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rayik

Create and burn eproms for standard Jaguar 2 chip cartridges

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I believe they are 1uf. Digikey sells 500 for $35.

 

Actually have marked as 104 -> 10 + 0000 zeros -> 100.000 Picofarad -> 100 Nanofarad -> 0.1 Microfarad

 

This is the standard value of "decoupling capacitors" for the ic's. :)

Edited by santosp
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Hi all.

 

I know this is an old post but I need a bit of help. I'm new to all this but I have had a GQ-4X programmer for sometime but never used it.  I would like to try and repair a few of the games I have bought as some of the gold connectors have come of the cart.

 

My idea is to unsolder the 'HI' & 'Lo' eproms and solder them back on to a donor board.

 

But if I was to replace the eeprom Memory and/or 93C86 or 93C66 ram eeprom (as mentioned in the tutorial) what information do I need to write to those chips?

 

Thanks

Edited by namrood

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I went through the entire thread but didn't see it mentioned other than not requiring to be closed but what exactly are the C2/C3 spots for?

 

Some carts are closed and others are open and while it doesn't seem to matter in the end, would still like to know why or what the actual purpose of these are for.

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They're extra decoupling capacitors to stabilize the power delivery to the chips. I guess Atari found out that it worked fine without them and saved a few cents by removing them.

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Just wanted to post a helpful note on this thread about the EEPROMs (The save-game flash, not the big chips with the read-only game data).  There's lot's of info out there noting you should use the 93c46/93c66/93c86 chips as appropriate for the game you're building, but it is rarely noted (Found some references in the Rebooteroids public beta thread and a few other buried references) that there are two (Well, three. I'll get to this.) variants of all these chips: one with 8-bit and the other with 16-bit data organization.  Jaguar expects the flash organized as 16-bit words, as noted here: https://www.mulle-kybernetik.com/jagdox/cartridge.html.  Look at the datasheet before you buy, and be sure you're getting the right memory organization variant.  You can also get these chips in a variant that can support either mode depending on the value of an "Org" pin on the chip (Pin 6 on the 8-pin DIP Jag carts use), and this pin is floating on the Jaguar cartridge PCBs, so if you have one of these, just short pin 6 to pin 8 (VCC) to select 16-bit mode (Be sure that's the right value for your particular chip of course).  On the chips I bought, pin 7 was also a write-protect bit, and had to be shorted to VCC as well to enable writes at all, as this pin also floats on the Jaguar cartridge PCBs.  I just laid a bit of the capacitor leads that I snipped off after soldering those across all 3 of these pins and soldered it down to accomplish this.

 

As usual, one of @Matthias's tools is a huge help here:  If you have the right EEPROM and have it configured correctly, his EEPROM browser should auto-detect it and be able to manipulate the data on it.  If you made a mistake somewhere, it won't report that the chip type was "detected", and/or you won't be able to manipulate the data.  Of course, this only works if you have a BJL'd Jaguar, which everyone but me and a few other crazies thinks is heresy these days 🙂

 

Not a huge deal, but gave me quite a scare initially when I went to build some of those unpopulated fancy black PCBs from eBay after only recycling scrap cartridges from B&C in prior builds, which already had EEPROMs and capacitors on them, and wasn't getting any data saved!

Edited by cubanismo
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On 7/31/2020 at 4:43 AM, cubanismo said:

Not a huge deal, but gave me quite a scare initially when I went to build some of those unpopulated fancy black PCBs from eBay after only recycling scrap cartridges from B&C in prior builds, which already had EEPROMs and capacitors on them, and wasn't getting any data saved!

Just as a heads up, I have about 100 new black PCBs that I'll sell in lots of 5 for $20 shipped within the U.S. if there is any interest (the boards listed on eBay are not mine):

bpcb.thumb.jpg.ed9cefb806f0565ead3459157ed1d73c.jpg

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In theory yes, but you'd have to design a new PCB. It would also make cartridge access slower, which may cause problems with some games. I don't think anyone has ever tested it.

