PAL SNES lifted pin 111. Flickering black and white video

Hi. I have a 1 chip PAL SNES and I lifted pin 111. I have a switch currently which connects 5v to pin 111 or gnd to 111. When I set it to 50hz it works but when I set it to 60hz it just jumps in black and white. Is it true I just need to use an RGB cable? Also I seen a video someone playing the PAL super Mario world game but they we're allowed to switch it to 60hz. Do I just need to lift leg 4 and do the region lockout mod to run it? Also does doing the region mod fix the screen problems in 60hz or is it because I have a different crystal and just need an RGB cable. Thanks.

Do you know whether your TV can decode PAL60 video?

Someone asked this question of an older 3-chip PAL SNES, but for them they started with an NTSC SNES and had problems switching to 50Hz modes (as a result, said SNES was always emitting NTSC color modulation regardless of vsync rate)

Yeah it's a CRT I'm using. It handles 60hz on the GameCube etc. I can try make an RGB cable and see if that's the problem but at the minute I only have one 3 way switch. If I wire pin 4 to the middle of the switch with pin 111 I'm assuming that's a bad idea so I'll have to get a second switch before trying this. I was thinking if I use one switch I'll just have pal 50hz or region lockout mod 60hz without the option to use pal 60hz but I'm thinking them 2 wires crossing just seems like it might go wrong.

"jumps" implies something funny with vsync also.

Can you see some kind of diagonal or checkerboard lines in the black-and-white video?

I'm seeing the image3 or 4 times across and moving down slowly with black horizontal lines. Here's a picture of what it looks like.

https://s14.postimg.org/7fbia5nb5/20180128_020507.jpg

Oh, man. Uh, there's no hsync lock there, Looks like it's not even drawing at the correct 15.7ish kHz hsync rate.

The NTSC SNES starts with a 6×NTSC (i.e. 39.375MHz × 6 ÷ 11) crystal and derives everything from that; in contrast the PAL SNES ultimately operates at PAL×24÷5, from whatever provenance. (Nocash says there's a bit of silicon to generate both this clock and the actual PAL colorburst frequency at the same time in the 3-chip model)

If changing that pin means that the SNES now expects a ≈22MHz crystal instead of a ≈18MHz one, that could explain the symptoms?

Any chance you could listen to the video output and check if there's a conspicuous whine at 13kHz instead of the intended 15.6kHz ?

Yeah it makes a high pitched squealing noise actually. So the problem here is going to likely be that I'll have to somehow source an NTSC crystal to complete this mod?

Do check the specific frequency. A random PC microphone and some software that can generate a spectrogram (like Audacity) would be sufficient. (If you had an oscilloscope that'd be even better, but most people don't)

It seems to be picking up 13khz and 18khz when I switch it to 60hz along with the 15.6ish khz. When I switch back to 50 it picks up just the 15.6ish one on it's own as expected.

Huh. Yeah, ok, based on the available evidence my best guess is that it needs a 6xNTSC crystal instead of a 4xPAL crystal.

4.43361875 MHz × 4 ÷ 4 ÷ 341 = 13002Hz
13002 Hz ÷ 262 = 49.625Hz ?

You said you usually have a vertical lock, just not a horizontal one?

This is exactly what I'm seeing https://youtu.be/mBBDJNZI9Ns

Ok, no vertical lock but it's certainly close to whatever frequency the TV naturally wants to run at.

The scanline-to-scanline drift moves to the right, i.e. it's too slow, so that makes me a little more confident about the choice of clock.

I'll have a look at the FC twin I have in the morning since the snes portion of that is broken anyway. It's a 60hz nes with bad colours basically. I'll see if it has the right crystal but either way I think I'm gonna need a switch with 6 connections so it can choose the xtal and framerate together. I don't have sound either but I think this tv just doesn't have sound unless the picture locks on.

Are you using the RF modulator or the standard A/V port? If the latter, you should be able to plug in the red/white cables into an external sound system, or even headphones.

Krzysiobal found that he was able to leave one side of both crystals permanently attached in a region-switchable famiclone.

Yeah I have pc speakers that take the rca connections so I'll try that first thing tomorrow. I don't even mind if I have to break the FC twin it's basically very cheaply made anyway and it's one of them crappy black spot IC's it uses that you see in extremely cheaply made electronics.

To switch single chip machine between 50 and 60Hz you must also change the master clock. 21.47727MHz for 60Hz and 17.734476MHz for 50Hz.

This actually seems to have 3 crystals in it. As I said the snes portion won't work in this FC twin anyway but I have no way to even measure these crystals. They're labelled RJH21 4772A and one says RJH24 576A

https://s14.postimg.org/7ejxzfrsh/20180128_094527.jpg

I figured out it's the right crystal but through av there's no red colour. I probably just need to use RGB but that's ok. I lifted the pin for the region mod also but it doesn't seem to do anything u less maybe it's only for certain games.

Ok so sorry for all the posts but I have everything ready now. I have resistors and a dpdt switch along with a second switch for the region mod. There's just 2 more things I need to know when somebody gets a chance.

1. Is it normal for the snes to still work while pin 4 is not connected and should I still connect it to a switch that goes to 5v and gnd?

2. Do I need to lift pin 9 on the RGB chip also to fix the colour in composite?

I don't mind the second one too much as long as RGB works but just wondering does it need to be done.

Thanks for all the help so far also. I would have been completely lost otherwise.

All input pins should be tied somewhere rather than left floating, it will remove chance of mysterious mode toggilng Happening later. You can explicitly tie it to GND or VCC, or just one of them with other handled by a pull-up or pull-down resistor, allowing to have one less wire go to the switch.

Switching the pin 9 on the encoder is advisable, there will be TVs that do not like PAL60 or NTSC50. This will not affect RGB.

If I do that like just link it to GND for example does it still switch regions when I switch between 50 and 60hz? This one chip model is so different that it's confusing me.

Pin 9 to the middle of a switch going to 5v and gnd also?

Sorry for all these questions I just want to at least do it right since I already went this far.

Switch is what ties the signal to either VCC or GND, a signal should not be left floating (i.e not connected anywhere). You can use a pull-up resistor on the signal line to provide a "default state", which also allows you to use only GND on switch side, no need for an additional VCC wire. Signal will go to middle pin of a switch, outer pins connect to GND or VCC, or just GND on one side when pull-up resistor is used. Use whichever is most convenient.

I forgot to lift pin 9 but after doing all the soldering and all the hassle I had I think I'll just leave it at least for now anyway. Thanks for the help. I probably should have just done the switchless mod but whatever it works anyway. I'll be using RGB because it looks way better.

My new 4K tv doesn't have scart but in my opinion you have to play these older consoles on a crt or it's just not the same. Input lag is one thing but it usually looks horrible too and just doesn't feel the same. It's better to use a CRT for them