Z8 Encore! XP
®
4K Series
Product Specification
152
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 5.0MHz).
11 = Maximum power for use with high frequency crystals (5.0MHz 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.
FRP—Flash Read Protect
0 = User program code is inaccessible. Limited control features are available through the
On-Chip Debugger.
1 = User program code is accessible. All On-Chip Debugger commands are enabled. This
setting is the default for unprogrammed (erased) Flash.
Reserved—Must be 1.
FWP—Flash Write Protect
This Option Bit provides Flash Program Memory protection:
0 = Programming and erasure disabled for all of Flash Program Memory. Programming,
Page Erase, and Mass Erase through User Code is disabled. Mass Erase is available using
the On-Chip Debugger.
1 = Programming, Page Erase, and Mass Erase are enabled for all of Flash program mem-
ory.
Flash Program Memory Address 0001H
Table 90. Flash Options Bits at Program Memory Address 0001H
BITS
FIELD
RESET
R/W
ADDR
U
R/W
7
6
Reserved
U
R/W
U
R/W
5
4
XTLDIS
U
R/W
U
R/W
U
R/W
3
2
Reserved
U
R/W
U
R/W
1
0
Program Memory 0001H
Note: U = Unchanged by Reset. R/W = Read/Write.
Reserved—Must be 1.
XTLDIS—State of Crystal Oscillator at Reset:
PS022815-0206
Flash Option Bits
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