M16C28 Datasheet, PDF (392/423 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/Tiny SERIES

M16C/28 Group (M16C/28, M16C/28B)
20. Precautions
20.11 Programmable I/O Ports
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1. If a low-level signal is applied to the SD pin when the IVPCR1 bit in the TB2SC register is set to “1”
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(three-phase output forcible cutoff by input on SD pin enabled), the P72 to P75, P80 and P81 pins go to
a high-impedance state.
2. The input threshold voltage of pins differs between programmable input/output ports and peripheral
functions.
Therefore, if any pin is shared by a programmable input/output port and a peripheral function and the
input level at this pin is outside the range of recommended operating conditions VIH and VIL (neither
“high” nor “low”), the input level may be determined differently depending on which side—the program-
mable input/output port or the peripheral function—is currently selected.
3. When the SM32 bit in the S3C register is set to "1", the P32 pin goes to high-impedance state. When
the SM42 bit in the S4C register is set to "1", the P96 pin goes to high-imepdance state.
4. When the INV03 bit in the INVC0 register is "1"(three-phase motor control timer output enabled), an "L"
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input on the P85 /NMI/SD pin, has the following effect.
•When the TB2SC register IVPCR1 bit is set to “1” (three-phase output forcible cutoff by input on
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SD pin enabled), the U/ U/ V/ V/ W/ W pins go to a high-impedance state.
•When the TB2SC register IVPCR1 bit is set to “0” (three-phase output forcible cutoff by input on
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SD pin disabled), the U/ U/ V/ V/ W/ W pins go to a normal port.
Therefore, the P85 pin can not be used as programmable I/O port when the INV03 bit is set to "1".
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When the SD function isn't used, set to "0" (Input) in PD85 and pullup to "H" in the P85 /NMI/SD pin from
outside.
Rev. 2.00 Jan. 31, 2007 ^{page 372} of 385
REJ09B0047-0200