i have released my everdrive MD flashcart for SEGA

KRIKzz · Post by **KRIKzz** » Sat Feb 27, 2010 4:25 am

revision 2.0 available now!

device description:

Flash cart for SEGA megadrive/genesis

+SEGA megadrive/genesis games supported.

+SEGA maser system games supported.

+32kb FRAM for game saves keep.

+save ram data can be stored or loaded from SD card

+saves available for megadrive/genesis and master system games

+SD/MMC cards support.

+FAT16 support. 2GB max partition size

+cart can change console region, for disable regional securuty.

+connection to PC and any additional software is not required

+button for pause in SMS games

+module system

more info you can see on my website. so say hi (:

TmEE co.(TM) · Post by **TmEE co.(TM)** » Sat Feb 27, 2010 8:56 am

This is looking very very lovcely, I hope you'll be able to sell lot of those

Chilly Willy · Post by **Chilly Willy** » Sat Feb 27, 2010 7:36 pm

Looks good! I'll have to get one.

Stef · Post by **Stef** » Sat Feb 27, 2010 8:48 pm

oh sweet !

eteream · Post by **eteream** » Sat Feb 27, 2010 11:03 pm

lovely!
I need one of those. You have an email.

What about save state feature? Just kidding! But... is it possible?

KRIKzz · Post by **KRIKzz** » Sat Feb 27, 2010 11:52 pm

eteream wrote:lovely!
I need one of those. You have an email.

What about save state feature? Just kidding! But... is it possible?

save state like on emulator? i think it is impossible, but... snes have device for save state. in any case i have not idea how is it work (:

KRIKzz · Post by **KRIKzz** » Sun Feb 28, 2010 12:18 am

i publish everdrive OS src, modules, hardware spec and videofiles

Stef wrote:oh sweet !

BTW you GenesisDev04 help me to build software for this cart (:

Mask of Destiny · Post by **Mask of Destiny** » Sun Feb 28, 2010 8:58 am

Question: What kind of storage does this card have for the ROMs that are loaded off the SD card? Is it RAM or flash?

The reason I ask is that I don't personally have much interest in a flash-cart, but a reasonably priced RAM cart is very interesting to me, especially one with an SD interface.

How much storage is available on the cart to hold the ROM? 4MB?

KRIKzz · Post by **KRIKzz** » Sun Feb 28, 2010 2:24 pm

Mask of Destiny wrote:Question: What kind of storage does this card have for the ROMs that are loaded off the SD card? Is it RAM or flash?

The reason I ask is that I don't personally have much interest in a flash-cart, but a reasonably priced RAM cart is very interesting to me, especially one with an SD interface.

How much storage is available on the cart to hold the ROM? 4MB?

ROM memory based on m29w640, it is flash, 8mb, but only half of this chip used for ROM

Stef · Post by **Stef** » Sun Feb 28, 2010 6:52 pm

KRIKzz wrote: BTW you GenesisDev04 help me to build software for this cart (:

Glad it helped you

eteream · Post by **eteream** » Mon Mar 01, 2010 1:53 am

KRIKzz, is possible to replace the OS (boot, menu, etc...) with custom one?

(to enjoy personal graphics, for example)

HardWareMan · Post by **HardWareMan** » Mon Mar 01, 2010 3:46 am

eteream wrote:KRIKzz, is possible to replace the OS (boot, menu, etc...) with custom one?

(to enjoy personal graphics, for example)

I think it's not a problem. All you need is to know hardware memory and register map.

KRIKzz · Post by **KRIKzz** » Mon Mar 01, 2010 3:57 am

eteream wrote:KRIKzz, is possible to replace the OS (boot, menu, etc...) with custom one?

(to enjoy personal graphics, for example)

yes, but be careful. cart will be damaged if you replace main and reserve copy of OS by some inoperative. for restore, in this case, must be used external device, for reprogram bios. you can test costum OS before original OS will be replaced, just install this as module and run

Graz · Post by **Graz** » Tue Mar 02, 2010 1:56 am

KRIKzz wrote:ROM memory based on m29w640, it is flash, 8mb, but only half of this chip used for ROM

That is a 3.3V supply part with an absolute max supply voltage of 4V. I assume you've used a 3.3V regulator for supply, but I don't see any level shifters in your pictures and the IO isn't 5V tolerant. How does it handle being stuffed on the 5V 68K bus?

KRIKzz · Post by **KRIKzz** » Tue Mar 02, 2010 2:20 am

Graz wrote:
KRIKzz wrote:ROM memory based on m29w640, it is flash, 8mb, but only half of this chip used for ROM
That is a 3.3V supply part with an absolute max supply voltage of 4V. I assume you've used a 3.3V regulator for supply, but I don't see any level shifters in your pictures and the IO isn't 5V tolerant. How does it handle being stuffed on the 5V 68K bus?

VCC Max = 4.0v
VIO Max = VCC +0.6 = 4.6
and maximum voltage may overshoot to VCC +2V during transition and for less than 20ns during transitions.
so all is ok