EM78P5840N/41N/42N
8-Bit Microcontrollers
7.7 Reset
A Reset is initiated by one of the following conditions:
Power-on reset
WDT timeout (if enabled and in Green or Normal mode)
The Reset pin is pulled low (At P71S = 1)
Once a Reset occurs, the following functions are immediatley performed:
The oscillator continues to run, or will be started (if not already running)
The Program Counter (R2) is set to all "0"
When powered on, the upper three bits of R3 and the upper two bits of R4 are
cleared.
The Watchdog timer and prescaler counter are cleared.
The Watchdog timer is disabled.
7.8 Wake-Up
The controller provides a Sleep mode function to conserve power consumption by-
Sleep mode, RA(7) = 0 + "SLEP" instruction
In Sleep mode, the controller turns off all the CPU and crystal. Other power control
circuits can also be turned off, i.e., key tone control or PLL control (which has an
enable register) by software.
Wake-up is triggered from Sleep mode through one of the following conditions:
WDT Time-out
External interrupt
/RESET pull low
All of the above will reset the controller and run the program at Address 0. The result is
the same as that with power-on reset.
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Product Specification (V1.0) 04.25.2006
(This specification is subject to change without further notice)
ELAN [ ELAN MICROELECTRONICS CORP ]
