Thanks very much for that orange-assistant.
The problem for me is I think I have some level of code-blindness, I really (and I’ve tried many times over the years) can’t seem to get to grips with it and at 66 I think it’s way past hoping it will happen now. ;-(
So I look at the code and maybe I’ve got ADHD, discalcula or some dyslexia but it rarely makes any sense. ;-(
I can generally follow a good walkthrough and can still do simple electronics design and my soldering is still pretty good, but coding it really is just like an alien language. ;-(
So unless the manual / instructions had exact and working examples of exactly what I need to do, the chances are it would never compile because of something obvious to many but completely transparent to me.
So I love the whole HA / ESP32 thing and I can sometimes get lucky and find some code that I can just tweak to suit my needs but unless I can, I’m beholden to those for whom it’s second nature and in the hope that I can repay them or others via something I can actually do. 
Anyroadup, in the hope that this works and someone wouldn’t mind sorting it for me, this is my current code:
esphome:
name: co2-sensor-2
platform: ESP32
board: "featheresp32"
# Enable Home Assistant API
api:
ota:
wifi:
ssid: !secret wifi_ssid
password: !secret wifi_password
# use_address: 192.168.0.207
manual_ip:
static_ip: 192.168.0.198
gateway: 192.168.0.100
subnet: 255.255.255.0
# Enable fallback hotspot (captive portal) in case wifi connection fails
ap:
ssid: "Co2-Sensor-2 Fallback Hotspot"
password: "munged"
captive_portal:
logger:
# CO2 sensor
uart:
rx_pin: 27
tx_pin: 26
baud_rate: 9600
# Dipslay driver: ST7789
spi:
clk_pin: GPIO18
mosi_pin: GPIO19
font:
- file: "Oswald-Light.ttf"
id: font_70
size: 70
glyphs: 0123456789 # Only used for CO2 level
- file: "Oswald-Light.ttf"
id: font_30
size: 30
color:
- id: color_black
red: 0%
green: 0%
blue: 0%
white: 0%
- id: color_green
red: 0%
green: 100%
blue: 0%
- id: color_yellow
red: 100%
green: 100%
blue: 0%
- id: color_orange
red: 100%
green: 55%
blue: 0%
- id: color_red
red: 100%
green: 0%
blue: 0%
- id: color_white
red: 100%
green: 100%
blue: 100%
display:
- platform: st7789v
id: my_display
backlight_pin: GPIO4
cs_pin: GPIO5
dc_pin: GPIO16
reset_pin: GPIO23
brightness: 100%
rotation: 90
pages:
# Page 1: Current CO2 levels
# 0 - 1000 -> Green
# 1000 - 1600 -> Yellow
# 1600 - 2000 -> Orange
# >2000 -> Red
- id: page1
lambda: |-
if(!id(co2_sensor_2).has_state() ){
it.print(
it.get_width()/2,
it.get_height()/2,
id(font_70),
color_white,
TextAlign::CENTER,
"Starting..."
);
return;
}
auto bg_color = id(color_black);
auto text_color = id(color_green);
auto co2 = id(co2_sensor_2).state;
if(co2 > 1000) text_color = id(color_yellow);
if(co2 > 1600) text_color = id(color_orange);
if(co2 > 2000){
text_color = id(color_white);
bg_color = id(color_red);
}
it.filled_rectangle(0, 0, it.get_width(), it.get_height(), bg_color);
it.printf(
it.get_width()/2,
it.get_height()/2,
id(font_70),
text_color,
TextAlign::CENTER,
"%.0f",
co2
);
# Page 2: WiFi information
- id: page2
lambda: |-
it.print(
0, 0,
id(font_30),
id(color_white),
"WiFi details"
);
it.printf(
0, 30,
id(font_30),
id(color_white),
"%s",
id(wifi_ssid).state.c_str()
);
it.printf(
0, 60,
id(font_30),
id(color_white),
"%s",
id(wifi_ip_addr).state.c_str()
);
switch:
- platform: gpio
pin: GPIO4
id: backlight
internal: true
sensor:
- platform: mhz19
co2:
name: "CO2 Sensor 2"
id: "co2_sensor_2"
temperature:
name: "CO2 sensor 2 temperature"
internal: true
update_interval: 60s
automatic_baseline_calibration: false
- platform: wifi_signal
name: "CO2 sensor 2 WiFi"
update_interval: 60s
text_sensor:
- platform: wifi_info
ip_address:
internal: true
id: wifi_ip_addr
ssid:
internal: true
id: wifi_ssid
binary_sensor:
# Button to cycle through pages on the display
- platform: gpio
pin:
number: GPIO35
inverted: true
id: button_1
on_click:
then:
- display.page.show_next: my_display
- component.update: my_display
# Button to toggle the backlight (for use at night)
- platform: gpio
pin:
number: GPIO0
inverted: true
id: button_2
on_click:
then:
- switch.toggle: backlight
button:
- platform: restart
name: "CO2 sensor 2 restart"
This is the error message I get when I try to update (or verify).
INFO Reading configuration /config/esphome/co2-sensor-2.yaml...
WARNING GPIO0 is a Strapping PIN and should be avoided.
Attaching external pullup/down resistors to strapping pins can cause unexpected failures.
See https://esphome.io/guides/faq.html#why-am-i-getting-a-warning-about-strapping-pins
Failed config
display.st7789v: [source /config/esphome/co2-sensor-2.yaml:81]
'model' is a required option for [display.st7789v].
platform: st7789v
id: my_display
backlight_pin: GPIO4
cs_pin: GPIO5
dc_pin: GPIO16
reset_pin: GPIO23
[brightness] is an invalid option for [display.st7789v]. Please check the indentation.
brightness: 100%
rotation: 90
pages:
- id: page1
lambda: |-
if(!id(co2_sensor_2).has_state() ){
it.print(
it.get_width()/2,
it.get_height()/2,
id(font_70),
color_white,
TextAlign::CENTER,
"Starting..."
);
return;
}
auto bg_color = id(color_black);
auto text_color = id(color_green);
auto co2 = id(co2_sensor_2).state;
if(co2 > 1000) text_color = id(color_yellow);
if(co2 > 1600) text_color = id(color_orange);
if(co2 > 2000){
text_color = id(color_white);
bg_color = id(color_red);
}
it.filled_rectangle(0, 0, it.get_width(), it.get_height(), bg_color);
it.printf(
it.get_width()/2,
it.get_height()/2,
id(font_70),
text_color,
TextAlign::CENTER,
"%.0f",
co2
);
- id: page2
lambda: |-
it.print(
0, 0,
id(font_30),
id(color_white),
"WiFi details"
);
it.printf(
0, 30,
id(font_30),
id(color_white),
"%s",
id(wifi_ssid).state.c_str()
);
it.printf(
0, 60,
id(font_30),
id(color_white),
"%s",
id(wifi_ip_addr).state.c_str()
);
