Z8F0830HH020SG Datasheet, PDF (174/257 Pages) Zilog, Inc. – High-Performance 8-Bit Microcontrollers

Z8 Encore!^® F0830 Series
Product Specification
156
Normal Running
NO
Switch to OSC?
NO
Switch to IPO?
NO
Switch to WDT?
YES
YES
YES
NO
OSC is enabled?
Set bit6 in
OSCCTL register
and wait
1.5ms@20MHz
YES
Write to OSCCTL
register:
E7
18
to unlock OSCCTL
register
NO
Set bit7 in OSCCTL
register and wait
one NOP
instruction(wait
25 us if IPO
bandgap is closed)
IPO is enabled?
NO
YES
Set bit5 in OSCCTL
register and wait
50us
WDT OSC is
enabled?
YES
Write to OSCCTL register:
E7
18
to unlock OSCCTL
register
Write to OSCCTL register:
E7
18
to unlock OSCCTL
register
Write to OSCCTL
register:
010 to bits [2:0]
Write to OSCCTL register:
000 to bits [2:0]
Write to OSCCTL register:
011 to bits [2:0]
Figure 24. Oscillator Control Clock Switching Flow Chart
PS025113-1212
Oscillator Control Register Definitions