Total Noob needs help with booting up C2 - Linux

[DOHO23QC]

Any help would be appreciated! I'm sorry, this is my first experience with any of these products. We're trying to help a customer and I just need to make sure I know what to expect.
I have a C2, VU7+ and an 8GB Linux eMMC card. I have the boards connected properly together, with the eMMC Linux board connected to the socket on the bottom of the board. When I power it up I get some lines on the display, but that is all. Is that what is supposed to happen? Having the Linux board I was expecting some software to load, perhaps ignorantly, but nothing happens. I'm going in here very blind as their engineer is no longer there and he said the eMMC cards were supposed to be attached to a MicroSD card adapter, which nor we or our client has. So I guess my question is are these Linux cards basically blank until someone loads something onto them? Should I not be plugging the eMMC card into the eMMC slot on the back? Sorry I know you guys are above all this I'm just trying to figure this out.

[mctom]

Hello,

eMMC modules can be bought with Linux or Android preloaded, at various sizes, and for many Odroid products.
You may have bought (or been delivered) an eMMC module that has incompatible OS on it for whatever reason. Or if it has been used before, maybe the OS on it has been rendered unbootable due to misuse.

eMMC can be written to pretty much like SD card or USB drive. Except you will ned a eMMC card reader like this one:
https://www.hardkernel.com/shop/usb3-0- ... -writer-2/
This is probably what the former employee was referring to.

Then, you may write an operating system image on this eMMC module to start out fresh.

And the instruction how to write an eMMC card is here:
https://wiki.odroid.com/odroid-c2/getti ... _odroid-c2

[mad_ady]

Have a look at the color of the emmc pcb. The usb writer mctom referred to doesn't work with black emmcs if I remember correctly. Black emmcs were originally sold with C2.

Is your C2/emmc new or old? When you try to power it on with the emmc attached to the emmc socket, do you get a red (on) power led and a blue (flashing) alive led?

You can test if the board/vu7/psu works by removing the emmc, flashing a blank sd card (with etcher) with the latest ubuntu for C2 from Hardkernel's wiki and see if it boots and if it's ok.

If it boots and it's ok, you may need to reflash an OS on the emmc, but we'll worry about that when we get there...

[DOHO23QC]

Thank you for your replies. So the cards I have here are supposed to be new / unused, but I'm still confused if that means there is Liunx on them or not? They are the 8GB cards with the red square as shown if you scroll down a little on this page: https://www.hardkernel.com/shop/128gb-e ... 2-android/

Also here is what the original engineer who was working on this project has said:

"The EMMC cards snap onto a micro SD card blank/carrier. The ODROID C2 has a micro SD slot, and ODROID offered the Micro SD blanks to carry an EMMC card that snaps into the that and then can be used as the storage device for the ODROID C2 Linux OS and our touch screen irrigation controller.

The Linux OS was a customized Debian Linux. Once tested the entire Debian Linux OS, Applications, Scripts, etc was captured as an image. That image is then programmed onto either a micro SD card or one of the EMMC Micro SD card combos.

I'm not sure how many of the EMMC SD Cards were programmed. I know several were programmed, but mainly only as many as we needed for testing.
Many never had the image written to them, as it would take too much time to program them, knowing that the entire image would have to be replaced as bugs in the application were addressed, which would result in a new application version and new OS/App image.

There was nothing special about booting them up. As long as it had the OS on the SDCard, it just booted up. There were some special grub boot loader files that need to be present on the programmed SDCard that configured the ODroid C2 to support the TFT display. Without that, the screen would be blank.

Copying the image from one SD card to a blank SC Card required a disk imaging program, but I don't recall what disk imager was used."

[L67GS]

The SD card adapter is a real thing, but it's not intended to be used like that. The SD card adapter is used to program the eMMC module with another computer.
It sounds like he has some programmed there and you just need to try them and figure out which ones are programmed by booting them. Alternatively, you can program some of them, hopefully he gave you a copy of the image so you can program the rest, but if you can find an eMMC that boots, the image can be read from it and put onto the others. Download Balena Etcher and don't be afraid to ask questions here.

[mctom]

So if I understand you correctly perhaps all MMCs work but are not configured to support Vu7+ display, which I assume you are using. By default only HDMI output works. You can try plugging in an external monitor to confirm that.

Your engineer have modified some images to enable Vu7+, and some are left with factory defaults. As @L67GS suggested, you may want to try a few eMMC modules and find one that is configured by your engineer.

[DOHO23QC]

The SD card adapter is a real thing, but it's not intended to be used like that. The SD card adapter is used to program the eMMC module with another computer.
It sounds like he has some programmed there and you just need to try them and figure out which ones are programmed by booting them. Alternatively, you can program some of them, hopefully he gave you a copy of the image so you can program the rest, but if you can find an eMMC that boots, the image can be read from it and put onto the others. Download Balena Etcher and don't be afraid to ask questions here.

So what is supposed to be on these Linux cards when you get them? Can I see anything at all on a screen or do I have to program it first to see any data, no matter if I'm using the VU7 or not? Sorry this is confusing for me. When I think of an operating system I think of turning on a windows PC, Mac, etc and having an operating system pop up automatically.

[mctom]

This is not a consumer computer that does everything for you, that's what you needed that engineer for.

The default Linux image should boot to desktop accessible via HDMI monitor and USB peripherals, keyboard and mouse.
It must be configured to run through Vu7+ display, as I said, it is not enabled by default.

[mad_ady]

Of you plug in the emmc into a sd card reader (via the small adapter) into a windows PC you should see a small 128MB boot partition.

[L67GS]

If the previous engineer made it work then you really need to find one of the modules that he made work. It should have everything set up for the display.