05-17-2021, 06:44 PM | #1 |
Wizard
Posts: 2,319
Karma: 9999999
Join Date: Feb 2012
Device: Nook NST, Glow2, 3, 4, '21, Kobo Aura2, Poke3, Poke5
|
Qualcomm EDL mode for Pokes, Max3
Poke 2 & 3, Max 3 use Qualcomm processors which have (like all Qualcomm) "Emergency Download Mode", EDL.
This is a ROM-based bootloader which does not require anything in flash to run. If you screw things up really bad your device may go to EDL by itself. If things are working fine you could go "adb reboot edl" or in a shell "reboot edl". If things are halfway screwed up you may not be able to reach EDL programatically. That is why many Qualcomm devices put in special test points on the circuit board to force it into EDL mode. You short these test points together while you are doing a power button reset. Ok, most people will never have anything to do with EDL mode. You also will need special software to talk EDL also: https://github.com/bkerler/edl But what if you're the type that always gets into trouble and you hate opening the back of your device all the time? Well, I put a little magnetic reed switch across the test points so that I won't have to open my device (Poke 3) ever. It's specifically insensitive so that the magnetic book cover can't activate it. You need to place a big magnet on the back of the cover and press the power button. As a special offer and if you really think you will use this, PM me and I'll drop a reed switch in the mail for you. I really can't imagine this applies to too many people; I only have a couple. The white connector? Oh, that's the console UART. It runs on 1.8V logic level, 115200-8-n-1 You'll need a level converter probably. |
05-20-2021, 09:54 PM | #2 |
Zealot
Posts: 122
Karma: 43580
Join Date: Apr 2016
Device: KPW3, Kobo Clara HD, Onyx Boox Nova 2
|
Out of curiosity, why do you short test points instead of using EDL cable (deep flash cable)? The advantages is that you don't have to open up device and it's easy to make/cheap to buy. I tested it and it works with Nova 2
|
05-21-2021, 10:07 AM | #3 |
Wizard
Posts: 2,319
Karma: 9999999
Join Date: Feb 2012
Device: Nook NST, Glow2, 3, 4, '21, Kobo Aura2, Poke3, Poke5
|
A good question.
I tried using D+ shorted to ground with a usb A socket. It didn't seem to work. That doesn't rule out that I screwed up and it could work. OTOH, the Poke3 has multiplexors for switching analog audio onto the D+/D− Maybe that affects the EDL detection. |
06-22-2021, 12:17 PM | #4 |
Wizard
Posts: 2,319
Karma: 9999999
Join Date: Feb 2012
Device: Nook NST, Glow2, 3, 4, '21, Kobo Aura2, Poke3, Poke5
|
If you end up doing this (or something similar) you might be interested in being able to test it from the command line:
Code:
# cd /sys/class/gpio # echo 57 > export # cat gpio57/value 0 # cat gpio57/value 1 # echo 57 > unexport gpio57 is correct for Poke3, no guarantee for anything else. |
04-08-2022, 12:06 PM | #5 |
Wizard
Posts: 2,319
Karma: 9999999
Join Date: Feb 2012
Device: Nook NST, Glow2, 3, 4, '21, Kobo Aura2, Poke3, Poke5
|
Just a little update. I have a Windows version of an EDL utility that's small, reliable and doesn't have any dependencies. You may prefer it to other solutions. See the website in my sig.
|
Tags |
max 3, poke 2, poke 3 |
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Is the Max3 monitor mode improved over Max2? | newnu | Onyx Boox | 4 | 09-26-2019 07:47 PM |
Qualcomm to Buy NXP | fgdas | News | 12 | 11-01-2016 09:30 AM |
Qualcomm abandons Mirasol eReader (for now) | Daithi | News | 4 | 06-02-2011 06:29 PM |
Amazon Kindle advertisment pokes fun at Apple iPad | joblack | News | 4 | 09-15-2010 02:07 PM |
Qualcomm Smartbooks this fall | mobelby | News | 4 | 05-30-2009 11:16 PM |