am closing down all my VIC 20 projects. I might take it up at one stage. It takes energy always have it the in back of my mind, but never time for it. After 9 years with a lot of prototypes, but few done to the end, that is it.

[joshuadenmark]

No rush, these projects takes time - will follow it when time comes.

[TLovskog]

Thanks!

I know, but 9 years

Anyway, I have had some really lazzy and relaxing days of and got some time last two days. So I actually couldn't really stay away so I just sent this for production. Yet another incarnation of my ideas.

[Noizer]

Nice to see that you haven't discarded all of your ideas! By the way, I would say materialize instead of reincarnation.

[beamrider]

Looks good, what has changed?

[TLovskog]

Mostly simplified the design, and also settled on an really old idea of simulating most of the RAM, ROM and IO subsystem in software. I tested that in 2012 with a dsPIC. but it wasn't really capable. I have then tried some different approaches with Cypress PSoC and FPGA.

I have since last year very good prices on STM32, so I have tested with STM32F429 and STM32F723.

I have also changed to another WiFi module from Dialog DA16600. That also includes BLE.

[TLovskog]

I also have this simple cartridge that is more for internal testing of a very small but dirt cheap programmable 5V tolerant circuit.

Still it has (intended to have) a simplified configurable RAM expansion on BLK1-3 and RAM1-3 with no banking. RAM on BLK 5 that can be write protected.

RAM at IO2/3.

There is also 1Mbit FLASH in 16 banks of 8k.

Although the BoM cost with components and PCB with hard gold is very low, I think the feature-set is a bit to limited compared to other cartridges out there, so this is more for internal use.

[TLovskog]

PCBs are on their way, and I have ordered all components for both boards.

I will start with the simple one since I need it for development of the code that goes into Dialog GreenPAK SLG46620 programmable logic. Array in quotes since it has VERY few LUT, but on the other hand costs nearly nothing, works with 5V and have just about enough for the glue logic I believe.

The BoM is quite favorable at under 5 USD including PCB, in volumes of 100.

[brain]

I'll put the UltiMEM schematics and such into github, as it sounds a lot like your current project (8MB FLASH, 1MB RAM, bankable blocks and rams and IO segments)

Jim

[TLovskog]

Great Jim!

[TLovskog]

At least I have something to do this weekend ... or next.

[TLovskog]

... and soldered. Everything except the digital FPGA. That will be connected to the emulator to start with.

[brain]

Here's the repo for UltiMEM:

https://github.com/go4retro/UltiMEM

And, the register description is here:

http://www.go4retro.com/products/ultimem/

Essentially, each of the various memory segments (RAM 1,2,3 | BLK1 | BLK2 | BLK3 | BLK5 | IO2 | IO3) can be set to read/write RAM, R/O RAM, ROM, or nothing, and each of the 7 blocks can be configured to live in any 8kB "page" in the various memory IC enabled for that segment. Thus, page values can be 0-1023 for ROM, and 0-127 for RAM.

Not sure if you can re-use any of the layout, but there's the scoop.

Jim

[TLovskog]

Thanks again Jim.