¡ Semiconductor
MSM6352
Input Port (I1-4)
Input only port that consists of 4 bits (I1, I2, I3, I4). The port status is determined by the input
instruction. Each input pin is pulled down to VSS (low level) through a transistor. The resistors
are connected only when the port status is determined or a low level signal is input.
Since the input current is limited, this port can be fixed at high level (VDD) for use.
I1
BUS 0
I2
VSS
BUS 1
I3
VSS
BUS 2
I4
VSS
VSS
BUS 3
Input instruction (IN 3, AP)
Figure 3. Input port (I1-I4) Configuration
HS Input Pin
HS 1-bit input pin, whose status can be fetched by the input instruction. It is pulled up to high
level (VDD) by a resistor and used as a hook switch input pin.
VDD
HS
BUS 0
Input instruction (IN 2, AP)
Figure 4. Configuration of HS Input Pin
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