Educational Computer Cart crashes and some games do not work

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Educational Computer Cart crashes and some games do not work
by on (#107822)
Some time ago, I found a cart on the bazar, which reveald itself not being a poorly made clone cart. It has some neat apps on it like a beatmania clone with songs and solitaire and such. If I put it in my famiclone, the cart starts up, but after some seconds, it crashes. After resetting like 100 times, I am able to select some apps.
Is there any way to make the cart work properly? It seems that on the cart there are components missing, but they seem to be missing on purpose. Here are some pictures:
Re: Educational Computer Cart crashes and some games do not
by on (#107823)
Some more pics
Re: Educational Computer Cart crashes and some games do not
by on (#107857)
Very interesting cart :? Looks like xNROM with 16*32kB(?) PRG ROM
Could you please post pictures of scrambled graphics? No need high-res, 800*600 is fine, but no flash, please.
It could be a)degraded CHR RAM chip b)damaged PCB vias c)menu code check presence of keyboard

Is anyone knows about dump? If not, requesting dump.

added

Where is the WRAM? :?
Re: Educational Computer Cart crashes and some games do not
by on (#107946)
Sry for taking that long to answer.
I think this cart uses PRG and VRAM, there is no WRAM on the carts board.
These are games giving scrambled graphics everytime I start these or they wont even start.
I would really like to dump this cart, but I dont have proper hardware to do so.
Any advice?
Re: Educational Computer Cart crashes and some games do not
by on (#107995)
I would try to resolder vias. But it's VERY delicate task. After that dump asap. If you don't have eqipment for dump, better to send cart to someone, who could do that.

There is G-Basic on the list and usually it's just patched Family Basic, so it needs WRAM
Re: Educational Computer Cart crashes and some games do not
by on (#108376)
Any updates?
Re: Educational Computer Cart crashes and some games do not
by on (#108380)
The glop top on the PCB could certainly contain PGR-RAM. The best thing to do would be to send the cart to someone with a CopyNES that knows how to use it to prove the cart and dump it. Is this cart rare or fairly common?
Re: Educational Computer Cart crashes and some games do not
by on (#108388)
I'd say more unususal, since it was sold with keyboard style clone.
Re: Educational Computer Cart crashes and some games do not
by on (#108391)
I recently got some supplies from china(took about 3 weeks to arrive).
I am about to build my own copyNES and a famicom adapter for my original NES.
I think it will take some time, but as soon as I am finished, I can post the dump of the cart.
Re: Educational Computer Cart crashes and some games do not
by on (#108505)
I've got the same cartridge. Its banking system uses non-mirrored registers at $4800-$4803.

I asked CaH4e3 and apparently uses mapper INES 178.
Re: Educational Computer Cart crashes and some games do not
by on (#108547)
socram8888, could you please check which version of basic included in your cart and size of WRAM. PM with link on dump would be very appretiated.
Re: Educational Computer Cart crashes and some games do not
by on (#108566)
I think it fakes 65000 bytes or something, but it goes nuts when you input more than ~300 bytes, as it has no WRAM and stores the program in the main RAM.

I haven't done a full dump, altough I dumped the keyboard routine manually by peeking on BASIC. I can upload a patch for official BASIC 2.1 if you want.
Re: Educational Computer Cart crashes and some games do not
by on (#108568)
@socram8888, if your cart is working, could you please check what my cart lacks or what the problem could be?
i would like to be able to use all the apps on this cartridge.
Re: Educational Computer Cart crashes and some games do not
by on (#108581)
It's not physically the same cartridge, but it has the same software. Mine has both chips on the same board side, and it has a 32KB CRAM chip with upper addresses tied to VCC.
Re: Educational Computer Cart crashes and some games do not
by on (#108614)
socram8888 wrote:
I think it fakes 65000 bytes or something, but it goes nuts when you input more than ~300 bytes, as it has no WRAM and stores the program in the main RAM.

I haven't done a full dump, altough I dumped the keyboard routine manually by peeking on BASIC. I can upload a patch for official BASIC 2.1 if you want.

It would be nice to see patch. Thanks in advance.
Re: Educational Computer Cart crashes and some games do not
by on (#108635)
http://www.mediafire.com/?fc84177a8ykymnb
Re: Educational Computer Cart crashes and some games do not
by on (#108738)
Thanks for uploading patch.