Chapter 5 Resets, Interrupts, and General System Control
MC9S08QE128 MCU Series Reference Manual, Rev. 2
Freescale Semiconductor
107
5.8.10
System Clock Gating Control 1 Register (SCGC1)
This high page register contains control bits to enable or disable the bus clock to the TPMx, ADC, IICx,
and SCIx modules. Gating off the clocks to unused peripherals is used to reduce the MCU’s run and wait
currents. See
Section 5.7, “Peripheral Clock Gating
,” for more information.
NOTE
User software should disable the peripheral before disabling the clocks to
the peripheral. When clocks are re-enabled to a peripheral, the peripheral
registers need to be re-initialized by user software.
5
LVDV
Low-Voltage Detect Voltage Select — The LVDV bit selects the LVD trip point voltage (V
LVD
).
0 Low trip point selected (V
LVD
= V
LVDL
).
1 High trip point selected (V
LVD
= V
LVDH
).
4
LVWV
Low-Voltage Warning Voltage Select — The LVWV bit selects the LVW trip point voltage (V
LVW
).
0 Low trip point selected (V
LVW
= V
LVWL
).
1 High trip point selected (V
LVW
= V
LVWH
).
3
LVWIE
Low-Voltage Warning Interrupt Enable — This bit enables hardware interrupt requests for LVWF.
0 Hardware interrupt disabled (use polling).
1 Request a hardware interrupt when LVWF = 1.
Table 5-13. LVD and LVW Trip Point Typical Values
1
1
See the data sheet for minimum and maximum values.
LVDV:LVWV
LVW Trip Point
LVD Trip Point
0:0
V
LVWL
= 2.15 V
V
LVDL
= 1.84 V
0:1
V
LVWH
= 2.48 V
1:0
2
2
This setting is not recommended
V
LVWL
= 2.15 V
V
LVDH
= 2.15 V
1:1
V
LVWH
= 2.48 V
7
6
5
4
3
2
1
0
R
TPM3
TPM2
TPM1
ADC
IIC2
IIC1
SCI2
SCI1
W
Reset:
1
1
1
1
1
1
1
1
Figure 5-12. System Clock Gating Control 1 Register (SCGC1)
Table 5-12. SPMSC3 Register Field Descriptions (continued)
Field
Description
Содержание MC9S08QE128
Страница 2: ......
Страница 4: ......
Страница 49: ...Chapter 3 Modes of Operation MC9S08QE128 MCU Series Reference Manual Rev 2 50 Freescale Semiconductor ...
Страница 138: ...Chapter 6 Parallel Input Output Control MC9S08QE128 MCU Series Reference Manual Rev 2 138 Freescale Semiconductor ...
Страница 144: ...Chapter 7 Keyboard Interrupt S08KBIV2 MC9S08QE128 MCU Series Reference Manual Rev 2 144 Freescale Semiconductor ...
Страница 166: ...Chapter 8 Central Processor Unit S08CPUV4 MC9S08QE128 MCU Series Reference Manual Rev 2 166 Freescale Semiconductor ...
Страница 174: ...MC9S08QE128 MCU Series Reference Manual Rev 2 174 Freescale Semiconductor Analog Comparator S08ACMPV3 ...
Страница 202: ...12 bit Analog to Digital Converter S08ADCV1 MC9S08QE128 MCU Series Reference Manual Rev 2 202 Freescale Semiconductor ...
Страница 282: ...Serial Peripheral Interface S08SPIV3 MC9S08QE128 MCU Series Reference Manual Rev 2 282 Freescale Semiconductor ...
Страница 306: ...Timer PWM Module S08TPMV3 MC9S08QE128 MCU Series Reference Manual Rev 2 306 Freescale Semiconductor ...
Страница 320: ...Development Support MC9S08QE128 MCU Series Reference Manual Rev 2 320 Freescale Semiconductor ...