upd78f0114hgb-8es-a Renesas Electronics Corporation., upd78f0114hgb-8es-a Datasheet - Page 338

• Manufacturer Part Number: upd78f0114hgb-8es-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

(2) Oscillation stabilization time select register (OSTS)
338
This register is used to select the high-speed system clock oscillation stabilization wait time when STOP mode is
released. The wait time set by OSTS is valid only after STOP mode is released when the high-speed system
clock is selected as the CPU clock. After STOP mode is released when the internal oscillation clock is selected
as the CPU clock, check the oscillation stabilization time using OSTC.
OSTS can be set by an 8-bit memory manipulation instruction.
RESET input sets OSTS to 05H.
Cautions 1. To set the STOP mode when the high-speed system clock is used as the CPU clock, set
Remark f
Address: FFA4H
Symbol
OSTS
2. Before setting OSTS, confirm with OSTC that the desired oscillation stabilization time has
3. If the STOP mode is entered and then released while the internal oscillation clock is being
4. The wait time when STOP mode is released does not include the time after STOP mode
XP
Figure 17-2. Format of Oscillation Stabilization Time Select Register (OSTS)
: High-speed system clock oscillation frequency
OSTS before executing a STOP instruction.
elapsed.
used as the CPU clock, set the oscillation stabilization time as follows.
The oscillation stabilization time counter counts only during the oscillation stabilization
time set by OSTS. Therefore, note that only the statuses during the oscillation stabilization
time set by OSTS are set to OSTC after STOP mode has been released.
release until clock oscillation starts (“a” below) regardless of whether STOP mode is
released by RESET input or interrupt generation.
OSTS2
7
0
0
0
0
1
1
Desired OSTC oscillation stabilization time
After reset: 05H
Other than above
OSTS1
6
0
0
1
1
0
0
CHAPTER 17 STANDBY FUNCTION
R/W
OSTS0
User’s Manual U16961EJ4V0UD
5
0
1
0
1
0
1
X1 pin voltage
waveform
2
2
2
2
2
Setting prohibited
11
13
14
15
16
/f
/f
/f
/f
/f
STOP mode release
XP
XP
XP
XP
XP
4
0
Oscillation stabilization time selection
a
3
0
Oscillation stabilization time set by OSTS
204.8 s
819.2 s
1.64 ms
3.27 ms
6.55 ms
f
XP
OSTS2
= 10 MHz
2
OSTS1
128 s
512 s
1.02 ms
2.04 ms
4.09 ms
1
f
XP
= 16 MHz
OSTS0
0