Karma refusing to pair - Reverse engineering investigation

[Boko]

Rev-C read the SD card for a moment.but RevEが機能しない

 

[account deleted]

Rev-C read the SD card for a moment.but RevEが機能しないView attachment 703

I have Rev C. and Rev E.
Works on both revisions.

Most likely there is poor contact, or unwashed flux after soldering.

It's hard to see in the photo, have you connected the power contacts of the SD card?

 

[account deleted]

Rev-C read the SD card for a moment.but RevEが機能しないView attachment 703

 

[Boko]

0Ωの抵抗がなかったのでジャンパーを使いました。
リボンケーブルが接続されています

 

[mefisto82]

Rev-C read the SD card for a moment.but RevEが機能しないView attachment 703

Rev.D doesn't boot from microSD.....

 

[account deleted]

Rev.D doesn't boot from microSD.....

What symptoms does this occur with?

I came across these:

1)The terminal displays an attempt to boot from NAND. - TP1 is not connected to TP2.

2) No data in the terminal emelator, but the power indicator is on - Bad contact SD, not soldered SD holder, flux has not been washed off.

3) An attempt to boot from SD is displayed, but the process does not proceed further - this could be either a problem with the image, the SD card, or the problem from point 2

 

[account deleted]

In any case, your task is to at least boot into U-boot, any revision should load it, and from it you can already read data from SD into RAM and then flash it into NAND The procedure is a little more complicated, but it should also solve the firmware problem.

Try it, it also took me more than one evening and a certain amount of additional equipment.

 

[account deleted]

If anyone managed to restore their drone, please write about it here and share your experience.

 

[mefisto82]

What symptoms does this occur with?

I came across these:

1)The terminal displays an attempt to boot from NAND. - TP1 is not connected to TP2.

2) No data in the terminal emelator, but the power indicator is on - Bad contact SD, not soldered SD holder, flux has not been washed off.

3) An attempt to boot from SD is displayed, but the process does not proceed further - this could be either a problem with the image, the SD card, or the problem from point 2

Probably 1. I soldered TP1, but probably not nice clean contact on TP2 on motherboard..... I will try tomorrow.... I was use Floppy cable to solder on motherboard MicroSD place....and to Adapter MicroSD. I checked with multimeter and no short contacts.
On your first attempt/video......yours TP1 is different? Is this TP37?

 

[Boko]

これはどのような症状で起こりますか?

私はこれらを見つけました：

1) 端末に、NAND からブートしようとしている旨のメッセージが表示されます。- TP1 は TP2 に接続されていません。

2) 端子剥離器にデータはありませんが、電源インジケータはオンです - SD の接触不良、SD ホルダーが半田付けされていない、フラックスが洗い流されていません。

3) SD から起動しようと表示されますが、プロセスはそれ以上先に進みません。これは、イメージ、SD カード、またはポイント 2 の問題のいずれかである可能性があります。

 

[Boko]

TP1 を TP2 に接続して電源ボタンを押しても、本体には何も表示されません。これは SD が挿入されているのかどうかに関係なく同じです。

一度3までいきました

 

[mefisto82]

Probably 1. I soldered TP1, but probably not nice clean contact on TP2 on motherboard..... I will try tomorrow.... I was use Floppy cable to solder on motherboard MicroSD place....and to Adapter MicroSD. I checked with multimeter and no short contacts.
On your first attempt/video......yours TP1 is different? Is this TP37?

What about this place for MicroSD?

 

[account deleted]

Probably 1. I soldered TP1, but probably not nice clean contact on TP2 on motherboard..... I will try tomorrow.... I was use Floppy cable to solder on motherboard MicroSD place....and to Adapter MicroSD. I checked with multimeter and no short contacts.
On your first attempt/video......yours TP1 is different? Is this TP37?

TP66 = TP1

 

[Boko]

Confirm that the SD card pins are connected to D3-D9, 3.3V between VDD vss, no short circuit, why is it not loading?

 

[account deleted]

TP1 を TP2 に接続して電源ボタンを押しても、本体には何も表示されません。これは SD が挿入されているのかどうかに関係なく同じです。

一度3までいきました

This is should happen, look for a problem with connecting the SD card, or writen image

 

[account deleted]

I took the first SD tray I came across and checked all the cards with the image laid out - everything works.

 

[account deleted]

At the moment, I’m temporarily stopping my experiments and starting work on the remote control, I want to understand how I can load my maps, if someone can help me and download a dump from their remote control with loaded maps, I will be grateful.

 

[Boko]

最初に見つけた SD トレイを取り出し、イメージがレイアウトされているすべてのカードを確認しました。すべて正常に動作しました。

OK?

 

[mefisto82]

OK?

In MiniPartitionWizard this image file has three partition. Two of them cannot read in Windows.

 

[dokgotak]

View attachment 704

what is the component, you soldered?