Z8F082ASH020SC Datasheet, PDF (37/244 Pages) Zilog, Inc. – Z8 Encore XP-R F08xA Series with eXtended Peripherals

Z8 Encore! XP^® F08xA Series
Product Specification
19
Reset and STOP Mode Recovery
Overview
The Reset Controller within the Z8 Encore! XP^® F08xA Series controls Reset and STOP
Mode Recovery operation and provides indication of low supply voltage conditions. In
typical operation, the following events cause a Reset:
• Power-On Reset (POR)
• Voltage Brown-Out (VBO)
• Watch-Dog Timer time-out (when configured by the WDT_RES Flash Option Bit to
initiate a reset)
• External RESET pin assertion (when the alternate RESET function is enabled by the
GPIO register)
• On-Chip Debugger initiated Reset (OCDCTL[0] set to 1)
When the device is in STOP mode, a STOP Mode Recovery is initiated by either of the
following:
• Watch-Dog Timer time-out
• GPIO Port input pin transition on an enabled STOP Mode Recovery source
Reset Types
The Z8 Encore! XP^® F08xA Series provides several different types of Reset operation.
STOP Mode Recovery is considered a form of Reset. Table 8 lists the types of Reset and
their operating characteristics. The System Reset is longer if the external crystal oscillator
is enabled by the Flash option bits, allowing additional time for oscillator start-up.
Table 8. Reset and STOP Mode Recovery Characteristics and Latency
Reset Characteristics and Latency
Reset Type
Control Registers
eZ8
CPU Reset Latency (Delay)
System Reset
Reset (as applicable) Reset 66 Internal Precision Oscillator Cycles
System Reset with Crystal Reset (as applicable)
Oscillator Enabled
Reset 5000 Internal Precision Oscillator Cycles
PS024705-0405
PRELIMINARY
Reset and STOP Mode Recovery