M30222 Datasheet, PDF (125/237 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

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Specifications in this manual are tentative and subject to change
MITSUBISHI MICROCOMPUTERS
M30222 Group
Rev. G
Clock Asynchronous Serial I/O Mode
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
(d) TxD, RxD I/O polarity reverse function (UART2)
This function is to reverse TXD pin output and RXD pin input. The level of any data to be input or output
(including the start bit, stop bit(s), and parity bit) is reversed. Set this function to “0” (not to reverse) for
NORMAL use.
(e) Bus collision detection function (UART2)
This function is to sample the output level of the TXD pin and the input level of the RXD pin at the rising edge
of the transfer clock; if their values are different, then an interrupt request occurs. Figure 1.99 shows the
example of detection timing of a bus collision (in UART mode).
Transfer clock ^{“H”}
“L”
TxD2 ^{“H”}
ST
“L”
RxD2 ^{“H”}
ST
“L”
Bus collision detection _{“1”}
interrupt request signal
“0”
Bus collision detection _{“1”}
interrupt request bit
“0”
Fig. 1.99. Detection timing of a bus collision (in UART mode)
SP
SP
ST : Start bit
SP : Stop bit
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