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EPSON
S1C63666 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)
4.6 Output Ports
(R00–R03 and R10–R13)
4.6.1 Configuration of output ports
The S1C63666 has eight bits of general output ports.
Output specifications of the output ports can be selected individually with the mask option. Two kinds of
output specifications are available: complementary output and P-channel open drain output.
Figure 4.6.1.1 shows the configuration of the output port.
V
DD
V
SS
Rxx
Data bus
Address
Data register
Address
High impedance
control register
Mask option
Fig. 4.6.1.1 Configuration of output port
The R02 and R03 output terminals are shared with special output terminals (TOUT, FOUT), and this
function is selected by the software.
At initial reset, these are all set to the general purpose output port.
Table 4.6.1.1 shows the setting of the output terminals by function selection.
Table 4.6.1.1 Function setting of output terminals
Terminal
name
R00
R01
R02
R03
R10–R13
Terminal status
at initial reset
R00 (Low output)
R01 (Low output)
R02 (Low output)
R03 (Low output)
R10–R13 (Low output)
Special output
TOUT
FOUT
R00
R00
R01
R01
TOUT
FOUT
R10–R13 R10–R13
When using the output port (R02, R03) as the special output port, the data register must be fixed at "1"
and the high impedance control register must be fixed at "0" (data output).
4.6.2 Mask option
Output specifications of the output ports are selected by mask option.
Either complementary output or P-channel open drain output can be selected individually (in 1-bit units).
However, when P-channel open drain output is selected, do not apply a voltage exceeding the power
supply voltage to the output port.
