HD6432351 Datasheet, PDF (695/989 Pages) Renesas Technology Corp – The H8S/2000 CPU has an internal 32-bit architecture, is provided with sixteen 16-bit general registers and a concise

Oscillator
ø
NMI
NMIEG
SSBY
NMI exception
Software standby mode
handling
(power-down mode)
NMIEG=1
SSBY=1
SLEEP instruction
Oscillation
stabilization
time t_OSC2
NMI exception
handling
Figure 20-2 Software Standby Mode Application Example
20.6.5 Usage Notes
I/O Port Status: In software standby mode, I/O port states are retained. If the OPE bit is set to 1,
the address bus and bus control signal output is also retained. Therefore, there is no reduction in
current dissipation for the output current when a high-level signal is output.
Current Dissipation during Oscillation Stabilization Wait Period: Current dissipation
increases during the oscillation stabilization wait period.
Write Data Buffer Function: The write data buffer function and software standby mode cannot
be used at the same time. When the write data buffer function is used, the WDBE bit in BCRL
should be cleared to 0 to cancel the write data buffer function before entering software standby
mode. Also check that external writes have finished, by reading external addresses, etc., before
executing a SLEEP instruction to enter software standby mode. See section 6.9, Write Data
Buffer Function, for details of the write data buffer function.
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