HD64F3437TFI16V Renesas Electronics America, HD64F3437TFI16V Datasheet - Page 581

• Manufacturer Part Number: HD64F3437TFI16V
• Description: MCU FLASH 60K 100-TQFP
• Manufacturer: Renesas Electronics America

Specifications of HD64F3437TFI16V

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

22.3.4
In this example the chip enters the software standby mode when NMI goes low and exits when
NMI goes high, as shown in figure 22.1.
The NMI edge bit (NMIEG) in the system control register is originally cleared to 0, selecting the
falling edge. When NMI goes low, the NMI interrupt handling routine sets NMIEG to 1, sets
SSBY to 1 (selecting the rising edge), then executes the SLEEP instruction. The chip enters
software standby mode. It recovers from software standby mode on the next rising edge of NMI.
Clock
oscillator
ø
NMI
NMIEG
SSBY
Sample Application of Software Standby Mode
Figure 22.1 NMI Timing in Software Standby Mode
NMI interrupt
handler
NMIEG = 1
SSBY = 1
SLEEP
Software standby
mode (power-
down state)
Settling time
NMI interrupt
handler
549