Dot-matrix character LCD module interface technology

Release time：[2011-12-21]     Views：9512

1) liquid crystal display module read / write operations are not directly use the microprocessor read / write signal to complete, but to use enable signal (E) positive pulse to complete, 89C51 microprocessor P1.0 port as a generator enable signal (E) of the strobe terminal.

2) because the liquid crystal display module of the data line is not three-state bus, so in the commissioning phase, R / W should be zero level, that is to write the state, if it is high, that is, reading the state, will cause confusion in the data bus. Because 89C51 microprocessor reset its port P1 was OFFH state, so the 89C51 microprocessor port P1.2 to go through the inverter output signal inverted, character liquid crystal display module is connected to the R / W input.