interesting project : ECART

For hardware talk only (please avoid ROM dumper stuff)
Shiru
Very interested
Posts: 786
Joined: Sat Apr 07, 2007 3:11 am
Location: Russia, Moscow
Contact:

Post by Shiru » Tue Jul 01, 2008 1:05 pm

TmEE co.(TM) wrote:I've got 2Mbytes worth of SRAMs, but total of 20...30 chips...
Are you really need 10-16MB SRAM cart?

TmEE co.(TM)
Very interested
Posts: 2373
Joined: Tue Dec 05, 2006 1:37 pm
Location: Estonia, Rapla City
Contact:

Post by TmEE co.(TM) » Tue Jul 01, 2008 3:25 pm

I really need at least 32Mbit cart... I will have to upgrade my flashcart to 64M soon.
Mida sa loed ? Nagunii aru ei saa ;)
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen

Shiru
Very interested
Posts: 786
Joined: Sat Apr 07, 2007 3:11 am
Location: Russia, Moscow
Contact:

Post by Shiru » Tue Jul 01, 2008 3:37 pm

TmEE co.(TM) wrote:I really need at least 32Mbit cart...
It's just eight 512K chips then, about $40.

HardWareMan
Very interested
Posts: 727
Joined: Sat Dec 15, 2007 7:49 am
Location: Kazakhstan, Pavlodar

Post by HardWareMan » Tue Jul 01, 2008 3:55 pm

TmEE co.(TM) wrote:...for a while I could locally buy 4Mbit SRAMs, but not anymore :(
I have this SRAMs. ;)
But, for testing purpose is enough small amount of SRAM with external storage support (i.e. SD/MMC/CF). And for gaming it's true - too small memory and we need NOR FLASH.
If we divide constructively device at 4 parts: FLASH cartrige for gaming, SRAM cartrige for programming and testing, modified Mega Key for use FLASH/SRAM cartrige with boot device and boot device to expansion slot with support storage SD/MMC or CF. So, MD will be able to program FLASH cartrige independ of PC and then FLSAH cartrige can be used alone without boot device for gaming. All you need is copy favorite ROMs on SD/MMC or CF storage.
OK, I will start work on this project as soon as I get enough free time for this. Of course, you will get all docs about this project. And if you will help me with OS, it would be just great!

patroclus
Newbie
Posts: 1
Joined: Tue Jul 01, 2008 4:09 pm
Contact:

Post by patroclus » Tue Jul 01, 2008 4:14 pm

Hello,

I made the ECART.
It does work, and it is already able to flash the cartridge from a CF card without a PC. Also, read/write to any place of memory map using a PC and parallel port, like transfer suite does.
Also I have a special hacked BIOS ROM to run from cartridge port, and be able to flash the ECART in the case something goes wrong.

Hopefully, I'll build the final PCB this week.
I'd like to add more support, but that depends on free time and other things.

Jorge Nuno
Very interested
Posts: 374
Joined: Mon Jun 11, 2007 3:09 am
Location: Azeitão, PT

Post by Jorge Nuno » Tue Jul 01, 2008 6:04 pm

TmEE co.(TM) wrote:I really need at least 32Mbit cart... I will have to upgrade my flashcart to 64M soon.

Use (S)DRAM instead... they're cheap, fast and have a bunch of megabytes inside them, but they require a multiplexed address bus, cell-refreshing and RAS/CAS signal generation.

I think they are worth against 32 SRAMs of 256KB

Those things could be implemented in a CPLD with like 40 IOs.
___

Also for HardwareMan, does your hard-drive have a standard file-system? Like FAT?

Can you run programs from it? they have to be copied into a ram buffer (because HDdrives are slow), right?

TmEE co.(TM)
Very interested
Posts: 2373
Joined: Tue Dec 05, 2006 1:37 pm
Location: Estonia, Rapla City
Contact:

Post by TmEE co.(TM) » Wed Jul 02, 2008 7:29 am

Jorge Nuno wrote:Use (S)DRAM instead... they're cheap, fast and have a bunch of megabytes inside them, but they require a multiplexed address bus, cell-refreshing and RAS/CAS signal generation.
The 3 things are a problem for me, at least for now, unless I get more educated about these things...
Mida sa loed ? Nagunii aru ei saa ;)
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen

Pascal
Very interested
Posts: 200
Joined: Wed Nov 29, 2006 11:29 am
Location: Belgium
Contact:

Post by Pascal » Wed Jul 02, 2008 7:47 am

patroclus wrote:Hello,

I made the ECART.
It does work, and it is already able to flash the cartridge from a CF card without a PC. Also, read/write to any place of memory map using a PC and parallel port, like transfer suite does.
Also I have a special hacked BIOS ROM to run from cartridge port, and be able to flash the ECART in the case something goes wrong.

