How many binary sensors can a Wemos D1 Mini handle?

bphillips921 · January 21, 2020, 3:46pm

@IngoNRW, is that code you posted the YAML that I would use in ESPhome if I used that 12c IO extender?

If so, if I daisy-chained another pcf8574 to the first one would my YAML code continue with

 - platform: gpio
    name: "Garten_Relais_8"
    id: garten_relais_8
    pin:
      pcf8574: pcf8574_hub
      #Use pin number 7
      number: 8
      #One of INPUT, INPUT_PULLUP or OUTPUT
      mode: OUTPUT
      inverted: true

 - platform: gpio
    name: "Garten_Relais_8"
    id: garten_relais_8
    pin:
      pcf8574: pcf8574_hub
      #Use pin number 7
      number: 9
      #One of INPUT, INPUT_PULLUP or OUTPUT
      mode: OUTPUT
      inverted: true

....

Or would I need to start over with the pin numbers and add some other code to differentiate the second pcf8574 in the daisy chain?

bphillips921 · January 21, 2020, 4:46pm

The more I think about it, would my code for daisy-chained pcf8574 hubs look more like this?

i2c:
  sda: D2
  scl: D1

pcf8574:
  - id: 'pcf8574_hub'
    address: 0x20
    pcf8575: False

- platform: gpio
    name: "Garten_Relais_1"
    id: garten_relais_1
    pin:
      pcf8574: pcf8574_hub
      # Use pin number 0
      number: 0
      # One of INPUT, INPUT_PULLUP or OUTPUT
      mode: OUTPUT
      inverted: true
      
  - platform: gpio
    name: "Garten_Relais_2"
    id: garten_relais_2
    pin:
      pcf8574: pcf8574_hub
      # Use pin number 1
      number: 1
      # One of INPUT, INPUT_PULLUP or OUTPUT
      mode: OUTPUT
      inverted: true

...................

pcf8574:
  - id: 'pcf8574_hub2'
    address: 0x21
    pcf8575: False
      
  - platform: gpio
    name: "Garten_Relais_4"
    id: garten_relais_4
    pin:
      pcf8574: pcf8574_hub2
      # Use pin number 0
      number: 0
      # One of INPUT, INPUT_PULLUP or OUTPUT
      mode: OUTPUT
      inverted: true

  - platform: gpio
    name: "Garten_Relais_5"
    id: garten_relais_5
    pin:
      pcf8574: pcf8574_hub2
      # Use pin number 1
      number: 1
      # One of INPUT, INPUT_PULLUP or OUTPUT
      mode: OUTPUT
      inverted: true

............................

pcf8574:
  - id: 'pcf8574_hub3'
    address: 0x22
    pcf8575: False

  - platform: gpio
    name: "Garten_Relais_7"
    id: garten_relais_7
    pin:
      pcf8574: pcf8574_hub3
      # Use pin number 0
      number: 0
      # One of INPUT, INPUT_PULLUP or OUTPUT
      mode: OUTPUT
      inverted: true

  - platform: gpio
    name: "Garten_Relais_8"
    id: garten_relais_8
    pin:
      pcf8574: pcf8574_hub3
      # Use pin number 1
      number: 1
      # One of INPUT, INPUT_PULLUP or OUTPUT
      mode: OUTPUT
      inverted: true

........................

IngoNRW · January 21, 2020, 7:06pm

yes that is true
You define first the Extender with his own Address (set with the jupmer) an a unique name .
Then you can define the GPIOs

bphillips921 · January 23, 2020, 4:23am

I received two pcf8574 boards today, I was able to get one of them to work with my Wemos D1 Mini, but when I daisy chain two of them, the Wemos D1 Mini doesn’t boot.

My connections from Wemos D1 Mini to first pcf8574
pcf8574 -> Wemos D1
vcc -> 3.3v
gnd -> G
SDA -> D2
SCL -> D1

On the first pcf8574 I’m using 0x20 address. All three address pins are to the right (on -). When just one pcf8574 is connected using the 0x20 address it works. When a second pcf8574 is connected using 0x21, or if the single pcf8574 is changed to address 0x21, the Wemos D1 Mini doesn’t boot.

