NEC PD750008 - Manual (Page 245)

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CHAPTER 8 RESET FUNCTION
CHAPTER 8 RESET FUNCTION
The µPD750008 is reset with the external reset signal (RESET) or the reset signal received from the basic
interval timer/watchdog timer. When either reset signal is input, the internal reset signal is generated. Figure
8-1 shows the configuration of the reset circuit.
Figure 8-1. Configuration of Reset Functions
When the RESET signal is generated, all hardware is initialized as indicated in Table 8-1. Figure 8-2 shows
the reset operation timing.
Figure 8-2. Reset Operation by Generation of RESET Signal
Note The following two wait times can be selected by a mask option:
2 17 /f
X
(21.8 ms at 6.00 MHz, 31.3 ms at 4.19 MHz)
2 15 /f
X
(5.46 ms at 6.00 MHz, 7.81 ms at 4.19 MHz)
However, the µPD75P0016 dose not have a mask option and its wait time is fixed to 2 15 /f
X
.
WDTM
RESET Internal reset signal
Reset signal from basic
interval timer/watchdog timer
Internal bus
RESET signal is generated
Operating mode or
standby mode
HALT mode Operating mode
Internal reset operation
Wait Note
*
8