Hopefully, I'll build the final PCB this week.
I'd like to add more support, but that depends on free time and other things.
hello patroclus,

welcome here , nice to see that you are still working on ecart :)

HardWareMan
Very interested
Posts: 727
Joined: Sat Dec 15, 2007 7:49 am
Location: Kazakhstan, Pavlodar

Post by HardWareMan » Wed Jul 02, 2008 11:04 am

Jorge Nuno wrote:Also for HardwareMan, does your hard-drive have a standard file-system? Like FAT?
Yes. My code supported FAT16 and FAT32 file systems. With long file names. ;)
Jorge Nuno wrote:Can you run programs from it? they have to be copied into a ram buffer (because HDdrives are slow), right?
Yeah, but not enough RAM for this. Basic internal RAM enough only for small tools.
So, here is draft of schematic diagramm for future device.
Image
For now, I will not explain how it will works. Later, when assemble device on PCB and do some debug stuff I will answer on all your questions.

HardWareMan
Very interested
Posts: 727
Joined: Sat Dec 15, 2007 7:49 am
Location: Kazakhstan, Pavlodar

Post by HardWareMan » Fri Jul 25, 2008 1:58 am

So, it is done! I can switch to software. If anyone want to help with it - welcome!
Image
Image
Image

TmEE co.(TM)
Very interested
Posts: 2373
Joined: Tue Dec 05, 2006 1:37 pm
Location: Estonia, Rapla City
Contact:

Post by TmEE co.(TM) » Fri Jul 25, 2008 2:03 am

really nice :)

Is the cartslot taken from a Famicom clone ?
Mida sa loed ? Nagunii aru ei saa ;)
http://www.tmeeco.eu
Files of all broken links and images of mine are found here : http://www.tmeeco.eu/FileDen

HardWareMan
Very interested
Posts: 727
Joined: Sat Dec 15, 2007 7:49 am
Location: Kazakhstan, Pavlodar

Post by HardWareMan » Fri Jul 25, 2008 2:14 am

TmEE co.(TM) wrote:really nice :)
Is the cartslot taken from a Famicom clone ?
How you guessed? :)

devzone
Interested
Posts: 18
Joined: Sun Jun 01, 2008 12:21 am
Contact:

Post by devzone » Fri Jul 25, 2008 4:44 am

very nice projects

I am curious about the read speed you have managed to get with the sd card as on a previous project (not megadrive related) of my own using a microcontroller driving the sd card I couldnt get a read speed faster than 0.5MByte/Sec :(

HardWareMan
Very interested
Posts: 727
Joined: Sat Dec 15, 2007 7:49 am
Location: Kazakhstan, Pavlodar

Post by HardWareMan » Fri Jul 25, 2008 4:51 am

devzone wrote:very nice projects
I am curious about the read speed you have managed to get with the sd card as on a previous project (not megadrive related) of my own using a microcontroller driving the sd card I couldnt get a read speed faster than 0.5MByte/Sec :(
And where you hurry? The speed of 0.5 Mbytes/sec is normal. The cartridge size is 4 MBytes, so it will be copied only 8 seconds. While 4 MBytes FLASH programming can take up to a few minutes...

devzone
Interested
Posts: 18
Joined: Sun Jun 01, 2008 12:21 am
Contact:

Post by devzone » Sat Jul 26, 2008 1:26 am

HardWareMan wrote:And where you hurry? The speed of 0.5 Mbytes/sec is normal. The cartridge size is 4 MBytes, so it will be copied only 8 seconds. While 4 MBytes FLASH programming can take up to a few minutes...
Thanks for the info, so my 0.5 wasnt as slow as I thought

Its a shame those flash devices are so slow to program, I may make a version of this dev board with added sram so that games/progs can be loaded quickly into the ram

Keep up the good work HardWareMan 8)

Post Reply