Rolling your own ROM files?

[+Larry]

...or you can buy a Maxflash USB programmer with software suite from Atarimax and avoid all the hardware "fun." You also end up with a great programming tool for Atarimax flash carts and MyIDE's and probably some other flash carts that support the device.

 

http://www.atarimax.com/flashcart/documentation/

 

-Larry

[russg]

There's a couple of inordinately simple ways of doing it if you get lucky. Easiest IMHO is just get OMNIMON OS in some flavor. With the cartridge inserted you just press reset while holding down the OPTION + SELECT keys and that gets you to the monitor. From the monitor, just type B with a DOS disk in your drive and you will be at the DOS menu. A simple binary save of the cartridge address will save the image with the aforementioned 6 header bytes. Kind of neat to have a game cart inserted with the DOS menu staring at you.

 

There's some odd stuff Atari did to save a buck. Lots of their 8k carts took up the full 16k but only had one ROM inserted. All you do to copy the binary is pull the existing EPROM<or ROM>, move it to the other socket, and insert a BASIC EPROM<or ROM, whichever the case may be> into the original occupied socket and boot the cart. It will come up 8k short of free RAM for BASIC *BUT* the 8k address space will be the original cart ROM.

 

There's some variation on the second method. If you modify the cart lines, you can actually have a cart that only goes from $8000-$9FFF. You can boot to built in BASIC on an XL this way and still have the ROM of interest in the memory map.

All this time, I didn't realize the 'B' boot command of Omnimon. That makes the cart dump easier, just have to strip the first six bytes to make a ROM. And you don't have to write to sectors, then read from sectors.

[russg]

I modified the 800XL MMU so that the internal BASIC is replaced by the cartridge you have plugged into the system. If you boot normally with no cartridge or boot with OPTION pressed, the cart is disabled. In the first case, you have 40K of memory (boot with no cart and press OPTION for 48K). In the second case, the cart is disabled but it still 'locks out' either 8K or 16K, depending on the size of the cart. You want to do this so that the OS does not put your screen in the cartridge space.

 

If you plug in a cart and power on without pressing OPTION, the system comes up normally with the cart functional.

 

So, the procedure is: plug in a cart: power on with OPTION pressed: load your dump code: clear bit 1 in $D301 with your dump code (this enables the cart): dump 8K or 16K.

 

As with anything 'different', some programs are bound to want to help and disable BASIC for you, which disables the cart, instead. You can still dump the cart OK, but you can't run it.

 

Here are two files, the CUPL code and the JEDEC output. I used an ATMEL ATF16V8B chip so the JEDEC file is only good for that. You may need to change the Target chip and re-compile if you are using another device.

 

All I did in the code is disable the BASIC output and add !BE to S4 and S5.

 

Try it!

 

Bob

 

 

800XLCOPY.zip

Thanks. I believe .jed and .pld are code for eprom burner. I'm not familiar with them. Nice solution.

[+bob1200xl]

PLD is CUPL source code. You compile it to JED files that you use in your GAL programmer. You end up with a new MMU chip.

 

Bob

[+bob1200xl]

I can make chips for anybody who wants one...

 

Bob