Modify RM520NGLAP to have USB

Hello there,
I have acquired a RM520N-GLAP that has been modified to run AA firmware and USB works. I am trying to replicate the same thing on a non-modified AP variant. So far I discovered that you can flash AA firmware to it by entering EDL/QDLoader mode manually and editing the XML in the firehose directory to say:

c_project_name=“RM520NGLAP_VB”

Qflash says pass but I still don’t see any USB ports (nor does rc PCIe ethernet work)

I noticed on the modified one the upper right corner under the cover has been pulled up.

Anyone know how to turn a RM520GLAP into an AA?
Thanks!

I’m interested in a solution for this as well. I was able to flash AA firmware to the AP version module but no ports are available. Here is a picture of the unmodified AP module next to the modified AP module. You can see the modified AP module on the right has the top right of the case cut away for some reason. Im not sure if there is hardware reason that usb does not work on the AP variant that they are bypassing somehow and that is why they are cutting the case for whatever modification they are doing.

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don’t know if it is true, but i’ve heard something about a setting with efuse, with a special option you can’t reverse a glap to glaa, but if they need to cut a piece of shield, i’m sure the reason is there, maybe a phisycal bypass or a schematic bridge to be fixed…very interesting topic.
a glap version is sold the half price of a glaa, so i was quite sure glap has something less than a glaa, from pictures it seems not

Dear @iamromulan
Did you try to delete c_project_name=“RM520NGLAP_VB” and try?
After upgrade, did module work or not?
What is the original firmware?

Can you take a photo of just the cut shield section please?

Dear @Raoul_Ferro
Yes, for efuse module, it can’t convert to USB via AT command.

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That we know. Question is how do you convert it to USB if not via AT command.

Dear @mevgheni
If RM520MGLAP, it can’t convert to USB, it is PCIe only.

I am in possession of a modified RM520MGLAP and USB does work. I’m not sure how this was achieved, which is why I asked. :grin:

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Can you take a quality photo of the cut shield section of your modified unit?

I will try to do that later today. Unfortunately I accidentally broke a chip off the corner on both modems so keep that in mind :sweat_smile::joy:
It didn’t seem to effect functionality on the modified AP modem though.

I Marked a red arrow where I accidently removed a chip from it on both. Doesn’t seem to effect the modified one with USB working (on the left)
The one on the right so far I have entered EDL mode and flashed Arixolink firmware. It seems to be the only firmware I can flash meant for AA. I had to modify the project name as well. I need to get ahold of regular AP firmware though because it doesn’t show up in PCIe or USB.

Dear Sirs,
It is not recommanded to modify the component in module.

maybe the quality of pictures is driving me wrong, but it seems that modded one has more “hardware”(mlcc) on board…maybe that section (usb zone) is burned and need a new line, so with less mlcc who caares, the rest works good enough capped,how many maybe, but i see a scratch on m.2 pin, is it correct?

@iamromulan,

Edit: Sorry i seen where you mentioned the arrow is component you broke off. My ‘theory’ went down the tubes , I guess.

Where your arrows are wonder if this is like a jtag interface , . Whoever modded the MOD unit,made like a jig/fixture, to tempoarirly solder were your red arrow is,and rewrote efuse,then remove the burning fixture? Always wonder what happened on a deal like this.
I have a GLAP currently,not knowing there were two versions of this modem,that was dead when i puchased it. Am going to do a return,unless this setup you have would actually wrok.
Mine only shows /dev/mhi_BHI,no other ports under linux… No ports in windows.

TIA for posting your information BTW.

@Iamromulan ,

Am curious as to what would be the extra port that is created under linux if you have manually entered EDL mode? I know under Windows in device manager you should see QDLoader.
With my GLAP modem,under linux all i ever see is a /dev/mhi_BHI , nothing else. it was this way when I recived the module.
I havent tried soldering to the two pads to short at boot.
If i try and do a qfirehose it fails at:

[000.030]: Totals checking 29 files md5 value, 0 file fail!
[000.030]: find 'prog_firehose_lite.elf'
[000.030]: find_firehose_mbn prog_firehose_lite.elf
[001.032]: bhi_ee = 5
[001.032]: bhi_ee is not MHI_EE_EDL
[001.033]: usb_linux.c qpcie_open 1375 fail
[001.033]: qfirehose.c main 641 fail

Am wondering if i could get the modulke into EDL mode qfirehose may at least attempt to flash?

TIA

I just took some pics for pinout.
What pins to shorten to get into EDL ?