I’ve bought this little device ESP32 C3 desktop trinket Mini TV Portable Pendant LVGL 1.44inch LCD ST7735 Brand Spotpear
It has a 128x128 screen and 4 buttons (reset+3). It can be used as a multi-button command that displays status messages.
I did not find reliable instructions to setup the device using Arduino IDE so I’ve decided to go the tasmota route. So here is what I’ve done:
-
Flash the device with tasmota using `ESP-Flasher`
and a suitable firmware.This repositorycontains several unnofficial fw’s, I’ve used `tasmota32c3-lvgl.bin` -
When tasmota boots for the first time it asks the wi-fi credentials. Tasmota will then reboot and the device will display a blank screen
-
It’s now necessary to define the GPIO pins. For this device I had to compare the diagram posted by the vendor with tasmota requirements, resulting in.
-
Now MQTT needs to be parametrized so that openHAB (or other app) can use the device. I also used the `SO73 1` command so that buttons can be identified. Tasmota will now reboot. The console should display a successfull login to your mosquitto broker. You need to define a topic for the device (in my case display-secador)
-
Using Tools → Manage File System you have to upload the following 3 files to the device
display.ini (this is not app dependent, you can use it as is)
:H,ST7735,128,128,16,SPI,1,*,*,*,*,*,*,*,40
:S,2,1,1,0,40,20
:I
EF,3,03,80,02
CF,3,00,C1,30
ED,4,64,03,12,81
E8,3,85,00,78
CB,5,39,2C,00,34,02
F7,1,20
EA,2,00,00
C0,1,23
C1,1,10
C5,2,3e,28
C7,1,86
36,1,48
37,1,00
3A,1,55
B1,2,00,18
B4,1,04
B6,3,08,82,27
F2,1,00
26,1,01
E0,0F,0F,31,2B,0C,0E,08,4E,F1,37,07,10,03,0E,09,00
E1,0F,00,0E,14,03,11,07,31,C1,48,08,0F,0C,31,36,0F
11,80
29,80
:o,28
:O,29
:A,2A,2B,2C,16
:R,36
:0,C0,00,00,00
:1,A0,00,00,01
:2,00,00,00,02
:3,60,00,00,03
:i,20,21
autoexec.be (this defines how the device will interpret commands sent via mqtt)
import haspmota
import string
haspmota.start()
tasmota.add_cmd('msgs',
def (cmd, idx, payload, raw)
global.p1b20.text = string.format("%s",raw["msg1"])
tasmota.resp_cmnd_done()
end)
Basically this says that when the device receives a cmnd/display-secador/msgs with payload {“msg1”:”any text”} the variable p1b20 (id20 on page 1, see file below) gets its value modified by “any text”. It’s possible to define more fields, but in this case pls use a smaller font, the device has a small screen and there is no much space available for characters.
pages.jsonl (this file defines the screen layout for my application)
{"page":0,"comment":"---------- Upper stat line ----------"}
{"id":11,"obj":"label","x":0,"y":0,"w":100,"pad_right":5,"h":22,"bg_color":"#D00000","bg_opa":255,"text_color":"#ffffff","radius":0,"border_side":0,"text":"","text_font":"montserrat-20"}
{"id":12,"obj":"label","x":101,"y":0,"w":27,"pad_right":5,"h":22,"bg_color":"#00ff00","bg_opa":255,"text_color":"#ffffff","radius":0,"border_side":0,"text":"","text_font":"montserrat-20"}
{"id":13,"obj":"label","x":101,"y":105,"w":27,"pad_right":5,"h":22,"bg_color":"#0000ff","bg_opa":255,"text_color":"#ffffff","radius":0,"border_side":0,"text":"","text_font":"montserrat-20"}
{"id":15,"obj":"lv_wifi_arcs","x":2,"y":0,"w":29,"h":22,"radius":0,"border_side":0,"bg_color":"#000000","line_color":"#FFFFFF"}
{"id":16,"obj":"lv_clock","x":30,"y":3,"w":55,"h":16,"radius":0,"border_side":0,"text_color":"#ffffff"}
{"page":1,"comment":"---------- Page 1 ----------"}
{"id":0,"bg_color":"#0000A0","bg_grad_color":"#000000","bg_grad_dir":1,"text_color":"#FFFFFF"}
{"id":20,"obj":"label","x":10,"y":55,"w":100,"text":"OFF","align":1,"text_font":"montserrat-28"}
Reboot the device and it will display:
I’ve used green and red colors to mark the buttons that I want to use in my app.
Finally you have to create a thing in openHAB. My definitions are:
UID: mqtt:topic:aveiro:0d8e4cd82c
label: Comando Secador de Roupa
thingTypeUID: mqtt:topic
configuration:
payloadNotAvailable: Offline
availabilityTopic: tele/display-secador/LWT
payloadAvailable: Online
bridgeUID: mqtt:broker:aveiro
channels:
- id: switch
channelTypeUID: mqtt:switch
label: Switch
configuration:
commandTopic: cmnd/display-secador/POWER
stateTopic: stat/display-secador/POWER
- id: WebServer
channelTypeUID: mqtt:switch
label: WebServer
configuration:
commandTopic: cmnd/display-secador/WebServer
off: "0"
on: "2"
- id: fw
channelTypeUID: mqtt:string
label: Firmware
configuration:
stateTopic: stat/display-secador/STATUS2
transformationPattern:
- REGEX:(.*StatusFWR.*)∩JSONPATH:$.StatusFWR.Version
- id: rssi
channelTypeUID: mqtt:number
label: RSSI
configuration:
stateTopic: tele/display-secador/STATE
transformationPattern:
- REGEX:(.*RSSI.*)∩JSONPATH:$.Wifi.RSSI
- id: status
channelTypeUID: mqtt:string
label: Status
configuration:
formatBeforePublish: '{"msg1":"%s"}'
commandTopic: cmnd/display-secador/msgs
- id: button1
channelTypeUID: mqtt:string
label: Button 1
configuration:
stateTopic: stat/display-secador/RESULT
transformationPattern:
- REGEX:(.*Button1.*)∩JSONPATH:$.Button2.Action
- id: button2
channelTypeUID: mqtt:string
label: Button 2
configuration:
stateTopic: stat/display-secador/RESULT
transformationPattern:
- REGEX:(.*Button2.*)∩JSONPATH:$.Button2.Action
- id: button3
channelTypeUID: mqtt:string
label: Button 3
configuration:
stateTopic: stat/display-secador/RESULT
transformationPattern:
- REGEX:(.*Button3.*)∩JSONPATH:$.Button3.Action
You can link items to the channels, these are the device specific ones:
- button1/2/3 - when such buttons are pressed in the device you will receive SINGLE DOUBLE TRIPLE QUAD PENTA HOLD or CLEAR. This requires that `SO73 1` has been used in device’s console. In my case I’ve only used buttons 2 and 3
- status - a short message (up to +/-10 characters with the font used in this example)
- switch - to turn the screen ON/OFF
Enjoy
super cool!