Infrared receiver circuit
Press the learning/control key to switch the CPU to the learning state. At this time, the learning status indicator D5 is on. When a device selection key is pressed, the program adjusts the data pointer (set by the program developer) to point to the data memory. When the start unit of a specified length data area is pressed simultaneously with a control key of the remote controller and a control key of the learned remote controller, the 8031 is controlled by the program to the P3.1 pin (ie, JR) outputs a low level (the original initialization program set it to a high level), and the level signal at the JR side is a control level of the NOR gate U1A. When P3.1=0, U1A output is the inverted signal of the input. That is, the infrared receiver circuit formed by D1.U4 is responsible for receiving the signal sent by the remote controller to be learned. When D1 has an infrared signal input, the signal is demodulated, shaped and amplified by U4 (the decoded pulse is inverted from the original encoding pulse. Bit) is output from pin 7 and is input to the P1.4 pin of the 8031 through the IN pin via the NOR gate U1A. The first high-level pulse of this signal is rapidly charged to C4 (reasonably selected R3, R4 Parameters to prevent repetitive triggering. At the same time, a falling edge signal is sent to the INT1 pin of the 8031 through the U2A IT pin. After the CPU responds to the interrupt, the U1A IN infrared coded signal is collected from the P14 to form a series of binary digits. It is stored in 8-bit units in the data area of the designated device and the designated key (error checking can be performed by one-shot bursts) to complete the learning of one key. If you learn the functions of other keys, the method is the same. If you want to learn the function of each key of another device, press another device selection key of this remote control, and then press each function control key respectively to learn the various functions of the remote control being learned.
Welcome to buy the universal ceiling fan remote control from our professional factory. As one of the certified China manufacturers and suppliers, we also offer the customized service and the wholesale service. Please be free to get the famous brands' products from us.