Display on st7735 sd18b20 temp on an other esp32 board?

ESPHome
1

Hello,
After some day,s trail and error guided by tutorials and video,s I finnaly ask for help.
I would like to display on a st7735 temp. Value from a sd20b18 sensor mounted on a other board.
The display is working with data on his own board like wifisignal strenght.
But the temp. Value from a other board for me not possible to achief.
So one esl32 in basement with ds20b18 sensor.
And one esp32 in my livingroom with the display.

All is working to my satisfaction apart from displaying the temperature.

Howe to aproch this to solve this problem?
By means of template? Or custom sensor?
Like to hear.
Regards Theo

2

Without any details it’s going to be hard to assist you. For instance do you use Home Assistant? If so use a suitable text sensor - either platform: homeassistant or platform: mqtt_subscribe depending on your connection method.

If you aren’t using HA or an MQTT broker then you can’t do it.

3

Thanks Daryl,
I do understand any help on only my story is difficult.
Yes I,am using HA and also mqtt is installed.
The boards (A)with the display and the board(B) with the dallas sensor both in esphome.
So my question in a nutshell is it possible to display the sensor valeu from board(B) on the display on board(A) if possible howe to achief that?
Both boards are on the network.
I try templates no result.
If neede I can give some .yaml files and logfiles.
Like to hear.
Meanwhile i,am looking for a solution.
To me this issue look quit common.
Regards Theo

4

Assuming the API is used on your display device and the sensor from the remote device shows in HA correctly, you define a new text sensor on the display device. For a sensor named for example sensor.board_b_temp that comes from board B and appears in HA, you would define a new sensor on board A:

text_sensor:
  - platform: homeassistant
    id: temp_board_b
    entity_id: sensor.board_b_temp

That new sensor can then be displayed as normal.

5

Hi Daryl,
Thanks again for your reply.
I will follow your advise and make a text sensor.
Let you know if I succeeded.
Thanks.
Regards,
Theo

6

Hi Daryl,
After whole day puzzling still no succes. Tried your advice with a text_sensor no luck.
Quit a lot tried s.a. the yaml file compared with a yaml file on a esp8266 board which is connected to a max7219 display. ( same syntax all over)
Tried to read the raddeltat temp. in this display (7219)and it works.
Same programming lines on my st7735 board no succes.
This means that the raddeltat can be read from HA in one esp8266 board and NOT in the other esp8266 board. Connect for test purposes two the same boards on the displays. For clarity the raddeltat is connected to a thurth (3) board. That why my whish for remote read out.

