Flash problems to ESP8266 boards

By Atomstar on Thursday 21 November 2019 21:32 - Comments (1)
Category: ESP8266, Views: 1.558

Note to self: sometimes I cannot write to ESP8266 boards. The solution appeared to be to disconnect serial devices first (e.g. MH-Z19B), then flash

Symptoms

  • Typically freshly bought boards (Wemos D1 mini Pro) running micropython
  • esptool.py reports: A fatal error occurred: Failed to connect to Espressif device: Timed out waiting for packet header
  • Arduino reports: error: espcomm_open failed error: espcomm_upload_mem failed
  • Cannot interact or write to Micropython REPL prompt, commands are not fed back (i.e. I only have RX no TX capability)

Diagnosing ESP8266 boards

To see what the board is doing, connect to USB, then run screen on the tty:
screen /dev/tty.usbserial-1420 {74880,115200}

Or use Arduino 'Serial logger'. Use baud 74880 for boot loader, 115200 for programs running on the board (in my case). This gave me:

21:32:09.624 -> OSError: [Errno 2] ENOENT
21:32:09.624 -> 
21:32:09.624 -> MicroPython v1.9.4-8-ga9a3caad0 on 2018-05-11; ESP module with ESP8266
21:32:09.624 -> Type "help()" for more information.
21:32:09.624 -> >>> 


Once I found the board was running Micropython (i.e. ruling out HW problem), I found that I could connect but not write to the Micropython prompt.

Solution

In my case the problem appeared to be that a sensor using the serial port blocked my input to the serial port for uploading. Disconnecting the sensor worked. HTH.

Infrared remote control hell with an Intel NUC, Logitech Harmony, lirc, ir-keymap and Kodi

By Atomstar on Monday 11 November 2019 09:00 - Comments (3)
Categories: HTPC, Linux, Views: 1.677

So I got a new (second hand) Harmony Remote and would like to control my AV setup with this. I document my findings in the jungle of IR control on Linux here.
  1. Old situation: Kodi (on Intel NUC/Ubuntu 18.04) controlled via LIRC using Apple TV remote
  2. Desired situation: Samsung TV + Pioneer AV receiver + Kodi on NUC controlled with Logitech Harmony and Kodi also with the Apple TV remote.
What's working:
  • Harmony remote controls all devices
  • AppleTV and Harmony can both navigate Kodi
  • Harmony shuts down Kodi and NUC
What's not working:
  • Kodi doesn't detect all keys from Apple TV remote (e.g. KEY_OK / KEY_MENU / KEY_BACKSPACE). Workaround: use KEY_DELETE and remap in Kodi's keyboard.xml
What's unclear:
  • Why does evtest show two IR event inputs?
  • Why does Kodi have multiple keymaps?


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