Signal input circuit a

Signal input circuit: The signal input circuit includes two parts: the remote control signal
input circuit and the key signal input circuit
, as shown in the figure. The remote control input signal is processed by the remote control receiving head (X4) and the signal processing circuit composed of R9, wind and
C7. The processed signal is directly input to pin 27 of the microcontroller
in a series of continuous codes. The microcontroller determines the instructions input by the user based on the decoding program and outputs the corresponding control signal to the actuator.
    At the same time, there are two manual buttons Sl and S2 on the indoor unit. When the remote control fails or needs maintenance, you can use these two buttons to input instructions
to control and check the operation of the air conditioner. These two keys connect the zero level of the microcontroller
through the on-off mode of the mechanical switch, so that the command signal of the @ pin or @ pin forms a path, which can improve the ability of human-computer dialogue.
  The AUTO key is an automatic working switch, used to control the start and stop of indoor and outdoor units. Press it once and the air conditioner
will operate in automatic mode; press it again and it will stop running. The temperature setting standard is 27℃, and there is no timing control function. The TEST key is a debugging key, which can
detect the entire working process of the system based on the pre-programmed software program of the microcomputer.