I/O Control Register And I/O Mode; Mask Option - Epson S1C6S3N2 Technical Manual

I/O control register
and I/O mode

Mask option

S1C6S3N2 TECHNICAL HARDWARE
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (I/O Ports)
Input or output mode can be set for the four bits of I/O port
P00–P03 and I/O port P10–P13 by writing data into the
corresponding I/O control register IOC0 and IOC1.
To set the input mode, "0" is written to the I/O control
register. When an I/O port is set to input mode, it becomes
high impedance status and works as an input port. How-
ever, the input line is pulled down when input data is read.
The output mode is set when "1" is written to the I/O control
register. When an I/O port set to output mode works as an
output port, it outputs a high signal (V
output data is "1", and a low signal (V
output data is "0".
At initial reset, the I/O control registers are set to "0", and
the I/O port enters the input mode.
The output specification during output mode (IOC = "1") of
these I/O ports can be set with the mask option for either
complementary output or Pch open drain output. This
setting can be performed for each bit of each port.
However, when Pch open drain output has been selected,
voltage in excess of the power voltage must not be applied to
the port.
EPSON
) when the port
DD
) when the port
SS
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