MiSTer FPGA Forum

I'm having a weird issue with NES SNAC using the Ultimate Mister SNAC-NES x2 Player. I am driving myself crazy trying to figure out the issue.

I have an original NES to test all my controllers with so I can validate they are working. Part of the issue is I think there is a tolerance difference on the 3rd party female NES connector used on the SNAC adapter that is different than a factory NES. Originally if I put some downward force on the NES male connector going into the female snac adapter it would work as intended. I though there was a bad connection on the circuit board so I went ahead and reworked all the solder joints on the snac adapter with no luck. Next I opened up the male connector on a standard NES 004 controller. The male connector has female pins so I crimped them a little to make a tighter connection. This resolved the issue with my NES-004 controllers.

Now with my NES Advantage NES-026 I get poor performance. I did the same trick crimping connectors but it behaves strangely. For instance holding the jump button in Mario will act like auto fire is on even if it's not enabled on the advantage. I'm sure it's not on because on the original Nintendo it's working as intended. Sometimes Mario will perform a full height jump and sometimes he won't doing a bunch of short jumps. Pressing multiple buttons at once seems to add to the issue. it's almost like not enough power is making it through the cable if that makes any sense.

One troubleshooting step I tried was to connect an extension cable between my NES Advantage and Original NES to make sure I was getting a good signal and the advantage could function this way with OEM hardware.. Next I connected the extension cable to the Mister SNAC port using my standard NES-004 and it worked fine. Finally I connected my NES Advantage 026 to the extension cable via the snac port and I still get poor performance. This test should validate all of the connection points are good.

It feels power related to me with he Mister SNAC adapter being more sensitive. I ordered new controller connectors on Ali express so I can replace them because they were definitely less than ideal. I'm tempted to in the mean time cut the female ends off my extension cables and solder to the advantage circuit board. Before I go scorched Earth I though I would ask on here.

The SNAC adapter I am using.
https://ultimatemister.com/product/dual-snac-nes/

My Analog IO board is set to IO6. Does NES need the other setting?

Any ideas?

Hello have you tested in both ports, same result?
If you see anything wrong with connector just contact me we fix.

If I swap the ports in the NES core to other port works a little better but is still off. I ordered another NES SNAC adapter from you Monday. It should be arriving soon. It's weird and I am not convinced its a bad SNAC adapter. As I said a standard NES-004 controller works with an extension cable and the advantage won't. The advantage works in the NES with the extension cable just fine. I'm just using the extension cable for testing purposes because I know the connections are good since I can test with real NES and Mister. I get the same results with and without the extension.

Are you connecting the SNAC-NES 2X device to MiSTer's user port with a cable? If so, is it very short? Can it be eliminated?

I ran into malfunctions on PC Engine SNAC because the cable was too long. I had to plug the PC Engine SNAC board directly into the MiSTer to resolve. (PC Engine controller reading is said to be especially timing-sensitive, which is probably why I saw the issue manifest with that system's SNAC.)

Yeah I am using the short 6" cable that was an option when purchasing the SNAC-NES 2X. I actually just fixed the problem by de-soldering the original 2 player NES advantage cord and replacing it with 2 of the NES extension cables I was using in the test. I am convinced the issue was resistance based because the connectors were definitely making a connection based on my testing from above. I wish I had replacement male connectors on order from Ali Express but they are weeks away. I ordered these. Then I would know if it was just the connector.

https://www.aliexpress.us/item/32568028 ... _shipto=US

It's an extremely easy solder job to replace the cords on these old controllers and I have a feeling most people having SNAC issues with NES saying this controller works on a OEM NES are related to mostly the connectors or wires being bad. As I learned just because you tested on an NES it works doesn't mean it will work on the SNAC port. None of my working controllers worked when I first used it including the light gun, standard controller, and now the advantage. The light gun and standard controller were fixed by opening up the connector with a screwdriver pushing in the 4 tabs and crimping the female pins a little.

The extension cable I cut the female end off was this one. 2 of them can even slide through the little rubber grommet on the Advantage so stress won't be put on the circuit board. I also added a tie wrap to wires on inside right before the grommet to make it even harder to pull the cables out.

https://www.amazon.com/dp/B08BF8D17K?ps ... ct_details

I imagine you can use these with any controller. FYI the color code of the wires is difference and I tested with a continuity tester. Here is the color code at least for the Advantage. I have a feeling Nintendo may have used the same colors for other controllers too.

NES Advantage Wire Color - Amazon Extension Cable listed above
Orange - Yellow
Red - Orange
Brown - Green
Yellow - Red
White - Blue

Brown and Black from Extension cable not used with Advantage and probably not with standard controllers either. Light gun may use different pins.

I purchased a load of NES controller ports sockets from Ali Express a year ago or so and the quality was very questionable.

The pins in the socket were not of uniform thickness and caused issues with controllers

Wave wrote: ↑Thu Feb 23, 2023 2:49 am

Are you connecting the SNAC-NES 2X device to MiSTer's user port with a cable? If so, is it very short? Can it be eliminated?

I ran into malfunctions on PC Engine SNAC because the cable was too long. I had to plug the PC Engine SNAC board directly into the MiSTer to resolve. (PC Engine controller reading is said to be especially timing-sensitive, which is probably why I saw the issue manifest with that system's SNAC.)

The dedicated PCE SNAC fix all that issues regarding extensions, works with Turbo Mode and 6 button gamepad.

I'll try the male connections from Ali Express. If they don't work I'll stick with cutting end off of extension cables when needed. I think the ones I ordered have to be the same length though since the pins come loose and I have to crimp and insert them. I would love to salvage the Advantage cable though because that is a double wire since the advantage has a 2 player switch. Not the end of the world either way.

Hi! I have similar issue with one of the aftermarket NES controller from Aliexpress with Turbo buttons! Is there any way to fix this?