How to setup 27c512 ? about atari-xe-multicart HOT 31 OPEN

Hello there ;)

Finally, I finished soldering my board and I also have questions.

I also want to use the w27c512 chip, but I have questions about how to place the chip in the socket?
Unfortunately, the links to the photos of the topikstarter are no longer available, and the answers did not bring clarity.

Since it is correct to place the chip in the socket, from the beginning of the contacts or from the end?

Here my photos: https://imgur.com/a/wgHHUli

Also, do I understand correctly that you need to insert the cartridge into the atari with the chips down?

I absolutely don't mind if you add my photos to the project so that in the future people can get visual information right away.

Thank you very much in advance!

from atari-xe-multicart.

Hi,

The setup looks good, that should result in a 512k multicart and assuming that the bin file begins with the game selection firmware it should work on any XE-series machine. Not sure about XL as these probably use a slightly different OS ROM, which the game selection firmware kind of takes for granted right now.

Does it display anything when you put the multicart into the console? Can you try burning an 8k game to the very beginning of the flash chip, so that it acts as the selection firmware? If that does work it's probably the firmware that needs some adjustments. Unfortunately, I don't have any non-XE Atari machines to test in on :(

You can also try fiddling with the jumpers, basically any setup should at least display the game selection firmware, so if that doesn't change anything it's probably something different.

Also, a silly question - are you inserting the multicart into the console correctly? It should go there component side down (a bit counterintuitive, I know).

from atari-xe-multicart.

I just realized that the staged photo is misleading as it looks like the component side goes on top, not the bottom. I'll make that explicit in the README.

from atari-xe-multicart.

Hi again,
Thank you firstly. As I said, I tried & tested it on ATARI 800XL & 600XL but not XE series :(

I burned 8K rom file (for Your menu.rom and a few 8k game rom file) on M27C64A. I tested it all. When I put the cart into the console, It displays like my uploaded photo image.

Image Links:
I. http://i68.tinypic.com/34ye83d.jpg
II. http://i63.tinypic.com/289g552.jpg

If I insert the multicart into the console wrongly, It boots BASIC, It says READY. :)

As a result should we say that it does not work for XL?

from atari-xe-multicart.

That might indeed be the case here, unfortunately.
It's hard for me to say what might be the issue here without hooking up a signal analyser to the cart, so I can't recommend anything other than maybe reflowing all connections on the cart PCB and cleaning the cart slot contacts on the console. I did get a lot of odd behaviour resembling your second picture in the previous reply when building this thing - the problem was bad connections between the thin PCB of the multicart and the cart slot on my Atari. So maybe that's indeed the case here? A 1.6 mm thick PCB should be fine, but maybe you've ordered 0.8 mm?

from atari-xe-multicart.

Looking at my old version in the picture in the README I actually went for using an HC series 74373 latch instead of a TTL one. I don't really remember that changing much, but since I left out any pulldowns on the extra address lines comming from the 74HCT373 it might be the root cause of the issue - the lines aren't all zeros making it select one of the ROMs already. Potentially a non-existant one or the wrong half of one of them. Maybe try changing that for a 74HC373 instead? I'm also using a TTL 7408 and the transistor is a BS107.

from atari-xe-multicart.

I have ordered 1.6 mm thick PCB. I will reflow all connections on the cart PCB and cleaning the cart slot contacts on the console.

I will try 74HC373. But You said that transistor is a BS107. It is BS170, isn't it?
If I change from 74HCT373 to 74HC373, Should I use TTL 7408 and BS107?

from atari-xe-multicart.

On the working cart I have a 74HCT08, 74HC373 and BS107, but the BS170 should do equally fine. I don't have a 74HCT373 on hand right now, so I can't really test if that causes the odd behaviour. I suppose it would be wise to add the pulldowns to the design regardless.

from atari-xe-multicart.

Hmmmm. I also will try 74HCT08, 74HC373 and BS107. I'll return feedback to you.
In addition, Is LS (74LS08, 74LS373) slow or compatible for this project?

from atari-xe-multicart.

LS should be fine. :)

from atari-xe-multicart.

I tried LS but it does not work. :(

from atari-xe-multicart.

Then the HCT probably won't work either. That's a pickle, as I can't really reproduce the problem on my end, so I can't really debug it. All I can think of doing is hooking a logic analyser to the extra address lines to verify wether the transitions are correct.

from atari-xe-multicart.

Hi, sorry for the late answer.
The chips supported are conformant to the JEDEC pinout standard, meaning you can align them towards the bottom of the socket (away from the notch). Then you have to set up the jumpers accordingly (it's described on the README) in order to supply the power to the chip.
If you're unsure how to align the chip, you can follow the pinout on the biggest one supported (see this datasheet) and align the GND & Output3 pins on your chip with the socket.

from atari-xe-multicart.

Oh! Thanks for anwser! As I understand it, this is the same principle as in the programmer. There, too, the chip is aligned to the bottom of the connector.

Like on this photo → https://imgur.com/a/GS2mEZp

Pins set for 512Kb:

Memory chip size | JP1 | JP2 | JP3 | JP4
512k (27C512)    |  X  |  X  | UP  | DOWN

The question of how to correctly insert an atari cartridge also remained open. Is the previous photo correct?