To make sure I’m understanding addressing correctly, to get the 0x21 address I’m moving the top yellow pin (A2) to the left (+) and leaving the other two ins (A1 & A0) to the left (-). I’m using this table.

Here is my ESPhome YAML code

# pcf8574 configuration entry
i2c:
  sda: D2
  scl: D1

pcf8574:
  - id: 'pcf8574_hub'
    address: 0x20
    pcf8575: False
  - id: 'pcf8574_hub2'
    address: 0x21
    pcf8575: False

# Individual outputs
binary_sensor:
  - platform: gpio
    name: "PCF8574 Pin #0"
    pin:
      pcf8574: pcf8574_hub
      # Use pin number 0
      number: 0
      # One of INPUT, INPUT_PULLUP or OUTPUT
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #1"
    pin:
      pcf8574: pcf8574_hub
      number: 1
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #2"
    pin:
      pcf8574: pcf8574_hub
      number: 2
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #3"
    pin:
      pcf8574: pcf8574_hub
      number: 3
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #4"
    pin:
      pcf8574: pcf8574_hub
      number: 4
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #5"
    pin:
      pcf8574: pcf8574_hub
      number: 5
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #6"
    pin:
      pcf8574: pcf8574_hub
      number: 6
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #7"
    pin:
      pcf8574: pcf8574_hub
      number: 7
      mode: INPUT
      inverted: False

#Hub2
  - platform: gpio
    name: "PCF8574 Pin #0"
    pin:
      pcf8574: pcf8574_hub2
      # Use pin number 0
      number: 0
      # One of INPUT, INPUT_PULLUP or OUTPUT
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #1"
    pin:
      pcf8574: pcf8574_hub2
      number: 1
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #2"
    pin:
      pcf8574: pcf8574_hub2
      number: 2
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #3"
    pin:
      pcf8574: pcf8574_hub2
      number: 3
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #4"
    pin:
      pcf8574: pcf8574_hub2
      number: 4
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #5"
    pin:
      pcf8574: pcf8574_hub2
      number: 5
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #6"
    pin:
      pcf8574: pcf8574_hub2
      number: 6
      mode: INPUT
      inverted: False
  - platform: gpio
    name: "PCF8574 Pin #7"
    pin:
      pcf8574: pcf8574_hub2
      number: 7
      mode: INPUT
      inverted: False

oldsap · January 25, 2020, 7:29am

Sorry about this reply. i’ve retested it and it doesn’t work. SwitchTopic applies to all switches.
So same question as your original post:
“Is there a good way to differentiate between the GPIO pins when sending the MQTT message to HA?”
i tried using tele but it Teleperiod only goes down to 10sec. i need to be updated as soon as one of my magnetic reed switches turns on. Any update on this?

oldsap · January 26, 2020, 7:40am

SOLVED:
see this

IngoNRW · January 29, 2020, 11:04am

I use the PCF8574 with 5 V VCC

IngoNRW · January 29, 2020, 11:06am

you can conect it with serveral address settings and look into the log whtich adress found:

[12:05:18][C][i2c:028]: I2C Bus:
[12:05:18][C][i2c:029]: SDA Pin: GPIO4
[12:05:18][C][i2c:030]: SCL Pin: GPIO5
[12:05:18][C][i2c:031]: Frequency: 50000 Hz
[12:05:18][I][i2c:033]: Scanning i2c bus for active devices…
[12:05:18][I][i2c:040]: Found i2c device at address 0x20
[12:05:18][I][i2c:040]: Found i2c device at address 0x27
[12:05:18][I][i2c:040]: Found i2c device at address 0x39
[12:05:18][I][i2c:040]: Found i2c device at address 0x76
[12:05:18][C][pcf8574:021]: PCF8574:
[12:05:18][C][pcf8574:022]: Address: 0x20
[12:05:18][C][pcf8574:023]: Is PCF8575: NO

bphillips921 · January 31, 2020, 4:16am

@IngoNRW, do you have pull up resistors installed between SCL>3v and SDA>3v?

IngoNRW · January 31, 2020, 12:46pm

no
pure 5 V