Flashing firmware - sw_reset loop?

Support
1

I am attempting to flash my first TTGO LORA32 v1.0 915mhz device using esphome-flasher and running into trouble. I am using esphome-flasher because the meshtastic web installer gives me a “failed to initialize” error. I have downloaded all the suggested drivers and do see the device show up in device manager on a COM port.

I purchased 2 of the devices on aliexpress at the following link.

https://www.aliexpress.us/item/2251832810444969.html?spm=a2g0o.order_list.order_list_main.5.63b31802JOVmL8&gatewayAdapt=glo2usa&_randl_shipto=US

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image11169×1156 234 KB

I have downloaded the firmware zip files from github, unzipped them on my drive, and have attempted flashing the 2.1.2, 2.1.1, and 2.1.0 revisions. In all cases, when I attempt to flash the standard .bin file, I get following error:
Unexpected error: The firmware binary is invalid (magic byte=55, should be E9)

I read on the forum that the update.bin file may correct the issue. I am able to successfully flash the update.bin file, but immediately upon completion, it appears to go into a reboot loop that obviously continues as long as I leave the device powered on.

The specific files I’ve attempted are below:
firmware-tlora-v1-2.1.2.6d20215.bin (firmware binary invalid error received)
firmware-tlora-v1-2.1.2.6d20215-update.bin (reset loop received)
firmware-tlora-v1-2.1.1.dc2ca9c.bin (firmware binary invalid error received)
firmware-tlora-v1-2.1.1.dc2ca9c-update.bin (reset loop received)
firmware-tlora-v1-2.1.0.331a1af.bin (firmware binary invalid error received)
firmware-tlora-v1-2.1.0.331a1af-update.bin (reset loop received)

I tried to erase as well with the following file:
Meshtastic_nRF52_factory_erase.uf2 (firmware binary invalid error received)

Flash log showing reboot loop:
Using ‘COM9’ as serial port.
Writing at 0x001eb344… (100 %)Wrote 1963408 bytes (1207460 compressed) at 0x00010000 in 27.3 seconds (effective 576.3 kbit/s)…
Hash of data verified.

Leaving…
Hard Resetting…
Hard resetting via RTS pin…
Done! Flashing is complete!

Showing logs:
[20:12:43]ets Jul 29 2019 12:21:46
[20:12:43]
[20:12:43]rst:0x3 (SW_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
[20:12:43]configsip: 0, SPIWP:0xee
[20:12:43]clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
[20:12:43]mode:DIO, clock div:2
[20:12:43]load:0x3fff0018,len:4
[20:12:43]load:0x3fff001c,len:1044
[20:12:43]load:0x40078000,len:8896
[20:12:43]load:0x40080400,len:5828
[20:12:43]entry 0x400806ac
[20:12:43]ets Jul 29 2019 12:21:46
[20:12:43]
[20:12:43]rst:0x3 (SW_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
[20:12:43]configsip: 0, SPIWP:0xee
[20:12:43]clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
[20:12:43]mode:DIO, clock div:2
[20:12:43]load:0x3fff0018,len:4
[20:12:43]load:0x3fff001c,len:1044
[20:12:43]load:0x40078000,len:8896
[20:12:43]load:0x40080400,len:5828
[20:12:43]entry 0x400806ac
[20:12:44]ets Jul 29 2019 12:21:46
[20:12:44]
[20:12:44]rst:0x3 (SW_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
[20:12:44]configsip: 0, SPIWP:0xee
[20:12:44]clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
[20:12:44]mode:DIO, clock div:2
[20:12:44]load:0x3fff0018,len:4
[20:12:44]load:0x3fff001c,len:1044
[20:12:44]load:0x40078000,len:8896
[20:12:44]load:0x40080400,len:5828
[20:12:44]entry 0x400806ac
[20:12:45]ets Jul 29 2019 12:21:46
[20:12:45]
[20:12:45]rst:0x3 (SW_RESET),boot:0x17 (SPI_FAST_FLASH_BOOT)
[20:12:45]configsip: 0, SPIWP:0xee
[20:12:45]clk_drv:0x00,q_drv:0x00,d_drv:0x00,cs0_drv:0x00,hd_drv:0x00,wp_drv:0x00
[20:12:45]mode:DIO, clock div:2
[20:12:45]load:0x3fff0018,len:4
[20:12:45]load:0x3fff001c,len:1044
[20:12:45]load:0x40078000,len:8896
[20:12:45]load:0x40080400,len:5828
[20:12:45]entry 0x400806ac
[20:12:46]ets Jul 29 2019 12:21:46

2

Please use one of the supported flashing methods, esphome is not supported.

3

Not sure… But I think you have to put the device into ‘flash’ or ‘bootloader’ mode by grounding out GPIO 0 before powering up. I haven’t done it thisway, but I’ve read it in a few places. Hope this gives you a clue.

Good luck.

4

Where is this information from?

5
6

Like I said… I haven’t tried this. I used to use ESPHOME Flasher and kept getting errors. I now use the web flasher.

Just thought the shorting of GPIO 0 could solve your problem.

7

I did attempt the Meshtastic web installer (https://flasher.meshtastic.org/) and received the stated error. In an act of desperation, I attempted the oldest revision available in the web installer and it worked. It appears there is something specific to the newer releases and the TTGO LORA32 V1 that prevents the firmware from loading. At this time I have successfully flashed V2.0.0.18ab874 beta.