Location down the chips → https://imgur.com/a/wgHHUli

from atari-xe-multicart.

Looking good! According to the README the component side is supposed to face down when inserted into the console. I'm inclined to believe that's correct :D

from atari-xe-multicart.

Unfortunately, the board didn't work :( Atari starts polling devices and freezes. If the cartridge is removed, atari start BASIC.

How i understand that when start the cartridge, there should be no device polling. Just starts the code from cartridge?

from atari-xe-multicart.

Yup, it should run the cart code instead of basic. I had some contact issues initially, because my PCB was too thin. You might wanna check the connections on yours. In my case, either bending some of the Atari edge connector pins or slightly tinning the contacts on the multicart was what did the trick.

from atari-xe-multicart.

Ah, here's the thing. Thanks a lot. I'll check the contacts on atari.

from atari-xe-multicart.

Hi, I have the same problem. I have an Atari 800 XL. I made a XE Multicart cartridge (27C512), I did everything according to the instructions, but my menu doesn't appear and I just run basic READY. :-(

from atari-xe-multicart.

Hi @gadiscz , that's unfortunate. I can suggest checking that the cart PCB makes good connection to the cart connector on the Atari. I had some problems with thin PCBs (0.8mm) not making a good contact and that manifested in various weird ways (mostly the BASIC prompt appearing though). A more suitable thickness would be 1.6mm, but you can modify the cart by tinning the connections slightly (just enough so they reach the contacts on the Atari).
Other than this mechanical issue I can't think of anything that could cause this, or that can help. :(

from atari-xe-multicart.

Unfortunately, cartridge has not start. I cleaned the contacts on the atari side. Distinct black traces of oxides remained on the paper. I ordered the board on allpcb.com and its thickness is really 1.6mm.

The ROM chip is working, it can be flashed and read without problems.

There are only two questions left, these are the other chips themselves, perhaps the Chinese sent low-quality components. And secondly, capacitors near chips confuse me a little. If I understand correctly, this is for more stable works of chips and capacitors should not be polarized?

Judging by the scheme, they can be both polarized and fixed. I use fixed.

from atari-xe-multicart.

I have a thickness of 1.6 mm. other original old cartridges work for me. I will try another EPROM size

from atari-xe-multicart.

I will try another EPROM size

Hmm... maybe that's really the problem. Looking forward to the result :)

from atari-xe-multicart.

If I understand correctly, this is for more stable works of chips and capacitors should not be polarized?

These are bypass caps, they indeed make for a stable power supply for those chips. You can use small-value tantalums or ceramics for these, the values don't really matter so anything from 1nF to 100nF should be good enough.

I have a thickness of 1.6 mm.

Hmm, then it's going to be the multicart indeed. Please check the 7408 next, that one is used to determine whether the EPROM should be enabled and which address to choose for it. If that works correctly then it means the EPROM is not floating, so it should at least execute something other than BASIC (even if it's some garbage).
Another thing to check is the MOSFET inverter on the CCTL line, that controls the bank selection. If that is stuck in either state (due to a different pinout of the part you used for your multicart, or some such problem) it might cause the data lines to be pulled high or low and that might mess it up (although I would expect it to execute some garbage instead of BASIC if that were the case).
Lastly, it might be the software. AFAIR, I'm doing some "sanity checks" to figure out if the console was soft-rebooted to start a new game - poking around the OS memory to check some values in memory. Perhaps that is triggered by the menu immediately due to a different OS version than the one I implemented it on. You can try programming the EPROM with just one game at the very start of the EPROM (so instead of the game selection menu) and try the multicart this way. If that's it, then we'll need to figure out how to update sanity checks for different OS versions.

from atari-xe-multicart.

Ok I'll try to upload one file. How do you convert .xex files that are different size 6-40kB to the correct size (8-16kB)?

from atari-xe-multicart.

How do you convert .xex

No no! XEX file will not work, you need to take a ready-made BIN file, not even CAR (it has a header at the beginning of the file)

from atari-xe-multicart.

I report. I flashed one image of the Boulder Dash cartridge in W27c512 - the result is the same, that is, none.

Then I found very old chips with ultraviolet erasure 27c512, 27c256 and 27c64. I did not try to flash them, since they must first be washed with an ultraviolet lamp. I just plugged it in for a test, setting the jumpers according to the diagram.

256 and 512 the result is the same as with rom image. But 27s64 began to flickering the screen, then purple then black. That is, it looks like something is still trying to start.

A little later I will try to erase the chip with ultraviolet light and re-flash it.

from atari-xe-multicart.

I also tried to run without a ROM, the result is the same, nothing happens. It is very likely that some components of scheme do not work and the ROM chip does not turn on correctly.

I would venture to suggest that for 27c64 such switches are not critical and it is trying to start.

from atari-xe-multicart.

What program do you use to convert xex to rom? Do you need to enlarge a file that has 15kB to 16kB?

from atari-xe-multicart.

I have this working but only with their file...

https://www.pcbway.com/project/shareproject/ATARI_800XL_MULTI_GAME_CARTRIDGE__4_x16KB_.html

from atari-xe-multicart.

finally i bought an atari 800XE but the problem is not solved :( still my bin files don't work. i have different eproms do you have a working bin file for test?

from atari-xe-multicart.