SAROO
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tpunix
RAM Cartridge emulation not working in any game!
Hello (again!),
As the title says, I get nothing (by that I mean every game will show their "RAM missing" error screen if/when they have one) when I try to load a game requiring 1/4MB RAM Expansion. I tried with and without exmem_1 and exmem_4 in the saroocfg.txt, but I always get the equivalent result of a RAM card missing.
Since for my previous issue #238 (TLDR I wasn't getting any BGM in game) the problem turned out to be corrosion down the path of one of the cartridge slot pins travelling through my Saturn, I was wondering if this time as well there are any specific pins responsible to "tell the Saturn" a RAM cartridge is present. Perhaps there are still broken lines on my Saturn that I missed and I could/should restore?! What do you recommend?
Cheers
If you have other cartridges to test with that would be a good way to rule out if it's the cartridge or the cartridge slot.
@TrekkiesUnite118 I don't have any other cartridges to test. If you take a look at my previous issue, you'll see that I am dealing with a Saturn that, at least then, had one cartridge slot pin that wasn't connecting all the way to where it needed to get (which I fixed by jumping a wire from the slot pin to the next junction after the signal interruption). In the same vein, if this is not a software/configuration issue, I would think there might be a similar problem with another pin losing it's signal along the way, since the slot itself is connecting to the cartridge securely. In my other post @tzmwx suggested to check pins A4-A5-A6, and indeed the signal wasn't getting all the way to where it needed to get for pin A5, so if anyone knows what pins on the Saroo are responsible for making the Saturn acknowledge the presence of a RAM Cart, that's likely where my troubleshooting should start. Hopefully someone can chime in with that info!
Cheers
There are many reasons that may cause this failure, such as the saroo card using a refurbished memory chip, or a problem with the Saturn circuit board or slot. You may need to check them one by one.
If you need a suggestion, you can check A47pin first.
There are many reasons that may cause this failure, such as the saroo card using a refurbished memory chip, or a problem with the Saturn circuit board or slot. You may need to check them one by one.
If you need a suggestion, you can check A47pin first.
Thanks! I'll check pin 47 right away! For your reference, my Saroo is supposed to be an "Elite" version, so in theory it should contain no refurbished components. I'll see what I get from pin A47 and report back.
Cheers
@tzmwx So I checked pin A47 and it seems to be ground point! I'm not seeing a problem there (unless it's not supposed to be a ground point at all!) and I'm able to verify continuity from the Saroo cartridge down to the front side of the Saturn motherboard (so, once again, the slot itself seems to be doing it's job). The only thing I see that may be out of place is that my Saroo has pin A47 and it's adjacent pin (A46?) in a separate layout, whereas I see pictures of other Saroo boards where the 2 are combined together (which also alters the actual pin number as well). Please take a look at the pics of my Saroo below to see what I mean (and in case you can spot something glaringly wrong!)
I can only count 48 populated A-pins on my Saroo, but the pic you attached in my previous post, indicated A67 as the last pin in the row, so I suspect that I've been probing the wrong pin due to this. For fun, I counted 20 pins (populated or not) back from the last one and tested that resulting pin. I get continuity for that as well down to the bottom-side of the Saturn: despite the fact that the corresponding top-side of that test point is underneath the Sega 315-5966 chip (IC5), I'm still able to grab back the signal on pin54 of the IC. Needless to say, I'm at a loss! Do you have anything else for me to try?
Cheers
Thanks!
Unfortunately, while I was waiting for a reply, I went ahead and tested that pin, as well as most of the surrounding ones that end in the IC5 and they all give me continuity. While probing around I found that I get continuity where I shouldn't (like across the contact points of CE38 which is an unpopulated cap - on all motherboard revisions from what I can tell) when the clock battery is plugged in. That doesn't sound right to me, but maybe it's normal. Is it though? I get that the battery will push some voltage to the motherboard, but should it cause a short on a component (pads of a component, in this case)? I haven't actually done any tests to run RAM-requiring games without the clock battery inserted, so maybe it's worth a try. But it would be nuts if they were to work somehow.
I am more at a loss than I was before!
But just to be clear, am I supposed to have any exmem_1M/exmem_4M in the .cfg for the emulation to work (if the hardware wasn't an apparent issue) or is it supposed to kick in automagically when everything works as expected (so no edit to the .cfg is required)?
Don’t edit cfg.
Suggestion: You need to confirm that all Saroo pins are connected to the pins of the Sega Saturn chip uniformly. Special attention: To avoid card slot malfunctions, it is necessary to test “Saroo pin - Saturn IC pin”.
or Find another Saturn and confirm if it's a problem with Saroo or Saturn.
@tzmwx you are an absolute legend! I saw your suggestion to add a 10K resistor on the Saroo board (issue #326) and yep, it solved my issue as well. I can't thank you enough! Cheers