HD404459 Datasheet, PDF (27/122 Pages) Renesas Technology Corp – 4-bit HMCS400-series microcomputers

HD404459 Series
Wakeup Function: Detects the falling edge of wakeup input signals and sets the wakeup interrupt request
flag (IFWU: $003, bit 2). Refer to figure 12 for a block diagram showing the wakeup interrupt. The wakeup
select register (WSR: $018) can select from one to eight wakeup inputs (WU₀–WU₇) (figure 13). The
wakeup function can operate in any mode other than stop mode. When the wakeup interrupt is received, the
CPU generates an independent vector address ($000E).
Note: The wakeup select register (WSR: $018) controls whether the wakeup input is to be valid or
invalid, but it can not switch the pin inputs between the R ports and wakeup. When using the pins
only as R ports, nullify wakeup input or set the wakeup interrupt mask (IMWU: $003, bit 3).
R5₀/WU₀
R5₁/WU₁
R5₂/WU₂
R5₃/WU₃
R6₀/WU₄
R6₁/WU₅
R6₂/WU₆
R6₃/WU₇
Falling-edge
detection
Wakeup
interrupt
request flag
4
WSR (4 bits)
Wakeup selection
register
4
Internal bus
Figure 12 Wakeup Interrupt
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