Z8 Encore!® Motor Control Flash MCUs
Product Specification
26
threshold voltage) and forces the device into the Reset state. While the supply voltage
remains below the Power-On Reset voltage threshold (VPOR), the VBO holds the device in
the Reset state.
After the supply voltage again exceeds the Power-On Reset voltage threshold and stabi-
lized, the device progresses through a full System Reset sequence, as described in the
Power-On Reset section. Following Power-On Reset, the PORstatus bit in the Reset
Source register is set to 1. Figure 4 illustrates Voltage Brown-Out operation. Refer to the
On-Chip Peripheral AC and DC Electrical Characteristics section on page 265 for the
VBO and POR threshold voltages (VVBO and VPOR).
The Voltage Brown-Out circuit can be either enabled or disabled during STOP mode.
Operation during STOP mode is controlled by the VBO_AOOption Bit. Refer to the Option
Bits chapter for information on configuring VBO_AO.
VCC = 3.3V
VCC = 3.3V
VPOR
VVBO
Program
Execution
Voltage
Brown-Out
Program Execution
System Clock
Internal Precision
Oscillator
Internal RESET
Signal
Option Bit
Counter Delay
System Clock
Counter Delay
Figure 4. Voltage Brown-Out Reset Operation
Watch-Dog Timer Reset
If the device is in normal or HALT mode, the Watch-Dog Timer can initiate a System
Reset at time-out if the WDT_RESOption Bit is set to 1. This setting is the default (unpro-
grammed) setting of the WDT_RESOption Bit. The WDTstatus bit in the Reset Status and
Control Register is set to signify that the reset was initiated by the Watch-Dog Timer.
Reset and Stop-Mode Recovery
P R E L I M I N A R Y
PS024604-1005
ZILOG [ ZILOG, INC. ]
