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CHAPTER 5 PORT FUNCTIONS
User’s Manual U12697EJ3V0UM
5.2.2 Port 1
This is an 8-bit input-only port with no on-chip pull-up resistor.
Port 1 supports A/D converter analog input as an alternate function.
Figure 5-3 shows a block diagram of port 1.
Figure 5-3. Block Diagram of P10 to P17
RD
Internal bus
P10/ANI0 to
P17/ANI7
Alternate
function
RD: Port 1 read signal
Caution Do not execute a read instruction for port 1 when it is used as an analog input port (including
bit manipulation instructions) since port 1 can also be used as A/D converter analog input.
If middle voltage is input to an analog input pin while the port is being read, the middle voltage
will be read, possibly impairing the reliability of the device.
