Kroko

Maybe this is what you need ? tia_map.txt

Yes, I know. Maybe I find a way to make it cheaper. On the other hand there are no components on the board I could transfer to the programmer. But maybe I can make the board smaller, single sided and find a company who is assembling them for less than I had thought For some reason, I love the connector But on the other hand I got a mail from Digi-Key that the connectors I ordered from them will become obsolete

I wonder how Parker did it with a 22pin chip. http://www.atariage.com/cart_page.html?SoftwareLabelID=1955 I almost agree with supercat, apart from the 9 banking outputs. I think 3 are sufficient. The 3 outputs control A10 to A12 on the Rom chip. In addition PB could skip the 2 lines for the timing circuitry, because it is contained in the custom chip.

Sure, Nathan designed it http://www.atariage.com/features/contests/KrokodileCart/

As I see it it is just storing a few bank numbers in a few registers. Just like F8,F6,F4 and any other banking scheme. It is confusing for most people if you tell them that E0 was a bs mode which requires a RAM chip, because it is Superchip, FA, E7,AR etc.. which actually do require RAM. F8,F6,F4,3F,F0 and E0 don't.

Lets say it like this: If anybody woud ask me about 2600 bankswitching modes and ask if F8,F6,F4 or E0 required RAM, I would still say: no it doesn't. Would you say yes ? I don't doubt that a register is a storage element, but I don't call a chip RAM just because it can somehow be used to store information. To close this discussion lets summarize it like this: cats are more tolerant with regard to what is called a RAM chip than krokodiles Maybe I should have said: Standard Programmable Logic chip. I didn't have in mind a certain chip type. The point was, that no RAM chip is required. Its not important if you do it with a XC9536XL or a 26V12. I am sure nobody would put a RAM chip on board (at least not if you take the krokodile definition of RAM chip )

True, but I would have used two caps I didn't want to say it is needed. I just wanted to say that it is better.

I also think that it is best to place a 100 nF capacitor between each VCC pin and ground. I would put one close to the inverters VCC and one close to the EPROMs VCC

Yea, pricing for memory chips is somewhat strange. At least it does not only depend on speed or memory size. A few month ago, the 128K chip was cheaper than the 64K chip at my supplier. A week later, the 256K chip was cheapest and now the 64K chip is cheapest

Yes, that really looks like overkill at first sight. But it is still cheaper that an EPROM and I need a chip type that can easily be reprogrammed. Do you think there is a better chip type I could use ? What you see is the 4K version. There is no logic chip on that one. I also made a version with a logic chip, but thats not on the picture.

Price depends on lots of things, especially on how much boards I would order. But I have made a rough estimation of a possible end-prize: 4K-Board: 6-8$ BS-Board without RAM: 8-10$ RAM board: 15-18$ The programmer would probably be about 30$ Yes, the flash chip is on board. I would like to have a completed design for the 2600 first. At this stage, its only a funny idea with a few prototype boards. But if I get the impression, that there are enough people who want such boards for the 7800, I don't see why that should be a problem ... Thanks, maybe I just need somebody to encourage me to go on with the above project. I will probably have to spend a lot of time until it is a finished usable product and I don't want to waste my spare time on something that nobody will ever really need ... Armin

I liked the cam very much

Hi, Some time ago I was thinking about 2600 PCBs that can easily be reprogrammed with one click. I mean not only the content of the EEPROM, but also the content of the logic chip. I thought of 3 different 2600 board types: * 2K/4K board with no bankswitching * board with no RAM that supports all kinds of non-RAM BS modes as F8,F6,F4,EF,E0,F0,UA * board with RAM that can support the Superchip modes and 3E,3F,4A50,E7,CV, FA etc ... I have also made a programmer to program the boards. The Krokodile Commander could be used to programm the boards that are pluged into this programmer. It is downloading the ROM content and the logic chip content with one click. I am a bit stuck now, because I have no feeling if anybody would really need these boards. I also don't know how I should continue with development. Should they be made such that they can be hand soldered ? Or should they be 100% single side SMD, because then they are cheaper to produce by third party companies. First, I very much liked the idea of this PCI edge connector, because its an easy way to plug something with lots of programming lines into one single connector. In addition the connector is for free - no parts needed But now PCI gets older and older and I was thinking about changing the connector to "PCI Express", because these connectors will probably be available for a much longer time. I added some pictures and it would be great if you could give me some feedback

Its a 4x4 register file with open collector output I am sure you already knew this. But seriously. You should not call a chip RAM just because it has a few registers inside. In that case you would also have to call the standard F8, F6, F4 bankswitching boards "RAM" boards. You can fit E0 in a standard PLD without needing a RAM chip, that is what I wanted to say

AFAIK, there are no boards available to homebrewers that support additional RAM. Yes, there are a few prototypes, like 3E or 4A50, but homebrewers can't buy or actually use them at this time. Don't mix it with E7. E0 does not need any RAM

I think Emulators and the CC2 clear RAM and registers before the Rom is started, but the 16K board does not ... CC2 and Emulators always start in bank 0, real boards start in a random bank. Do you think that could somehow cause your trouble ? Armin

I also think that would work

THX

Can you please look up the values of the two blue capacitors for me ? Armin

Hi, you have a HEF4024BP counter on that board. It is responsible for storing the game (bank) number. On that chip, there are outputs O0 to O4 which can represent a bank (game) between 0 and 31. I didn't check it, but O0 to O4 need to be connected to A11 to A15 on the Rom chip. The first step to be able to play 4K games would be to disconnect the Roms A11 line from this counter and connect it to A11 on the edge connector. If you don't do anything else, you need to toggle the power switch 2 times in order to be able to switch to the next game. There is no easy way to avoid that. I think you would have to rewire the counter such that O0 to O3 are connected to A12 to A15, which would probably not look very nice on the pcb Armin EDIT: There is a little problem now, because the A11 line on the edge connector is not connected. There is a pad, but no wire. If you look at the picture of the top side of your device, it is the 5th pad from the right side Its very hard (if not impossible) to contact this pad such that you can still plug the cart into the Atari EDIT2: If you want to use a 64K EPROM, you first have to make sure, that the pinout of the chip on the 32 in 1 is really the same as for a 64K EPROM. If this is not the case, you would probably have to make an adapter socket. Is there a schematic for the 32in1 available ?

The new run (Revision 1.1) of the Krokodile supports E7 bankswitching. That means you can remove HeMan, Burgertime and Bump'n Jump.

Try www.myropcb.com and get a custom quote for your PCBs. Should be cheaper there ... On the other hand I have never ordered there before and can't say anything about their service apart from that is seems to be quite cheap. Armin

Sorry for the delay, but we got a baby and now I am extremely busy. So I have very little time for the hobby. I can still test a few hours from time to time ... but it takes longer than I had thought and I have less free time than I had thought ...

These should be free for both reading and writing: $2E, $2F, 3E,3F, $6E, $6F,$7E and $7F I am not 100% sure what happens if you make a read access to these spots. But I am quite sure, that these spots are the only ones which COULD probably not be driven by the TIA if you read from them. I think for all other spots, at least some of the bits are driven ... Armin

Just a little bit more testing and after that they will be on their way ...