CLOCK & POWER MANAGEMENT
SC32442B RISC MICROPROCESSOR
7
-
8
FCLK, HCLK, and PCLK
FCLK is used by ARM920T.
HCLK is used for AHB bus, which is used by the ARM920T, the memory controller, the interrupt controller, the
LCD controller, the DMA and USB host block.
PCLK is used for APB bus, which is used by the peripherals such as WDT, IIS, I2C, PWM timer, MMC interface,
ADC, UART, GPIO, RTC and SPI.
The SC32442B supports selection of Dividing Ratio between FCLK, HLCK and PCLK. This ratio is determined by
HDIVN and PDIVN of CLKDIVN control register.
HDIVN PDIVN
HCLK3_HALF/
HCLK4_HALF
FCLK HCLK PCLK Divide
Ratio
0
0
-
FCLK
FCLK
FCLK
1 : 1 : 1
(Default)
0
1
-
FCLK
FCLK
FCLK / 2
1 : 1 : 2
1
0
-
FCLK
FCLK / 2
FCLK / 2
1 : 2 : 2
1
1
-
FCLK
FCLK / 2
FCLK / 4
1 : 2 : 4
3
0
0 / 0
FCLK
FCLK / 3
FCLK / 3
1 : 3 : 3
3
1
0 / 0
FCLK
FCLK / 3
FCLK / 6
1 : 3 : 6
3
0
1 / 0
FCLK
FCLK / 6
FCLK / 6
1 : 6 : 6
3
1
1 / 0
FCLK
FCLK / 6
FCLK / 12
1 : 6 : 12
2
0
0 / 0
FCLK
FCLK / 4
FCLK / 4
1 : 4 : 4
2
1
0 / 0
FCLK
FCLK / 4
FCLK / 8
1 : 4 : 8
2
0
0 / 1
FCLK
FCLK / 8
FCLK / 8
1 : 8 : 8
2
1
0 / 1
FCLK
FCLK / 8
FCLK / 16
1 : 8 : 16
After setting PMS value, it is required to set CLKDIVN register. The value set for CLKDIVN will be valid after PLL
lock time. The value is also available for reset and changing Power Management Mode.
The setting value can also be valid after 1.5 HCLK. Only, 1HCLK can validate the value of CLKDIVN register
changed from Default (1:1:1) to other Divide Ratio (1:1:2, 1:2:2, 1:2:4).
1 HCLK
1.5 HCLK
1.5 HCLK
0x00000000
0x00000001(1:1:2)
0x00000003 (1:2:4)
0x00000000 (1:1:1)
CLKDIVN
FCLK
HCLK
PCLK
Figure 7-6. Example of internal clock change
Содержание SC32442B54
Страница 1: ...SC32442B54 USER S MANUAL Revision 1 0 ...
Страница 43: ...PRODUCT OVERVIEW SC32442B RISC MICROPROCESSOR 1 42 NOTES ...
Страница 59: ...PROGRAMMER S MODEL SC32442B RISC MICROPROCESSOR 2 16 NOTES ...
Страница 123: ...ARM INSTRUCTION SET SC32442B RISC MICROPROCESSOR 3 64 NOTES ...
Страница 167: ...THUMB INSTRUCTION SET SC32442B RISC MICROPROCESSOR 4 44 NOTES ...
Страница 187: ...MEMORY CONTROLLER SC32442B RISC MICROPROCESSOR 5 20 NOTES ...
Страница 250: ...DMA SC32442B RISC MICROPROCESSOR 8 14 NOTES ...
Страница 308: ...PWM TIMER SC32442B RISC MICROPROCESSOR 10 20 NOTES ...
Страница 330: ...UART SC32442B RISC MICROPROCESSOR 11 22 NOTES ...
Страница 417: ...SC32442B RISC MICROPROCESSOR LCD CONTROLLER 15 45 NOTES ...
Страница 427: ...ADC AND TOUCH SCREEN INTERFACE SC32442B RISC MICROPROCESSOR 16 10 NOTES ...
Страница 511: ...BUS PRIORITIES SC32442B RISC MICROPROCESSOR 24 2 NOTES ...
Страница 562: ...K5D2G13ACM D075 Revision 1 0 December 2006 7 MCP MEMORY 2Gb 256Mb x8 NAND Flash Memory A Die ...
Страница 599: ...K5D2G13ACM D075 Revision 1 0 December 2006 44 MCP MEMORY 512Mb 16Mb x32 Mobile SDRAM C Die ...