This is my second guide following the guide for the MA-40. I had some asking for the MA-112 guide so here it is to the best of my writing abilities.
Note: This guide removes the connection for the factory IO board, making the MA-112 only controllable by the ESPHome interface. Performing these steps will leave the MA-112 with no permanent modifications, and restoring to factory operation is just re-opening the unit, removing the ESP32 module, and re-connecting the control board to the front IO panel.
The control board for the MA-112 is located in the front of the unit, requiring the removal of the large plastic housing panel that makes up the entire front of the unit. You’re on your own for this part though, it’s been about a year since I opened it up. @cwe5590 has noted in the MA-40 thread that the MA-112 requires a tri-wing bit to open.
Open the Control Board Box in the front of the unit to expose the Control Board.
Unplug the cable connecting the Interface Panel and Control Board from the Control Board. We will be using the following pins on this header (thanks again to @cwe5590 for confirming the pin functions):
+5V - ESP32 Dev Board Power
GND - ESP32 Dev Board GND
VSP- Fan Control (Analog Input ranging from 1.58V (1% On) to 2V (100% On))
FG - Speed Feedback for Motor (pulse)
ION - DIO for ION control
FG - Speed Feedback for Motor (pulse)
PC - Power Control
Plug Jumper Cables into this header for the listed pins:
Lastly, close up the Control Board Box and plug these cables into the ESP32 Dev Board using the following pins:
gpio26 to VSP
gpio25 to FG
gpio33 to PC
gpio27 to ION
5V to +5V
GND to GND
Use the following code for ESPHome (you might need to mess with the lambda expression for fan speed to fine tune the voltages for your ESP32 and MA-112):
esphome:
name: esphome-ma-112
friendly_name: MA-112
esp32:
board: esp32dev
framework:
type: arduino
# Enable logging
logger:
# Enable Home Assistant API
api:
encryption:
key: !secret encryption_key
ota:
password: !secret ota_password
wifi:
ssid: !secret wifi_ssid
password: !secret wifi_password
# Enable fallback hotspot (captive portal) in case wifi connection fails
ap:
ssid: "MA-112"
password:
captive_portal:
globals:
- id: filter_time
type: int
restore_value: yes
initial_value: '0'
interval:
- interval: 1min
then:
if:
condition:
fan.is_on: ma112
then:
- lambda: |-
id(filter_time) += 1;
sensor:
- platform: pulse_counter
pin: 25
name: "Motor RPM"
update_interval: 1s
- platform: template
name: Filter On Time
id: filter_time_disp
unit_of_measurement: "minutes"
device_class: "duration"
state_class: "measurement"
accuracy_decimals: 0
lambda: |-
return id(filter_time);
binary_sensor:
- platform: template
name: "Filter End of Life"
lambda: |-
if (id(filter_time) > 180000){
return true;
} else {
return false;
}
button:
- platform: template
name: "Reset Filter Life"
on_press:
lambda: |-
id(filter_time) = 0;
switch:
- platform: gpio
pin: 27
name: "Ion"
id: ion
- platform: gpio
pin: 33
name: "Power"
id: power
internal: true
output:
- platform: esp32_dac
pin: 26
id: fanspeed
- platform: template
id: custom_fan
type: float
write_action:
- if:
condition:
lambda: return ((state == 0));
then:
# action for off
- switch.turn_off: power
- output.turn_off: fanspeed
- switch.turn_off: ion
- if:
condition:
lambda: return ((state > 0));
then:
# action for on
- switch.turn_on: power
- output.turn_on: fanspeed
- output.set_level:
id: fanspeed
level: !lambda return (0.48 + (state * 0.13));
fan:
- platform: speed
id: ma112
output: custom_fan
name: "Fan"
speed_count: 100
Home Assistant dashboard should look similar to the following if all is right!
