Eight-way remote control transmitter circuit using CS901

The figure shows an eight-way remote control transmitter composed of CS901 module and digital encoder SM5262 (same as PT2262). Buttons SA1~SA8 and diodes VD1~VD13 form an eight-way matrix input circuit, which serves as eight encoding input circuits of the remote control transmitter. Since pins 7~13 of SM5262 are address/data common terminals, if they are used as data input terminals, the circuit has six data input terminals. When all of them are used as data inputs, a total of 26=64 can be formed, that is, 64-way remote control transmitters. Only four input terminals D1~D4 are used in this circuit, and it can form a 24=16-way remote control transmitter. In fact, this circuit only uses half of it, that is, eight channels, to form an eight-way remote control transmitter. The digital input codes of this eight-way transmitter are: SA1-0001, SA2-0010, SA3-0011, SA4-0100, SA5-0101, SA6-0110, SA7-0111. SA8-1000, the remaining codes 1001-1111 are not used.