Z8F6421PM020SC Datasheet, PDF (211/299 Pages) Zilog, Inc. – High Performance 8-Bit Microcontrollers Z8 Encore-R 64K Series

Z8 Encore!^® 64K Series
Product Specification
191
Flash Memory Address 0000H
Table 97. Flash Option Bits At Flash Memory Address 0000H
BITS
7
6
5
4
3
2
FIELD ^{WDT_RES WDT_AO}
OSC_SEL[1:0]
VBO_AO
RP
RESET
U
R/W
R/W
ADDR
Program Memory 0000H
Note: U = Unchanged by Reset. R/W = Read/Write.
1
Reserved
0
FWP
WDT_RES—Watch-Dog Timer Reset
0 = Watch-Dog Timer time-out generates an interrupt request. Interrupts must be globally
enabled for the eZ8 CPU to acknowledge the interrupt request.
1 = Watch-Dog Timer time-out causes a Short Reset. This setting is the default for unpro-
grammed (erased) Flash.
WDT_AO—Watch-Dog Timer Always On
0 = Watch-Dog Timer is automatically enabled upon application of system power. Watch-
Dog Timer can not be disabled except during STOP Mode (if configured to power down
during STOP Mode).
1 = Watch-Dog Timer is enabled upon execution of the WDT instruction. Once enabled,
the Watch-Dog Timer can only be disabled by a Reset or STOP Mode Recovery. This set-
ting is the default for unprogrammed (erased) Flash.
OSC_SEL[1:0]—Oscillator Mode Selection
00 = On-chip oscillator configured for use with external RC networks (<4MHz).
01 = Minimum power for use with very low frequency crystals (32KHz to 1.0MHz).
10 = Medium power for use with medium frequency crystals or ceramic resonators
(0.5MHz to 10.0MHz).
11 = Maximum power for use with high frequency crystals (8.0MHz to 20.0MHz). This
setting is the default for unprogrammed (erased) Flash.
VBO_AO—Voltage Brown-Out Protection Always On
0 = Voltage Brown-Out Protection is disabled in STOP mode to reduce total power con-
sumption.
1 = Voltage Brown-Out Protection is always enabled including during STOP mode. This
setting is the default for unprogrammed (erased) Flash.
RP—Read Protect
0 = User program code is inaccessible. Limited control features are available through the
On-Chip Debugger.
PS019915-1005
Option Bits