Thread: No pre-boot mode possible on DriveSmart 50 LMT-D 5 ?

You clearly could access preboot previously because you loaded RGN fw as per this post elsewhere:

Hi, Butters, I have a Garmin DriveSmart 50 LM, which I rewrote the firmware with a Dezl 580, but when I restarted it, the screen was inactive. When I returned to the DriveSmart 50, it was working properly again. Then, using the rgn Dezl 580 file, I created a Cure3 rgn file, which I installed using Updater, hoping that I could somehow to recalibrate the screen. Now I can't go back to DriveSmart 50 because it doesn't enter in preboot mode at all. I formatted the device with RMPrepUSB but in vain, then I formatted it with Windows, also in vain. It always appears on the screen that it is connected to the PC. What can I do?

It seems likely that when you've tried to change from DS to dezl and vice versa there has been some corruption or incompatibility of firmware. So i need to know exactly what you did, in detail, step-by-step using a time-line for the conversion/re-conversion and what firmwares you used with links to those firmware files please (also state if the fw was original or hybrid, also the HWIDs used in the RGN files if overwritten in RGN_Tool). Also state if you have hard-reset and/or cleared nonvol and whether you've kept any copy/s of the nonvol region at any point in the manipulations.

To help you we have to establish precisely the chain of events as well as what is the firmware loaded presently and whether HWIDs were changed along the chain. With that precise knowledge the device might be recoverable.

The truth is that I never managed to enter preboot mode with this device, with the classic method, neither with DS firmware, nor with dezl firmware. I've done it many times with other devices, but not with this one. It enters the preboot mode, when I put a card in it that contained Garmin\Updater\2826\ or Garmin\Updater\2267\ and the files 0E.bin, 7F.bin, 9E.bin, Ldr.bin, update.txt, as appropriate, depending on the installed firmware (dezl or DS). When I inserted the card, 'loading' appeared on the screen and it remained locked at this point. Then when I restarted it, 'System software missing' appeared on the screen and in this way it automatically enters preboot mode. This way, using Updater, I install one firmware or the other. I've done this several times. When it had DS firmware all was OK, when it had dezl firmware, the touch screen was completely inactive. I tried to recalibrate the screen, but failed to enter 'screen calibration' mode. Then, with the firmware dezl, in the device, I inserted a card again with the files described above and after 'System software missing' appeared on the screen I used Updater with the Cure3 file I wrote about earlier.

So you now have a cure firmware ramloader loaded, but which fw is it? The dezl 580 HWID 2826 with it's own boot.bin/Ldr.bin, or 'hybrid firmware' with HWID 2267 DS50's boot.bin/Ldr.bin? Please also advise whether you have any backup of nonvol and if so when made (with which fw loaded).

Please also give a link to dezl 580's firmware version used, it's essential you supply it.

So the last fw flashed to it was the dezl 580 cure and it now has HWID of 2826. With cure fw loaded it should have Mass Storage Mode enabled but be stuck on the Garmin splash screen, it that what you're seeing?

It would also have the dezl bootloader in region 5 and it's x-loader in region 43 if it's completed a boot cycle or even partially booted after the dezl's ramloader was flashed to region 12.

This is entirely at your risk to attempt: I would flash the DS fw back to it via its individual BIN files on SD... but initially using the dezl ramloader (as Ldr.bin, first overwritten to HWID 2267). i.e. Garmin\Updater\2826\update.txt. If you aren't sure what to do and want me to make a flash kit let me know. Provided you then have HWID 2267 and a working DS you can flash full original DS fw to it so it has correct regions 5 & 43.

You should clear nonvol after each successful flash. This device will have had some potentially damaging/confused data in region 154 after the constant flashing/re-flashing it's experienced and it may even unexpectedly hard-brick. Region 5 is a particularly risky region, if it gets corrupt the device will die and never boot again.

PS: Where did you source V4.00 dezl 580 firmware? Is it really V3.90 renamed?

I don't think I understood very well what needs to be done. I am sending you some more files: Garmin DS 50.jpg - this appears on the screen, RMPrepUSB.jpg - this appears in RMPrepUSB, GUPDATE.GCD (DS 50) - before making any changes and GUPDATE.GCD (dezl) - created after change. I tried to restore the firmware with WebUpdater, but this only creates the GUPDATE.GCD file. Version 4.00 also appears in the GarminDevice.xml file that I sent you, which the device created when it had normal dezl firmware, not the current one. [Only registered and activated users can see links. ]