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Home Arcade System

Ah, sure enough. That issue with the USB2DB15 causing all buttons to fire at once is what caused the coin error with the Atomiswave.
 
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Recieved mine earlier week, it came super hyper fast!(shipped saturday, arrived monday 8sharp at the door in france) looks ridiculous on the Retrotink 4K (lg c9, game mode, VRR FrameGen, min lag etc)

I didn't look too much at the new settings before recieving/buying the 5.0 HAS asaide from naming...now that I really looked into it, gotta say, I'm super impressed with the implementation and all those new ideas!

having the same issue with the usb2db15, but I'm sure we'll get to the bottom of the issue soon^^
 
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This morning I did a little investigation regarding the USB2DB15.

I checked it with my older HAS units, it worked just fine. Tried with the V5.0 - all inputs appear grounded, the adapter doesn't work.

I supplied power to the USB2DB15 via the DB15, but didn't connect it to any supergun or PCB game - it also didn't work, the LED wouldn't light up.

I opened the adapter and checked the voltages. The 3V3 regulator wouldn't get power.. so I checked the 2SA1213 transistor and found something weird:
Emitter - 0.05V
Collector - 5.14V
Base - 4.93V

How can you get voltage on the collector if there's no voltage on the emitter and the base is so high?

I checked the USB2DB15 schematic, voltage regulator/transistor datasheet, and board layout, and found the culprit:

schematic.jpg

2SA1213.jpg

usb2db15_PNP.jpg


If you look closely, the collector and emitter of the 2SA1213 are swapped places! The PCB uses an incorrect part library.

So why does the USB2DB15 work with older superguns, or at all? Because of the parasitic power supply effect. During startup, the USB2DB15 drains current from the JAMMA PCB game button inputs, just enough to power on the S-816 voltage regulator, which then saturates the 2SA1213 transistor. This way the whole USB2DB15 circuit is powered on.

Since the HAS V5.0 buffers all button lines, the DB15 inputs use 20-30K pull-ups. There's no way for the USB2DB15 to drain anything from such inputs, so it cannot start. Buttons appear grounded.

To confirm and test this for yourself, power on your supergun+USB2DB15 without any PCB game connected. The adapter won't turn on. Add a 1K pull-up resistor on whatever button output of the USB2DB15 to mimic the PCB game's button input - it will turn on just fine.

There are a few problems with this:
a) The USB2DB15 drains current from your PCB game's button inputs during startup. First of all, you don't want this to happen at all. Secondly, it can also cause damage to the microcontroller on the USB2DB15.
b) The collector and emitter are swapped places, so when the adapter turns on, the collector (output in this case) is shorted with the main 5V line.

@Raph_friend was made aware of the situation and I'm sure he will find a solution.

To HAS users (all versions), I don't recommend using the USB2DB15 until this is sorted.
 
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Thanks a lot for taking the time to look into this and doing the writeup like you did!

we found this out by chance and we'll make our setups safer because of it, mistake happen, and we grow more knowledgeable from of it👍
 
Greatly appreciate you two looking into this! Will definitely be implementing the fix once it's confirmed.
 
Thank you both for troubleshooting this so fast. I had just ordered a USB2DB15 maybe a week or two ago with the intention of using it with the HAS (once that is back in stock and I can place an order). Looking forward to receiving my USB2DB15, and awaiting the next in-stock notification for the HAS. This community is awesome!
 
bitkid said:
Thank you both for troubleshooting this so fast. I had just ordered a USB2DB15 maybe a week or two ago with the intention of using it with the HAS (once that is back in stock and I can place an order). Looking forward to receiving my USB2DB15, and awaiting the next in-stock notification for the HAS. This community is awesome!
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USB2DB15 isnt well designed first of all .

I think that USB2DB15 was never tested properly. It doesn't work without a PCB connected, so how did the author aka @Raph_friend the tests of overvoltage protection?
I dont think so he or other testers cranked up voltage on the PSU to 6V WITH a PCB game connected.
Who would do something like that?

imho the best usb to db15 released adapter is the one released by Undamned
 
there's one on Raphfiend's discord.

Mike said the 1st envisionned fix still wouldn't be electrically be safe enough of a fix to recommand using it with the HAS, I don't remember if it's the same fix of not.

I just wanted these adapters to let my casual friends play some 3s with their favorite controllers, a bluretro neo geo adapter and a dualsense will perform fine, fast enough and safer for that usecase👍
 
AlxUnderBase said:
USB2DB15 isnt well designed first of all .

imho the best usb to db15 released adapter is the one released by Undamned
Click to expand...
I am aware of Undamned but I saw this open source project (USB2DB15) and thought I’d lend them my support, at least financially. Once I get mine I plan to take a look at the firmware code and see if I can help improve 8BitDo support.

If the creator and community can resolve the hardware and software issues, this will be a great successor to Undamned.
 
JohnRambo'sKnife said:
I have one of the Raphnet Gamecube to N64 adapters. It worked for a whole 2 hours before it randomly started turning itself off after 30 seconds of use. Sent a support email and never got a reply. Can't say I am surprised.
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This is a different person, names similar though 🙂
 
JohnRambo'sKnife said:
I have one of the Raphnet Gamecube to N64 adapters. It worked for a whole 2 hours before it randomly started turning itself off after 30 seconds of use. Sent a support email and never got a reply. Can't say I am surprised.
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yeah not the same person. heard he had a good trackrecord thought, but that sucks :(
 
AlxUnderBase said:
USB2DB15 isnt well designed first of all .

I think that USB2DB15 was never tested properly. It doesn't work without a PCB connected, so how did the author aka @Raph_friend the tests of overvoltage protection?
I dont think so he or other testers cranked up voltage on the PSU to 6V WITH a PCB game connected.
Who would do something like that?

imho the best usb to db15 released adapter is the one released by Undamned
Click to expand...


The overvoltage test can be done using any DC source, you introduce the voltage and check the regulator's output pin. In some systems, the USB2DB15 won't work precisely because of the 5V regulation circuit's active protection.

It's strange that a member as senior as you are assuming things about the USB2DB15 without even testing it or delving into the project as a whole. Yes, we had a design error, and it can happen to anyone, from small to large projects.

Are you fighting for some winning side? Because I'm not; the project is Open Source, and my interest is for the community to gain a product that can be made at the lowest possible cost, regardless of where someone lives.

For example, I really like the UD adapter; I have one myself. But for me, living in Brazil, it was VERY difficult to get one at the time, and even now, unfortunately, it's a product that hasn't had updates for a long time.

The next version of the USB2DB15 will have some changes in the 5V protection system, both in the Open Source board and the donor version.

I am very grateful to the friends who believe in me and my projects and support me financially; it helps a lot to want to keep moving forward.
 
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