7 CLOCK GENERATOR (CLG)
7-16
Seiko Epson Corporation
S1C17651 TECHNICAL MANUAL
This is set to 1,024 cycles (OSC3A clock) after an initial reset.
When the system clock is switched to OSC3A immediately after the OSC3A oscillator circuit is turned
on, the OSC3A clock is supplied to the system after the OSC3A clock system supply wait time indi-
cated below (at a maximum) has elapsed.
OSC3A clock system supply wait time
≤ OSC3A oscillation start time (max.) + OSC3A os-
cillation stabilization wait time
Note: Oscillation stability will vary, depending on the resonator and other external components.
Carefully consider the OSC3A oscillation stabilization wait time before reducing the time.
D[3:2]
OSC1BWT[1:0]: OSC1B Stabilization Wait Cycle Select Bits
An oscillation stabilization wait time is set to prevent malfunctions due to unstable clock operation at
the start of OSC1B oscillation. The OSC1 clock is not supplied to the system immediately after OSC1B
oscillation starts until the time set here has elapsed.
8.11 OSC1B Oscillation Stabilization Wait Time Settings
Table 7.
OSC1BWT[1:0]
Oscillation stabilization wait time
0x3
8 cycles
0x2
16 cycles
0x1
32 cycles
0x0
64 cycles
(Default: 0x0)
This is set to 64 cycles (OSC1 clock) after an initial reset.
When the system clock is switched to OSC1 immediately after the OSC1B oscillator circuit is turned
on, the OSC1 clock is supplied to the system after the OSC1 clock system supply wait time indicated
below (at a maximum) has elapsed.
OSC1 clock system supply wait time
≤ OSC1B oscillation start time (max.) + OSC1B oscil-
lation stabilization wait time
D[1:0]
OSC1AWT[1:0]: OSC1A Stabilization Wait Cycle Select Bits
An oscillation stabilization wait time is set to prevent malfunctions due to unstable clock operation at
the start of OSC1A oscillation. The OSC1 clock is not supplied to the system immediately after OSC1A
oscillation starts until the time set here has elapsed.
8.12 OSC1A Oscillation Stabilization Wait Time Settings
Table 7.
OSC1AWT[1:0]
Oscillation stabilization wait time
0x3
2048 cycles
0x2
4096 cycles
0x1
8192 cycles
0x0
16384 cycles
(Default: 0x0)
This is set to 16384 cycles (OSC1 clock) after an initial reset.
When the system clock is switched to OSC1 immediately after the OSC1A oscillator circuit is turned
on, the OSC1 clock is supplied to the system after the OSC1 clock system supply wait time indicated
below (at a maximum) has elapsed.
OSC1 clock system supply wait time
≤ OSC1A oscillation start time (max.) + OSC1A oscil-
lation stabilization wait time
Note: Oscillation stability will vary, depending on the resonator and other external components.
Carefully consider the OSC1A oscillation stabilization wait time before reducing the time.