HD404639R Datasheet, PDF (44/135 Pages) Renesas Technology Corp – 4-Bit Single-Chip Microcomputer

HD404639R Series
Input/Output
The MCU has 61 input/output pins (D₀–D₁₁, R0₀–RC₀) and 7 input pins (D₁₂, D_13, RD₀–RD₃, RE ₀). The
features are described below.
• A maximum current of 15 mA is allowed for each of the pins D₄ to D₁₁ with a total maximum current of
less than 105 mA. In addition, D₀–D₃ can each act as a 10-mA maximum current source.
• Some input/output pins are multiplexed with peripheral function pins such as those for the timers or
serial interface. For these pins, the peripheral function setting is done prior to the D or R port setting.
Therefore, when a peripheral function is selected for a pin, the pin function and input/output selection
are automatically switched according to the setting.
• Input or output selection for input/output pins and port or peripheral function selection for multiplexed
pins are set by software.
• Peripheral function output pins are CMOS output pins. Only the R4₃/SO₁ and R5₃/SO₂ pins can be set to
NMOS open-drain output by software.
• In stop mode, the MCU is reset, and therefore peripheral function selection is cancelled. Input/output
pins are in high-impedance state.
• Pins D₀–D₃ have built-in pull-down MOS, and other input/output pins have built-in pull-up MOS, which
can be individually turned on or off by software.
I/O buffer configuration is shown in figure 27, programmable I/O circuits are listed in table 21, and I/O pin
circuit types are shown in table 22.
Table 21-1 Programmable I/O Circuits (with Pull-Up MOS)
MIS3 (Bit 3 of MIS)
0
1
DCD, DCR
0
1
0
1
PDR
0
1
0
1
0
1
0
1
CMOS buffer PMOS —
—
—
On
—
—
—
On
NMOS —
—
On
—
—
—
On
—
Pull-up MOS
—
—
—
—
—
On
—
On
Note: — indicates off status.
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