BlockquoteINFO Reading configuration /config/esphome/lul.yaml…
INFO Detected timezone ‘Europe/Amsterdam’
INFO Starting log output from lul.local using esphome API
INFO Successfully connected to lul.local
[21:43:06][I][app:102]: ESPHome version 2022.3.1 compiled on Dec 16 2022, 21:37:20
[21:43:06][C][wifi:491]: WiFi:
[21:43:06][C][wifi:353]: Local MAC: 10:52:1C:01:F5:1F
[21:43:06][C][wifi:354]: SSID: [redacted]
[21:43:06][C][wifi:355]: IP Address: 192.168.1.84
[21:43:06][C][wifi:356]: BSSID: [redacted]
[21:43:06][C][wifi:358]: Hostname: ‘lul’
[21:43:06][C][wifi:360]: Signal strength: -55 dB ▂▄▆█
[21:43:06][C][wifi:364]: Channel: 11
[21:43:06][C][wifi:365]: Subnet: 255.255.255.0
[21:43:06][C][wifi:366]: Gateway: 192.168.1.254
[21:43:06][C][wifi:367]: DNS1: 192.168.1.254
[21:43:06][C][wifi:368]: DNS2: 0.0.0.0
[21:43:06][C][logger:233]: Logger:
[21:43:06][C][logger:234]: Level: DEBUG
[21:43:06][C][logger:235]: Log Baud Rate: 0
[21:43:06][C][logger:236]: Hardware UART: UART0
[21:43:06][C][spi:097]: SPI bus:
[21:43:06][C][spi:098]: CLK Pin: GPIO14
[21:43:06][C][spi:100]: MOSI Pin: GPIO13
[21:43:06][C][spi:102]: Using HW SPI: YES
[21:43:06][C][homeassistant.time:010]: Home Assistant Time:
[21:43:06][C][homeassistant.time:011]: Timezone: ‘CET-1CEST,M3.5.0,M10.5.0/3’
[21:43:06][C][st7735:376]: ST7735
[21:43:06][C][st7735:376]: Rotations: 0 °
[21:43:06][C][st7735:376]: Dimensions: 128px x 160px
[21:43:06][C][st7735:377]: Model: ST7735 BLACKTAB
[21:43:06][C][st7735:378]: CS Pin: GPIO15
[21:43:06][C][st7735:379]: DC Pin: GPIO4
[21:43:06][C][st7735:380]: Reset Pin: GPIO5
[21:43:06][D][st7735:381]: Buffer Size: 20480
[21:43:06][D][st7735:382]: Height: 160
[21:43:06][D][st7735:383]: Width: 128
[21:43:06][D][st7735:384]: ColStart: 0
[21:43:06][D][st7735:385]: RowStart: 0
[21:43:06][C][st7735:386]: Update Interval: 1.0s
[21:43:06][I][main:075]: Raw Value of wifisignal: -58
[21:43:06][I][main:076]: Raw Value of Rad delta temp: nan
[21:43:06][C][captive_portal:088]: Captive Portal:
[21:43:06][C][web_server:129]: Web Server:
[21:43:06][C][web_server:130]: Address: lul.local:80
[21:43:06][C][mdns:084]: mDNS:
[21:43:06][C][mdns:085]: Hostname: lul
[21:43:06][C][ota:085]: Over-The-Air Updates:
[21:43:06][C][ota:086]: Address: lul.local:8266
[21:43:06][C][ota:089]: Using Password.
[21:43:06][C][api:138]: API Server:
[21:43:06][C][api:139]: Address: lul.local:6053
[21:43:06][C][api:143]: Using noise encryption: NO
[21:43:06][C][wifi_signal.sensor:009]: WiFi Signal ‘WiFi Signal Sensor’
[21:43:06][C][wifi_signal.sensor:009]: Device Class: ‘signal_strength’
[21:43:06][C][wifi_signal.sensor:009]: State Class: ‘measurement’
[21:43:06][C][wifi_signal.sensor:009]: Unit of Measurement: ‘dBm’
[21:43:06][C][wifi_signal.sensor:009]: Accuracy Decimals: 0
[21:43:06][C][homeassistant.sensor:030]: Homeassistant Sensor ‘raddeltat’
[21:43:06][C][homeassistant.sensor:030]: State Class: ‘’
[21:43:06][C][homeassistant.sensor:030]: Unit of Measurement: ‘’
[21:43:06][C][homeassistant.sensor:030]: Accuracy Decimals: 1
[21:43:06][C][homeassistant.sensor:031]: Entity ID: ‘sensor.raddeltat’
[21:43:07][I][main:075]: Raw Value of wifisignal: -58
[21:43:07][I][main:076]: Raw Value of Rad delta temp: nan
[21:43:08][I][main:075]: Raw Value of wifisignal: -58
[21:43:08][I][main:076]: Raw Value of Rad delta temp: nan
[21:43:09][I][main:075]: Raw Value of wifisignal: -58
[21:43:09][I][main:076]: Raw Value of Rad delta temp: nan
[21:43:10][I][main:075]: Raw Value of wifisignal: -58
[21:4

