Frog Bog Prototype Release

[thewaxcylinder]

Today I am releasing a prototype of Frog Bog for Intellivision. This was dumped from an EPROM cartridge yesterday. I was told that I should also release it here, so I will. Provided in the zip file is the BIN and CFG files needed for emulation and/or flash carts. The file is also available on archive.org with the provided link

https://archive.org/details/frog-bog-proto

please enjoy!

FrogBogProto.zip

[decle]

Hi @thewaxcylinder, thanks for sharing this.

 

It seems as though the Maxflash Studio used to dump the game has generated an image of the Intellivision's full 64K memory map for some reason, rather than just the contents of the game ROM.  The addresses between $0000-$4FFF and $6000-$FFFF in the binary file are all padding.  Unfortunately, once this padding is removed and the 4K game that is left is compared with the production version, they look to be identical.

 

Sorry to disappoint you.

 

 

Cheers

 

decle

 

 

Oh, I should add that the reason the Maxflash image crashes in emulators like JzIntv, which obviously the production version doesn't do, is entirely because of this padding!  It is declared as ROM with a fixed value of $FFFF (well that or $7FFF where the Maxflash has had a bit of a hiccup) and interferes with the other devices in the memory map.  Remove it and everything works perfectly.

 

I'd also advise against trying to run the Maxflash image on a Flash cart.  If the Flash cart is not constructed defensively, this image could cause it to try to compete with other IC's in the Intellivision to return data from shared addresses (e.g. the GRAM, GROM, STIC, etc).  This is a bad idea, and might (if you're really unlucky) cause damage to either the Inty or Flash cart.

Edited July 15, 2023 by decle
Added reason for crashes

[+sfish]

I have a MaxFlash and have dumped older and newer Intellivision carts. The older, original cart dumps can be played successfully but the newer ones generally can't - even those not assumed to be copy protected. Without the advantage of a working .bin file to compare it to (like with Frog Bog), I would assume there is little chance I could review and manually edit sections of a newer cart's .bin to get it to work. 

 

Is there any hope of a solution here or should I just assume the MaxFlash simply won't be able to produce functional dumps for modern INTV carts?

[mr_me]

2 hours ago, sfish said:

I have a MaxFlash and have dumped older and newer Intellivision carts. The older, original cart dumps can be played successfully but the newer ones generally can't - even those not assumed to be copy protected. Without the advantage of a working .bin file to compare it to (like with Frog Bog), I would assume there is little chance I could review and manually edit sections of a newer cart's .bin to get it to work. 

 

Is there any hope of a solution here or should I just assume the MaxFlash simply won't be able to produce functional dumps for modern INTV carts?

If the cartridge emulates an Intellivision rom chip with a microcontroller, the cartridge may not show the game code unless it sees Intellivision signals. Otherwise, if the Maxflash isn't compatible with Intellivision bankswitching it won't read those cartridges properly. 

Edited June 5 by mr_me

[+sfish]

Makes sense. I'll do a little more exploration and see if I can't get it to work. Thanks!