The logic circuit in Figure 3-40 is used to enable the liquid crystal display (LCD) of a handheld electronic device when the microcontroller is sending data to or receiving data from the LCD controller. The circuit will enable the display when LCD = 1. Determine the input conditions necessary to enable the LCD.

Figure 3-40

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A₁ A₂ A3 A4 A5 As A7 A₂ IN OUT 74HC30 74HC02 W X Note: All gates are CMOS. 74HC32 74HC02 LCD