Epson S1C63358, Техническое руководство

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EPSON
S1C63358 TECHNICAL MANUAL
CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (Output Ports)
4.6 Output Ports
(R00–R03, R10–R13 and R20–R23)
4.6.1 Configuration of output ports
The S1C63358 has 12 bits 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 N-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
(R00–R03 are fixed at complementary output.)
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
R20–R23
Terminal status
at initial reset
R00 (High output)
R01 (High output)
R02 (High output)
R03 (High output)
R10–R13 (High output)
R20–R23 (High output)
Special output
TOUT FOUT
R00 R00
R01 R01
TOUT
FOUT
R10–R13 R10–R13
R20–R23 R20–R23
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 fixd at "0" (data output).
4.6.2 Mask option
Output specifications of the output ports can be selected with the mask option.
The output specifications of the output ports R10–R13 and R20–R23 can be selected from either comple-
mentary output or N-channel open drain output individually (in 4-bit units). The output ports R00–R03
can only be used as complementary output.
However, when N-channel open drain output is selected, do not apply a voltage exceeding the power
supply voltage to the output port.