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Update:

Main components ordered now. PCBs, display units and arduinos will be arriving during January and should be here latest early February.

I will check the smaller components needed tonight - I'll probably need to order some of them more as well.
 
Hello, I'm interested in one LCD unit if it isn't too late. Thanks
 
Hey there, finally got around to installing my LCD selector and for some reason it's not working. Wanted to see if anyone has any clues or advice as I'm stumped.

For the past year or so I have has the latest ST-V firmware and reset wire installed with a "piano key" selector and that works (and still works) fine. The LCD kit I'm using I believe is one of the ones Mitsu sold because the wires included in the kit are the same as the ones in his guide (I bought it unused from a forum member a year ago).

I have definitely followed the guide perfectly. I have 5v and GND tapped from the motherboard (from different pins, but they measure 100% fine). I have connected the extra reset wire to the multi cart and have checked the polarity and continuity of everything many times over.

I reprogrammed the Selector on OSX Yosemite and also Windows 7 without any issues after installing drivers and have tried the full game list and the joystick only list on both.

The issue is that the LCD boots up however when I select a game, I get a very slight flash on the Arduino but there's no reset and the games don't load.

My guess is:
1. The reset pins on the cart are somehow not working
2. The Arduino is faulty3. I've programmed it wrong

If anyone has had this exact issue, or has a remedy, or a guess, I'd love to hear. It's a super nicely made product and hopefully I can get it working!
 
Ok, it's so long time I designed the selector board and I don't have the schemas right now in my had, but reset signal should go through the 4066 chips under the lcd (4066 are just used as switches and it will ground the signal). If those are in sockets, swap the two. I did have few faulty 4066 ICs in one point, but I tested all the selector that I builded, still could be problem. If not that. it could be problem with the ground (or 5V). Selecting games etc works ok?

Can use take pictures where you took the 5V and GND and the other connections?
 
Hey @miisalo, thanks for your reply. The 4066 chips were indeed socketed and I changed them over with no success.

The actual LCD seems to be working fine, and when I do select a game it seems to send the process over, however nothing loads and nothing resets. I've also checked the orientation on the ribbon cable and tried every possibly way to connect it, just in case.

When using the dips to select games, it resets fine, so I know that reset line is working. The 5V and GND have also been measured (polled from different points, but feel free to check them on your motherboard too). I've used a multimeter to check continuity of everything, including the reset line from the cart->selector.

Here's some photos if you manage to pick up on something?

Thanks for your time.

stv1.JPG


stv2.JPG


stv3.JPG
 
Does the LCD display correctly? As in, it lights up and text is rendered?

I have no familiarity with the STV LCD however something you mentioned about the LCD dimming upon selecting a game could be a shortage of power issue or a short somewhere.

Take a video of what it's doing.
 
I never mentioned anything about dimming, maybe another user? The LCD theoretically works fine. The 5V line is fine too.

The light on the Arduino flashes when I select a game, however the lights to reset on the ST-V doesn't come on.
 
I think I misread your post, about the Arduino flashing.

I'm really not sure what's going on, not having first hand experience. Could it be a software issue, as in SD card setup? Does this differ when using an LCD?
 
The SD works fine as I use the same SD when using DIP switches. It's a reset issue most likely, possibly the faulty chips that @miisalo mentioned.

I have reprogrammed the Arduino on two different operating systems and it's fine. I grabbed them from the last roll up pack.

Was over at @xodaraP house yesterday and he was stumped too. My luck in this hobby is absolutely atrocious! :/
 
Hmm, no good idea at the moment either what is going here. I assume that you're getting the texts rendered on LCD normally and they show also correctly (also the scrolling function on long names).

Just to confirm something "stupid" issue. How long ribbon cable do you have between the selector (the large cable) and multi? Can you try to make some jump wires and do the dip switching from the end of ribbon cable? Does that work fine as well?
 
Yep, text and scrolling text is working fine on the selector.

The ribbon cable is exactly the same one I use with Mitu's remote piano key DIP selection switch with no issues.

If the 4066 chips are corrupt would the symptoms be the same as I am experiencing? If so, would these be a suitable replacement?

https://www.ebay.com/itm/10pc-CD4066BE-CD4066-DIP-14-Quad-Analog-Switch-Logic-Chip/142787018695

Or is there a check I can possibly do with a multimeter or EPROM programmer to check their health?
 
Well, of course the next thing is to measure if the reset line in the selector drops to ground. If you don't have scope, you can still measure it using multimeter. Just change the source code a bit and reprogram the arduino.

There is #define DELAY_RESET 100 in the source. That is delay in milliseconds, put something like 5000 and you have 5 seconds drop on the line, long enough to reliable see it in the multimeter. If the line does not drop to zero, there is probably problem with the board or the arduino. If it drops to the gnd, problem is the reset pin in the multicart.

If the line does not go low, there is also something you can try. Pin next to the reset pin was originally meant to be control line of relay to be able to (with extra hardware) control the ST-V board power, but that was done only in some of my prototype code. Current code basically uses it exactly like reset. So if there is a problem with arduino pin 11 (reset) or the pcb, you can just use the other pin. It is controlled by arduino pin 12 and the 4066 ic.
 
Just to update to everyone interested. It looked like faulty 4066 chip was pulling arduino IO pins low, so the selection pins were shit and also it had already burned the D11 and D12 pins. Could be bad batch of 4066 or voltage spike in 5V line shitting them.

So this is probably 4 dollars fix, new 4066 ICs and arduino from China.

One thing is that there is spot for capacitor next to the selector's power connector. Filling it with example 100-470uF capacitor will smooth the power input. Although taking 5V from anywhere but the jamma edge should be ok anyway. But if taking 5V directly from the jamma, it maybe should have example 16V 220uF capacitor and/or example 5.6V zener diode (although not sure if that zener would handle the current that bad psu would give with the spike)

E: I finally pulled out the schemas and here is bit of correction to above. D11 of course runs both reset pins, they are just using different units of 4066 chip. D12 is actually controlling the AUX pins, D12 could be ok.
 
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Thanks for your diagnostic call @miisalo, was not expecting that kind of service. Shows you care. Will order parts now! Glad it’s most likely a super easy fix!
 
If anyone has problems with selector, even bought from stt or secondhand, you can contact me and I'll try to help. I'm not here often, my spare time goes now more fixing retro computers etc and I tend to hang around other forums, but you can often find me from skype using name Miiikkas ( yes, there is three i's there)
 
Yeah, I called you here this time when this problem came up ;)
 
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