From board with st7735

Blockquote
INFO Reading configuration /config/esphome/loopk.yaml…
INFO Detected timezone ‘Europe/Amsterdam’
INFO Starting log output from loopk.local using esphome API
INFO Successfully connected to loopk.local
[21:42:58][I][app:102]: ESPHome version 2022.3.1 compiled on Dec 16 2022, 21:16:41
[21:42:58][C][wifi:491]: WiFi:
[21:42:58][C][wifi:353]: Local MAC: 10:52:1C:01:F4:48
[21:42:58][C][wifi:354]: SSID: [redacted]
[21:42:58][C][wifi:355]: IP Address: 192.168.1.75
[21:42:58][C][wifi:356]: BSSID: [redacted]
[21:42:58][C][wifi:358]: Hostname: ‘loopk’
[21:42:58][C][wifi:360]: Signal strength: -51 dB ▂▄▆█
[21:42:58][C][wifi:364]: Channel: 11
[21:42:58][C][wifi:365]: Subnet: 255.255.255.0
[21:42:58][C][wifi:366]: Gateway: 192.168.1.254
[21:42:58][C][wifi:367]: DNS1: 192.168.1.254
[21:42:58][C][wifi:368]: DNS2: 0.0.0.0
[21:42:58][C][logger:233]: Logger:
[21:42:58][C][logger:234]: Level: DEBUG
[21:42:58][C][logger:235]: Log Baud Rate: 0
[21:42:58][C][logger:236]: Hardware UART: UART0
[21:42:58][C][spi:097]: SPI bus:
[21:42:58][C][spi:098]: CLK Pin: GPIO16
[21:42:58][C][spi:100]: MOSI Pin: GPIO5
[21:42:58][C][spi:102]: Using HW SPI: NO
[21:42:58][C][gpio.binary_sensor:015]: GPIO Binary Sensor ‘Switch2’
[21:42:58][C][gpio.binary_sensor:016]: Pin: GPIO2
[21:42:58][C][homeassistant.time:010]: Home Assistant Time:
[21:42:58][C][homeassistant.time:011]: Timezone: ‘CET-1CEST,M3.5.0,M10.5.0/3’
[21:42:58][C][rotary_encoder:159]: Rotary Encoder ‘rotary’
[21:42:58][C][rotary_encoder:159]: State Class: ‘’
[21:42:58][C][rotary_encoder:159]: Unit of Measurement: ‘steps’
[21:42:58][C][rotary_encoder:159]: Accuracy Decimals: 0
[21:42:58][C][rotary_encoder:159]: Icon: ‘mdi:rotate-right’
[21:42:58][C][rotary_encoder:160]: Pin A: GPIO12
[21:42:58][C][rotary_encoder:161]: Pin B: GPIO14
[21:42:58][C][rotary_encoder:173]: Restore Mode: Restore (Defaults to zero)
[21:42:58][C][rotary_encoder:177]: Resolution: 1 Pulse Per Cycle
[21:42:58][C][adc:062]: ADC Sensor ‘Brilliance’
[21:42:58][C][adc:062]: Device Class: ‘voltage’
[21:42:58][C][adc:062]: State Class: ‘measurement’
[21:42:58][C][adc:062]: Unit of Measurement: ‘V’
[21:42:58][C][adc:062]: Accuracy Decimals: 2
[21:42:58][C][adc:067]: Pin: GPIO17
[21:42:58][C][adc:094]: Update Interval: 10.0s
[21:42:58][C][dht:017]: DHT:
[21:42:58][C][dht:018]: Pin: GPIO0
[21:42:58][C][dht:020]: Auto-detected model: DHT22
[21:42:58][C][dht:027]: Update Interval: 60.0s
[21:42:58][C][dht:029]: Temperature ‘Living Room Temperature’
[21:42:58][C][dht:029]: Device Class: ‘temperature’
[21:42:58][C][dht:029]: State Class: ‘measurement’
[21:42:58][C][dht:029]: Unit of Measurement: ‘°C’
[21:42:58][C][dht:029]: Accuracy Decimals: 1
[21:42:58][C][dht:030]: Humidity ‘Living Room Humidity’
[21:42:58][C][dht:030]: Device Class: ‘humidity’
[21:42:58][C][dht:030]: State Class: ‘measurement’
[21:42:58][C][dht:030]: Unit of Measurement: ‘%’
[21:42:58][C][dht:030]: Accuracy Decimals: 0
[21:42:58][C][max7219DIGIT:050]: MAX7219DIGIT:
[21:42:58][C][max7219DIGIT:051]: Number of Chips: 6
[21:42:58][C][max7219DIGIT:052]: Number of Chips Lines: 1
[21:42:58][C][max7219DIGIT:053]: Chips Lines Style : 1
[21:42:58][C][max7219DIGIT:054]: Intensity: 0
[21:42:58][C][max7219DIGIT:055]: Scroll Mode: 0
[21:42:58][C][max7219DIGIT:056]: Scroll Speed: 200
[21:42:58][C][max7219DIGIT:057]: Scroll Dwell: 1000
[21:42:58][C][max7219DIGIT:058]: Scroll Delay: 1000
[21:42:58][C][max7219DIGIT:059]: CS Pin: GPIO4
[21:42:58][C][max7219DIGIT:060]: Update Interval: 1.0s
[21:42:58][I][main:103]: Raw Value of Brilliance: 0.003906
[21:42:58][I][main:104]: Raw Value of Living Romm Humidity: 39.600002
[21:42:58][I][main:105]: Raw Value of Living Room Temperature: 18.200001
[21:42:58][I][main:106]: Value of Rad delta temp: 22
[21:42:58][I][main:107]: Switch2:
[21:42:58][I][main:108]: rotary:
[21:42:58][C][captive_portal:088]: Captive Portal:
[21:42:58][C][web_server:129]: Web Server:
[21:42:58][C][web_server:130]: Address: loopk.local:80
[21:42:58

from board with 7219 8x8 dit matrix display.

All and all still not quit clear to me.

If some other logs can be of help please let me know.
Like to hear.
Kind regards,
Theo

7

Hello Daryl,

My device with the st7735 display is not showing in the HA device list I will have a look into that.
Regards,
Theo

8

Try adding it manually - but if it doesn’t show up in HA then the text sensor won’t work.

9

Hi Daryl,

Precicely this was happened.
Stupid me. Sorry to waist your time.
Finnaly I got it working hoeree.
Some where some how I overlooked the ““new device notification””.
Now cont. to finish the display with the wanted functions.
Any way thanks again. This is a lessons learned.
Kind regards,
Theo

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