Z8F1680SH020SG Datasheet, PDF (304/412 Pages) Zilog, Inc. – High-Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F1680 Series
Product Specification
279
Bit
Description (Continued)
[5:4]
Oscillator Mode Selection
OSC_SEL[1:0] 00 = On-chip oscillator configured for use with external RC networks or external clock
input (<4 MHz).
01 = Reserved.
10 = Medium power for use with medium frequency crystals or ceramic resonators
(1.0 MHz to 8.0 MHz).
11 = Maximum power for use with high-frequency crystals (8.0 MHz to 20.0 MHz). This
setting is default for unprogrammed (erased) Flash.
[3]
VBO_AO
Voltage Brown-Out Protection Always ON
0 = Voltage Brown-Out Protection is disabled in STOP Mode to reduce total power
consumption. And it is controlled by VBO/LVD control bit of Power Control Register in
ACTIVE and HALT Mode.
1 = Voltage Brown-Out Protection is always enabled including during STOP Mode. And it
cannot be disabled by VBO/LVD control bit of Power Control Register in any mode.
This setting is default for unprogrammed (erased) Flash.
[2]
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 default for unprogrammed (erased) Flash.
[1]
PRAM_M
On-Chip Program RAM Mode Select
0 = Program RAM is used as on-chip Register RAM and it begins at the first available
Register File address space. See the Register Map chapter on page 23.
1 = Program RAM is used as on-chip Program RAM and it begins at address E000H in
the Program Memory address space. This setting is default for unprogrammed
(erased) Flash.
[0]
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 are disabled. Mass Erase is
available using the On-Chip Debugger.
1 = Programming, Page Erase and Mass Erase are enabled for all of Flash program
memory.
PS025015-1212
PRELIMINARY
Flash Option Bits