HDMI cable causing phantom power back to Kawari (large) about vicii-kawari HOT 21 OPEN

It sounds to me like your monitor is sourcing current which is not supposed to be the case for HDMI sinks. The spec says only display sources are supposed to provide current. There is a load switch on the board that prevents back-feeding. This case would have powered the 64 on the previous version of the board which is no something you want. But even though I added the load switch, it could be the board is not playing nice with your monitor for some reason.

Is your monitor's HDMI port MHL compatible by any chance? It could be that your monitor does not detect the 5V on pin 18 and starts providing its own current to power the attached device. Can you share the model # of the monitor? I'm not sure why swapping out the cable would make a difference though.

from vicii-kawari.

Asus VE248H, only lists HDMI 1.3 as the port, no extras. It's a standard computer monitor.

Here's a link to the manual.

https://dlcdnets.asus.com/pub/ASUS/LCD%20Monitors/VE247VE248VE249/VE247-VE249_English_V1.pdf

I've put things away for the night/weekend, but I'll think on if I have a way to pinout the cables later.

from vicii-kawari.

I've ordered hdmi breakout boards and will be able to find out the different cabling.

from vicii-kawari.

I did a little more testing tonight with a small micro hdmi male to standard hdmi female adapter, along with the 2 full cables.

Link to the adapters.
https://www.amazon.com/gp/product/B00JDRHQ58/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

All 3 of the following monitors show the phantom power.

Asus VE248H, Westinghouse L2410NM, Samsung LS27E310HSG/ZA.

Voltage across the led when fully powered is 1.8v
When phantom powered it's 1.5v which is also present on the 3.3 regulator output.

Phantom power persists even when the kawari is removed from the motherboard.

So 2 out of 3 cables are showing phantom power. What cables are you using?

from vicii-kawari.

Also, is this something that may be involved?

https://support.xilinx.com/s/question/0D52E00006hphYzSAI/unintentional-backpower-spartan6-through-io?language=en_US

from vicii-kawari.

from vicii-kawari.

The one cable I have that doesn't feed back is a generic one I've had for awhile. Can't remember where I got it.
I work for a computer shop, and we have gotten all kinds of hdmi cables over the years.

from vicii-kawari.

Would you be able to check the HDMI connector for solder bridges? I'm wondering if there might be a solder bridge on the back pins of the connector somewhere. It's hard to tell sometimes. But perhaps there is a short on the receptacle end and older cables don't matter because that pin may not be connected. But newer cables might have a connection to the monitor port which may explain this. Just a thought.

In the meantime, I will try to reproduce it here.

from vicii-kawari.

Just looked under the microscope, and didn't see anything. But it's a very hard thing to see on that connector.
My breakout boards will be in on friday, maybe they will be able to show me a short.

from vicii-kawari.

Edit... Removed garbage image..

The breakout board was horrible for pinouts.

from vicii-kawari.

from vicii-kawari.

Ok, getting out a needle and figuring out the actual hdmi pinout for the break out boards, the cable that doesn't feed phantom power has the following pins NOT connected.

2, 5, 8, 11, 14, These are the grounds for TMDS 1,2,3 clock, and then HEAC -.

from vicii-kawari.

And just for sanity check, using a one to one cable, I see that 2,5,8,11,15 & 19 are connected together on the Kawari board, correct?

from vicii-kawari.

Also, if the VGA connector is also connected to the monitor along with the HDMI, the cable that works HDMI only still provides phantom power.

from vicii-kawari.

from vicii-kawari.

Asus monitor goes into standby mode, but never kills the pull ups.
Westinghouse has no standby (Ancient, but has Composite, Svideo, Component, VGA and HDMI.

from vicii-kawari.

I went and grabbed a Acer V227bmix and a Asus VE228 from my stock to try.
The Acer does power off the pull ups after it goes into suspend, but the Asus doesn't just like it's 24" brother.

But for using the monitors, none I have tried allows for scaling the HDMI input, but all allow for the scaling of the VGA input, so vga is looking like the winner for a proper display.

from vicii-kawari.

It looks like whether this happens is going to be at the mercy of the monitor. If the monitor times out and drops the power, you can boot by just waiting a few seconds. Another work around is to use an HDMI switch. My switch does not power the core even when it is the display selected by the switch. So it looks like the work arounds are:

1> Wait for monitor to give up its scan for a signal
2> If 1 is not an option, turn off the monitor before powering the C64
3> If 2 is not an option, use an HDMI switch that does not power the core
4> If 3 is not an option, use an HDMI switch and temporarily switch to a different input

Unfortunately, the proper way to deal with this is to add an HDMI buffer IC which will add more space/cost and potentially trigger license issues. I"ve read that even if you use an IC that is licensed for HDMI, your device still requires an HDMI license. (Kawari uses only DVI protocol and no HDMI). But I wanted to stay clear of even a hint of any HDMI license issues.

Do you think these workaround are acceptable? If not, I might just drop the HDMI connector entirely from my design as it is proving to be quite a pain.

from vicii-kawari.

IMO, I would drop the DVI support, since you don't have a easy way to force 4:3, and maybe just concentrate on RGB/VGA and maybe optional component output instead of the DVI.

Or different firmware to pick between RGB and component.

There are so many devices like the RetroTink, etc, getting the highest quality out of the 64 we can while keeping the correct aspect ratio seems to be the way to go in my book.

The 15K RGB out looks great on my Sony PVM.

from vicii-kawari.

I opened a poll on the discord channel. So far people like the idea of easy HDMI connection even with the boot issue and sometimes lack of perfect 4:3.

BTW: Did you have any issues closing up the 250466 machine with the kawari installed? Someone is asking on the discord and I don't have one to try.

from vicii-kawari.

I have a few loose boards that I've throw in a breadbin case to test.
I haven't tried any slim cases at all.

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