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is it possible to use 2 M27C322 eproms 42 pin- 4mb in place of 

  • 27C800 eprom (42 pin - 1 MB)
  • 27C160 eprom (42 pin - 2 MB)
Edited by CLS

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52 minutes ago, Zerosquare said:

In theory yes, but you'd have to design a new PCB. It would also make cartridge access slower, which may cause problems with some games. I don't think anyone has ever tested it.

is it possible to use 2 4mb eproms M27C322 i have a bunch of these on hand? I ordered the correct ones but they will not arrive for a while still.

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M27C322 EPROM chips appear to have the same pinout as the original ones, except pin #32 is A20 instead of /BYTE. So this should work, but you need to program the original ROM file contents into both halves of the EPROM. The programming software may have an option to do that, otherwise you can use a command prompt to create a suitable ROM file for your 4 Mb EPROMs:

copy /b input_file.rom+input_file.rom output_file.rom

Edited by Zerosquare
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2 hours ago, Zerosquare said:

M27C322 EPROM chips appear to have the same pinout as the original ones, except pin #32 is A20 instead of /BYTE. So this should work, but you need to program the original ROM file contents into both halves of the EPROM. The programming software may have an option to do that, otherwise you can use a command prompt to create a suitable ROM file for your 4 Mb EPROMs:

copy /b input_file.rom+input_file.rom output_file.rom

Thank You for this info. can you elaborate more on when you refer to " original rom file contents " ? .

Currently what I have done is used romsplit to split the avp.rom in 2 parts a HI and LO rom 2048kb each. What else needs done before writing files to eprom. Current name of files is AVP.HI & AVP.LO. Thanks in advance.

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You need to type this in a command line:

copy /b AVP.HI+AVP.HI AVP_HI.BIN

copy /b AVP.LO+AVP.LO AVP_LO.BIN

 

You'll get two 4096 kB files, AVP_HI.BIN and AVP_LO.BIN. Those are the files you should use to program your two M27C322 EPROMs.

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1 hour ago, Zerosquare said:

You need to type this in a command line:

copy /b AVP.HI+AVP.HI AVP_HI.BIN

copy /b AVP.LO+AVP.LO AVP_LO.BIN

 

You'll get two 4096 kB files, AVP_HI.BIN and AVP_LO.BIN. Those are the files you should use to program your two M27C322 EPROMs.

Thank you that worked great for me. 

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On 2/10/2021 at 9:01 PM, Zerosquare said:

You need to type this in a command line:

copy /b AVP.HI+AVP.HI AVP_HI.BIN

copy /b AVP.LO+AVP.LO AVP_LO.BIN

 

You'll get two 4096 kB files, AVP_HI.BIN and AVP_LO.BIN. Those are the files you should use to program your two M27C322 EPROMs.

Hello. This method is working good for all 4mb jaguar games Thank You. But did not work for the 2mb games. After I apply the copy command I am left with a LO and HI rom 2048 kb in size each. I tried copying these files x 3 to make them 4mb which made them the correct size. But they failed during the write/programming step. Any Ideas what to try? Thanks in advance

Edited by CLS

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On 2/12/2021 at 9:29 AM, Zerosquare said:

Try erasing and programming again. If the files are the correct size, there's no reason why it shouldn't work.

got it to work thanks. On a different subject do you think a sega genesis game pcb that contains two 2mb rom chips could be swapped and programmed with m27c322 eproms by using the same routine as the Jaguar games?  Creating hi and lo then matching the the correct eprom size? I Have not really seen much documentation on sega games with 2 rom chips.

Edited by CLS

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It depends on the ROM chips that are used in Genesis cartridges. If they're the same as those in Jaguar cartridges, it should work as well.

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On 2/10/2021 at 11:31 AM, CLS said:

is it possible to use 2 4mb eproms M27C322 i have a bunch of these on hand? I ordered the correct ones but they will not arrive for a while still.

Yes, it works.  You can use chips bigger than the files you are burning.  I've burned 2mb games onto two 2mb chips.  The burner I use starts the burn at address 0 and goes up from there.

 

You just do not want to do the opposite.  Burning 4mb games onto two 1mb chips results in a not working game.

 

 

***  EDIT 

 

Sorry, I did not comprehend what you were asking.  I'm not sure if those 4mb chips are pin compatible with the 1mb and 2mb chips.  Zerosquare does know and helped you.  Looks like you burned successfully by filling the entire chip. 

 

*** END EDIT

Edited by rayik
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