HD404629R Datasheet, PDF (49/157 Pages) Renesas Technology Corp – AS Microcomputer Incorporating a DTMF Generator Circuit

HD404629R Series
Notes: 1. Circuit constants differ by the different types of crystal oscillators, ceramic oscillators, and with
the stray capacitance of the board, so consult the manufacturer of the oscillator to determine the
circuit parameters.
2. The wiring between the OSC₁, OSC₂ (X1 and X2 pins), and the other elements should be as
short as possible, and must not cross other wiring. Refer to figure 28.
3. If not using a 32.768-kHz crystal oscillator, fix the X1 pin to V_CC and leave the X2 pin open.
Input/Output
The MCU has 42 input/output pins (D₀–D₉, R0₀–R7₃) and 2 input pins (D₁₀, D₁₁). The features are
described below.
• Ten pins (D₀–D₉) are high-current input/output pins.
• The D₁₀ and D₁₁, and R0₀–R7₃ input/output pins are multiplexed with peripheral function pins such as
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 R2₃/SO pin 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.
• Each input/output pin has a built-in pull-up MOS, which can be individually turned on or off by
software.
I/O buffer configuration is shown in figure 29, programmable I/O circuits are listed in table 23, and I/O pin
circuit types are shown in table 24.
Table 23 Programmable I/O Circuits
MIS3 (bit 3 of MIS)
0
DCD, DCR
0
1
PDR
0
1
0
1
CMOS buffer PMOS
—
—
—
On
NMOS
—
—
On
—
Pull-up MOS
—
—
—
—
Note: — indicates off status.
1
0
1
0
1
0
1
—
—
—
On
—
—
On
—
—
On
—
On
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