My Firefly RK3288 is dead.

adamo.a60

ganggangstyle-e Posted at 3/6/2015 15:23
for my experience.
    1.in the mask mode is press reset button and quick press recovery button and ...

Dear all,
Many thanks for your suggestions, and excuse me for my delay answering. Me and a friend of mine we have been engaged to get operating the dac hardware that is the basis of our project. We worked on the kernel 3:19 and we had to correct many settings, incorrect or inappropriate, that we found inside the Firefly basic kernel 3:10. We added also the driver for our hardware.
Now everything works fine, but booting on an SD card generated with a perfectly working Firefly card. The entering the "mask-rom mode", even after the execution of the procedure suggested by busybee in its post dated 3/5/2015 17:01:50, is no possible. We, still now, cannot write into the eMMC, nor into the SD card. It seems the otg is out of order, but I have not tools for testing it.
Any suggestion?

adamo.angelo

busybee Posted at 3/5/2015 17:01
The last resort is to force the board into maskrom mode.

Please have a careful look at the bottom ...

Hi busybee.

I tried several times the procedure you describe here, but nothing happens; no output on RS232, no devices recognized by the 'rkflaskit' utility. Maybe, the program that has to be running while the card is in maskrom mode is some other that I don't know.
Can you help me going out from this situation?
Thank you
Angelo Adamo

busybee

adamo.angelo Posted at 3/20/2015 23:29
Hi busybee.

I tried several times the procedure you describe here, but nothing happens; no outp ...

There's no serial output when entering maskrom.
Also, rkflashkit might not support maskrom mode.

Please run:
   sudo lsusb
to see if the device will be correctly detected first.

Then use rk's upgrade_tool in Linux or AndroidTool in Windows to proceed.


If the USB OTG port is broken, then the maskrom method does not work.
You've to resort to SD card boot. Does the SD card boot also fail?

If SD card boot also fails, check the hardware voltage described at the post:
http://developer.t-firefly.com/e ... =224&extra=page%3D1

adamo.angelo

The problem is this: the OTG is not recognized: lsusb with cable connected and with no cable connected is the same.
upgrade_tool says:
List of rockusb connected
No found rockusb,Rescan press <R>,Quit press <Q>:

The strange thing is that I flashed the Ian Morrison ubuntu 14.04 image into an sd-card and this works perfectly. Using dd command I made an image of the eMMC of a good Firefly board and, through the sd-card, I copied back to the eMMC of the broken board. And this work perfectly!
The only thing I cannot do is enter the maskrom mode, and this is necessary if you want to play with firmware and kernels.
It seems that the OTG is broken: is there any tool to test it?

Really, I need to enter the loadmode to be able to flash firmware and kernels, but this is not possible, due to something missing in the low level firmware of the board or because the OTG port is broken.

busybee

adamo.angelo Posted at 3/23/2015 16:58
The problem is this: the OTG is not recognized: lsusb with cable connected and with no cable connect ...

Obviously, the OTG is broken.
Please check the connectivity using a multimeter.
It's very likely the OTG dock isn't sold well, or not well connected with the usb cable.

It's OK to flash the kernel partition by the Linux dd command. But this is not convenient.

adamo.angelo

Dear busybee,

If OTG cable is in, the voltages I read on the board at OTG pins are:
    1.     +5.09Vcc
    2.     +0.02Vdc
    3.     +0.30Vdc
    4.     +2.27Vdc
    5.      0Vdc

It seems ok, from the hw point of view! Or not?
What can be the problem?

busybee

Since the  system is recovered, we suggest you  do some test to the USB OTG in  Android system to see if the OTG is really broken.

You can plug a usb mouse/keyboard/harddisk to the otg port via an otg adapter.

1. If the mouse/keyboard/harddisk works, then otg function is considered good.
   You can check the RECOVERY and RESET button.

2. If the devices do not work, check the voltage drop of the OTG DM to GND, and OTG DP to GND.
(Use the diode function check of the multimeter). Post the result here.

adamo.angelo

OTG doesn't work. I connect a pendrive through an adapter cable, but it is not recognized, while in the perfect working card it is promptly mounted as /dev/sda1.

The voltages I read on the OTG pins  are those I wrote in the previous message:

    1.     +5.09Vcc
    2.     +0.02Vdc
    3.     +0.30Vdc
    4.     +2.27Vdc
    5.      0Vdc

I have to investigate the reason why the OTG port doesn't work...

busybee

adamo.angelo Posted at 3/27/2015 01:56
OTG doesn't work. I connect a pendrive through an adapter cable, but it is not recognized, while in  ...

Not voltage, but voltage drop.

2. If the devices do not work, check the voltage drop of the OTG DM to GND, and OTG DP to GND.
(Use the diode function check of the multimeter). Post the result here.

adamo.angelo

busybee Posted at 3/27/2015 09:16
Not voltage, but voltage drop.

2. If the devices do not work, check the voltage drop of the OTG ...

I think I understood what the problem the otg port has: pin OTG_DP is always at 0V.
If I measure the resistance DP to GND and DM to GND while the power is off, I see 2,5Ohm for the first and hundreds of kilohms for the second. Since I followed on the schematic drawing the OTG_DP wire from pin3 of the OTG plug to CPU pin and no circuit is implied in between other than the CPU pin B26, I guess, either a short circuit on the board, or the CPU pin B26-OTG_DP is broken, showing a low resistance value to GND. If the second is the case, I ask Firefly why, although the schematic drawing does include several protection circuits against electrostatic currents, they haven't been mounted on the PCB: probably, a voltage spike would have been absorbed by those circuits and would not have damaged the sensitive pins of the CPU.

Any suggestions other than send back the card to Firefly for repair?