Forums » Hackberry A10 » Discussion » HDMI screen won't take HDMI signal from Hackberry A10


Screen: Gechic On-Lap 1302

This screen doesn't work with Hackberry A10. The screen says «No signal. Source: DVI», as if it wasn't connected to anything. Ftr, it does NOT have a DVI connection (only HDMI and VGA, in the form of a cable of each kind that plug into a common proprietary connection to the screen).

Troubleshooting: It's not the Hackberry, as it works with my TV via HDMI (with Android or Ubuntu). It's not the screen or its HDMI cable, as they work with my tv receiver, and worked wonderfully with Raspberry Pi (before I toasted my RPi). It's not the screen's power draw from the Hackberry, as I can power it separately from a usb phone charger. It's not the screen's settings, as they are fine with other HDMI sources. Actually, I don't think I've ever managed to get into the settings (the touch interface must require the touch of an elephant, or I'm not getting it).

My suspicion: 1) The On-Lap 1302 product page vagely mentions «supports DVI signal through HDMI port» (which would be totally okay in itself) but does that mean there's something it does NOT support? 2) Other forumers are struggling with HDMI→DVI adaptors, does that mean the Hackberry (or Allwinner A10?) uses some special HDMI signalling that is not backwards compatible with DVI?

=> Isn't HDMI always compatible with HDMI?

It sounds like the display is actually a DVI-based screen that happens to have an HDMI connector as its interface. I could never get the Hackberry to work with any of the DVI displays that I have tried plugging it into, but it works fine on my HDMI-based monitor that actually works with the HDMI signal directly. (For the curious, it's an Acer S230hlabii, which I do not recommend because it exhibits visual artifacts from only updating half the pixels per scan.)

I thought there was a thread about this somewhere in regards to the Cubieboard. I lost the link to the discussion, but I think it has to do with DVI not supporting the YCbCr-based signal that the Hackberry carries, instead of the RGB signal that DVI-based monitors expect.

In reply to anordal

Hey guy's i have the same problem, i got my hackberry 3 or 4 months ago, unpacked it and testet it, ! it worked fine on the HDMI port, at my 24" screen and on my tv with HDMI too. But now on both devices i get "no signal" ...! if i use a composide cable it works fine on the 3.5mm plug ! if i plug in the HDMI cable, the hackberry say's switching to HDMI mode, but still nothing happens

i can use the component cable but the quality .. no comment xD

so what can i do ? or what is the problem ? is it just a wrong config ? or is the HDMI port broken ?

THX for help


Thanks for the answer hiddenmaverick!

The HDMI YCbCr/RGB issue was mentioned for the MK802: https://www.miniand.com/forums/forums/discussion/topics/not-dvi-compatible?page=2

@Anitheus Looks like Allwinner is supporting only the wrong colorspace, meaning no compatibility with computer screens! Extremely disappointing, I say — can't use the screen I bought for the purpose (laptop project). If it's a hardware issue, there is no hope, but right now, it seems noone knows why.

What we can do? Buy another Raspberry Pi, that's what I will do. And throw Allwinner on the campfire.

hello again,

in my case i'am now sure the hdmi port, or the gpu is broken ! my tv seems to be a killer, tried it with an HML converter ( smartphone to tv ) worked for five times and now the hml converter is destroyed...

so i think my tv is landing in a campfire soon xD


In reply to anordal