Running the CM3 Board with a NON-LITE CM3

[almighty_malgus]

Howdy from Texas yall,

Just finished putting together a Boxy Pixel build and noticed the rpi board I ordered was a non-lite version of the CM3 board.
It has 4 gigs eMMC and I had no way of flashing it without purchasing another IO board to flash it.

This was frustrating as the website kind of sends mixed signals (though, it is ultimately my fault for not reading more carefully) so I sought a way to flash the modules I had ordered since everywhere I checked for a Lite seems to be out till next year.

Why does the CM3 board only use the lite versions of the CM3 module? I think it has to do with the pin out pointing to the SD card and not the on-board eMMC flash.
I found a few threads here stating that you can alter the board physically to get it to work but that's a pain.

Through some poking around, I found you can flash the eMMC of the CM3 via the Freeplay board itself.

Steps to flash eMMC of CM3 module for use in Freeplay CM3 board:
- Slot CM3 into powered down Freeplay board
- Install these drivers for Windows (https://github.com/raspberrypi/usbboot/r..._setup.exe)
- Once those are installed plugin your Freeplay board with the CM3 slotted to your Windows Machine
- Turn on the Freeplay board
- You should see windows "detect" and setup a device
- Once this is done run "RpiBoot" (installed when you installed the drivers above)
- You should see it start to spit out some text and then you should see the board show up as a drive in windows
- You can now use Rpi Imager or a similar program to flash the image to the eMMC


I did this with my stock CM3 and it seems to have worked out just fine save for the limited 4gb of storage.
Hope this helps! DM me if you have any questions!

[Flavor]

Nice writeup, almighty_malgus! 

I have a question about this step.
"- Once those are installed plugin your Freeplay board with the CM3 slotted to your Windows Machine"

Did you use something like a "USB A to A" cable to plug into a USB-A port on your computer or did you plug in to a USB-C port on your computer using a "USB C to A" cable?

Now, for your question.

"Why does the CM3 board only use the lite versions of the CM3 module? I think it has to do with the pin out pointing to the SD card and not the on-board eMMC flash.
I found a few threads here stating that you can alter the board physically to get it to work but that's a pain."

The eMMC that would be on-board a non-lite CM3 uses the same "pins" that the SD card would use.  So, it's an either/or sort of thing.  You can't have a SD card inserted when using eMMC.  

Yes, there is a list of super tiny resistors that you can move on the Compute Module 3 itself that can cause it to disable its onboard eMMC and act like a Lite.  We have successfully tested this, but I would not recommend it to anyone.  

So, your two options for using a non-lite is to move around the resistors (which we definitely do NOT recommend) or doing like you did and then never use the SD slot.

Our recommendation is to still use the CM3 Lite or CM3+ Lite, but I do understand that they are hard to purchase at the moment.

[almighty_malgus]

Nice writeup, almighty_malgus! 

I have a question about this step.
"- Once those are installed plugin your Freeplay board with the CM3 slotted to your Windows Machine"

Did you use something like a "USB A to A" cable to plug into a USB-A port on your computer or did you plug in to a USB-C port on your computer using a "USB C to A" cable?

Now, for your question.

"Why does the CM3 board only use the lite versions of the CM3 module? I think it has to do with the pin out pointing to the SD card and not the on-board eMMC flash.
I found a few threads here stating that you can alter the board physically to get it to work but that's a pain."

The eMMC that would be on-board a non-lite CM3 uses the same "pins" that the SD card would use.  So, it's an either/or sort of thing.  You can't have a SD card inserted when using eMMC.  

Yes, there is a list of super tiny resistors that you can move on the Compute Module 3 itself that can cause it to disable its onboard eMMC and act like a Lite.  We have successfully tested this, but I would not recommend it to anyone.  

So, your two options for using a non-lite is to move around the resistors (which we definitely do NOT recommend) or doing like you did and then never use the SD slot.

Our recommendation is to still use the CM3 Lite or CM3+ Lite, but I do understand that they are hard to purchase at the moment.

I used USB A to USB A.
Thanks for your reply!