Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

New users please post here first and let us know a little bit about yourself.
K9JPT
Posts: 35
Joined: Fri Apr 24, 2020 10:11 am

Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by K9JPT » Fri Apr 24, 2020 10:28 am

Hams!

I recently received a Radioddity GD-77 and had numerous people tell me how pleased they are with the OPENGD77 firmware that I thought I too would like to try.

Except for the CPS appearing to install correctly the rest of the firmware install was extremely problematic. Although the HT was set in 'firmware mode' (EG: pressing two buttons under PTT) I kept receiving an error message that I needed to turn it on in order to upgrade the firmware! Baffling!

I then decided to upgrade the firmware that Radioddity offers choosing the latest version. The process appeared to go accordingly. However, I can no longer talk over DMR via my hotspot although I can hit a local analog repeater and hear over it.

I then attempted to re flash the firmware at which point I discovered the firmware mode was no longer accessible.

My issue is exactly documented in this forum at:

https://opengd77.com/viewtopic.php?f=7&t=739

However, I do not have the resources to open my HT or buy Jlinks.

Could there possibly be another route for me to try?

Thank you and 73,

K9JPT

VK3KYY
Posts: 2668
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia
Contact:

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by VK3KYY » Fri Apr 24, 2020 11:14 am

Jlink cost $15 on eBay.com as far as I can see.

If you can't afford $15, you'll need to borrow a JLink from someone locally who has one.

There is no other way to fix this, because the problem is fundamentally the really really bad design in the official bootloader.

If you can beg, borrow or buy a JLink, the fix is relatively simple and only requires the temporary soldering of 4 wires to the PCB of the radio.

K9JPT
Posts: 35
Joined: Fri Apr 24, 2020 10:11 am

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by K9JPT » Fri Apr 24, 2020 11:22 am

1. What is the model of jlink that is needed exactly.
2. I have high doubts it is as easy as you say. If memory serves me I believe I remember something you stated in another post regarding registers and resetting them or something. Additionally, there is no straight forward documentation I found that outlines this process steb-by-step. I think I might be buying stuff just to entertain others while getting deeper and deeper into the patty pie.

VK3KYY
Posts: 2668
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia
Contact:

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by VK3KYY » Fri Apr 24, 2020 12:09 pm

Its probably best if you PM EB3EEL

https://opengd77.com/ucp.php?i=pm&mode=compose&u=586

And ask them what problems they encountered.

I made it easy for EB3EEL to fix it by patching the bootloader to remove the problem of it looking for the copy protection data

In the thread, see my post

https://opengd77.com/viewtopic.php?f=7& ... t=30#p6830

Which links to

https://github.com/rogerclarkmelbourne/ ... ootloaders

K9JPT
Posts: 35
Joined: Fri Apr 24, 2020 10:11 am

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by K9JPT » Sat Apr 25, 2020 1:25 pm

Dear Roger Clark,

Thank you for the links and details you provided. I placed an order last night for the:

https://www.banggood.com/USB-ARM-STM32- ... rehouse=CN

and wanted to ask what other materials I may need?

For example: Do I need to purchase special wires separately that will fit into the GPIO header? I also noted that you spoke about a Bench PSU. If I do not have one what is the next best thing I can do? My personal opinion is that it's better to buy a new radio if is gonna require the purchase of $100 items just to repair. That would make better economical sense to me. I don't follow any rule of throwing money in the wind just because I may have it.

I apologize to everyone for talking about money in this post. Lately, I have heard over the air many amateurs speak about how they will spend their stimulus check on a new radio while their next door neighbor who is a waitress is laid off from work with two kids trying to make ends meet. Two very different needs.

Many enthusiasts enjoy this safe space as it gives comfort from the hassles and threats of current living. Certain issues you many be trying to escape should be left behind the door. Today in many countries people are struggling to make car payments, insurance payments, pay for utilities like oil, telephone, electric and internet, mortgage, food, school, petrol etc... etc... and life is hard for many. Americans are especially at risk because many were given government checks from the U.S. government to help assist in some way. But that doesn't mean we are all millionaires. We were only fortunate that our country entered this unwanted situation in a position of strength and not weakness.

I look forward to fixing my GD77 radio with the help of the community and advocating the spirit yours positively reflects.

73

K9JPT

VK3KYY
Posts: 2668
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia
Contact:

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by VK3KYY » Sun Apr 26, 2020 12:24 am

I'm a bit concerned that link says STM32 on it, because the radio does not use the STM32 chip.

There are a couple of options.

Get a unknown JLink e.g. from Amazon

https://www.amazon.com/J-Link-Debugger- ... 789&sr=8-3

And if it doesn't work, get your money back

Or buy an official J-Link Edu

https://www.amazon.com/Segger-J-Link-ED ... 567&sr=8-1

Which is an official product but can't be used or commercial work.

I do have a J-link Edu, but I've never had time to actually try it

K9JPT
Posts: 35
Joined: Fri Apr 24, 2020 10:11 am

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by K9JPT » Sun Apr 26, 2020 1:26 am

Thank you for the concern and recommendations! Very much appreciated! I looked at the Amazon link you sent and within the product description it is stated:

J-Link V8 Debugger JLINK Arm Cortex-M4/M0 Emulator Downloader USB Charge

The product description from the product I ordered states:

* Support ARM7/9/11 (including thumb mode), Cortex-M0/M1/M3/M4 core

Additionally, within the FAQ segment of the description I sent you of the product I orderd the following Q&A took place:

Q:
Does this work with Atollic(Truestudio) stm32?, Atollic want to reprogram it, and shows the programming bar, but then says cannot connnect? Connecting to J-Link... Connecting to J-Link failed. Connected correctly? GDBServer will be closed... Shutting down... Could not connect to J-Link. Please check power, connection and settings. What is the settings to be used?

A :
Jlink V8 Debugger ARM ARM7 Emulator,this work with Jlink .
Answered by wujiahui on November 03,2019 Helpful

Does any of this help confirm that I have or don't have the correct product ordered?

Thank you and 73!

K9JPT

VK3KYY
Posts: 2668
Joined: Sat Nov 16, 2019 3:25 am
Location: Melbourne, Australia
Contact:

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by VK3KYY » Sun Apr 26, 2020 1:33 am

Atollic(Truestudio) stm32?
Is a completely different development system for a different processor.
All the radios that are currently supported use the NXP MK22 processor

So that Q/A is irrelevant

I think if you by the $16 "J-Link V8 Debugger JLINK Arm Cortex-M4/M0 Emulator" its likely to work.
I have several similar looking devices, and they all work OK for me

EB3EEL
Posts: 37
Joined: Wed Mar 11, 2020 6:35 am

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by EB3EEL » Sun Apr 26, 2020 1:44 am

Hello, i think that the $16 jlink you buy is good, the processor on the gd77 if i remember well is a cortex m4, the only you need is four wires to connect and be careful with the position on wires, start the program, run and voila !!, the magic is done and your radio is come alive.
If you follow the instructions on the post that Roger say before, no problem, and if you have any question here we are.
In this moment cant upload some photos of the wiring and connections, when I found it I post in a next reply, but is easy if you have a little experience in open and work with electronics.
As I see in the amazon link is the same jlink I have and works well, be optimist and in a few days you have a superb radio with the opengd software that is very good.
Last edited by EB3EEL on Sun Apr 26, 2020 2:01 am, edited 2 times in total.
Miquel EB3EEL 2143638 Barcelona, Catalunya, Spain

K9JPT
Posts: 35
Joined: Fri Apr 24, 2020 10:11 am

Re: Wanting to use OPEN GD77 BRICKED My HT and broke 'bootloader mode' :(

Post by K9JPT » Sun Apr 26, 2020 1:54 am

Unless I'm missing something that I don't understand both of the product descriptions you sent to me state they support:

J-Link V8 Debugger JLINK Arm Cortex-M4/M0 Emulator

The product I bought also states:

Support ARM7/9/11 (including thumb mode), Cortex-M0/M1/M3/M4 core

None of the three talk about the NXP MK22 processor.

But the similarties amongst all three appears to be support for the ARM7/9/11 (including thumb mode), Cortex-M0/M1/M3/M4 core

So what am I failing to understand?

Post Reply