Texas Instruments TMS320DM643x manual Changing PLL Multiplier

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PLL1 Control

5.2.2.2Changing PLL Multiplier

If the PLL is not powered down (PLLPWRDN bit in PLLCTL is cleared to 0) and the PLL stabilization time is previously met (step 7 in Section 5.2.2.1), follow this procedure to change PLL1 multiplier. The recommendation is to stop all peripheral operation before changing the PLL multiplier, with the exception of the C64x+ DSP and DDR2. The C64x+ DSP must be operational to program the PLL controller. DDR2 operates off of the clock from PLLC2.

1.Before changing the PLL frequency, switch to PLL bypass mode:

a.Clear the PLLENSRC bit in PLLCTL to 0 to allow PLLCTL.PLLEN to take effect.

b.Clear the PLLEN bit in PLLCTL to 0 (select PLL bypass mode).

c.Wait for 4 MXI cycles to ensure PLLC switches to bypass mode properly.

2.Clear the PLLRST bit in PLLCTL to 0 (reset PLL).

3.Clear the PLLDIS bit in PLLCTL to 0 (enable the PLL) to allow PLL outputs to start toggling. Note that the PLLC is still at PLL bypass mode; therefore, the toggling PLL output does not get propagated to the rest of the device.

4.Program the required multiplier value in PLLM.

5.If necessary, program PLLDIV1, PLLDIV2, and PLLDIV3 registers to change the SYSCLK1, SYSCLK2, and SYSCLK3 divide values:

a.Check for the GOSTAT bit in PLLSTAT to clear to 0 to indicate that no GO operation is currently in progress.

b.Program the RATIO field in PLLDIV1, PLLDIV2, and PLLDIV3 with the desired divide factors. Note that the dividers must maintain a 1:3:6 ratio to satisfy the CLKDIV1, CLKDIV3, CLKDIV6 clock domain requirements. See the device-specific data manual for more details on Clock Domains. In addition, make sure in this step you leave the PLLDIV1.D1EN, PLLDIV2.D2EN, and PLLDIV3.D3EN bits set (default).

c.Set the GOSET bit in PLLCMD to 1 to initiate a new divider transition. During this transition, SYSCLK1, SYSCLK2, and SYSCLK3 are paused momentarily.

d.Wait for N number of PLLDIVn source clock cycles to ensure divider changes have completed. See Section 5.2.2.3 for the formula on calculating the number of cycles N.

e.Wait for the GOSTAT bit in PLLSTAT to clear to 0.

6.Wait for PLL to reset properly. See the device-specific data manual for PLL reset time.

7.Set the PLLRST bit in PLLCTL to 1 to bring the PLL out of reset.

8.Wait for PLL to lock. See the device-specific data manual for PLL lock time.

9.Set the PLLEN bit in PLLCTL to 1 to remove the PLL from bypass mode.

SPRU978E–March 2008

PLL Controller

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Contents Reference Guide Submit Documentation Feedback Contents PLL Controller Command Register Pllcmd Boot Modes ResetList of Figures List of Tables Submit Documentation Feedback About This Manual Read This FirstNotational Conventions Related Documentation From Texas InstrumentsTMS320C6000, C6000 are trademarks of Texas Instruments Introduction Peripherals Block DiagramIntroduction Components of the DSP Subsystem DSP Subsystem in TMS320DM643x DMPSubmit Documentation Feedback TMS320C64x+ Megamodule TMS320C64x+ CPU TMS320C64x+ Megamodule Block Diagram 1 L1P Controller Memory ControllersL1D L1P3 L2 Controller 2 L1D ControllerInternal DMA Idma External Memory Controller EMCInterrupt Controller Intc Power-Down Controller PDCInternal Peripherals Bandwidth Manager Submit Documentation Feedback Memory Map Memory Interfaces Overview System MemoryDSP Internal Memory L1P, L1D, L2 Memory MapExternal Memory Internal Peripherals1 DDR2 External Memory Interface Memory Interfaces OverviewExternal Memory Interface Asynchronous Emif InterfaceSubmit Documentation Feedback Overview Clock Domains Device ClockingClock Domains OverviewCore Domains System Clock Modes and Fixed Ratios for Core Clock DomainsHecc Overall Clocking DiagramExample PLL1 Frequencies and Dividers 27 MHZ Clock Input Core Frequency FlexibilityCore Voltage DividerExample PLL2 Frequencies Core Voltage = 3 DDR2/EMIF ClockPeripheral I/O Domain Clock 4 I/O DomainsVideo Processing Back End Possible Clocking Modes VPSSCLKCTL.MUXSEL Bit Clocking Mode DescriptionPLL Controller PLL1 Control PLL ModuleSteps for Changing PLL1/Core Domain Frequency Device Clock GenerationSystem PLLC1 Output Clocks PLLC1 Output Clock Used byInitialization to PLL Mode from PLL Power Down Changing PLL Multiplier Example 5-1. Calculating Number of Clock Cycles N Changing Sysclk DividersDDR PLLC2 Output Clocks PLL2 ControlPllout Output Clock Used bySteps for Changing PLL2 Frequency 2.1 DDR2 Considerations When Modifying PLL2 FrequencyInitialization to PLL Mode from PLL Power Down Changing PLL Multiplier Example 5-2. Calculating Number of Clock Cycles N PLL and Reset Controller Registers PLL and Reset Controller ListPLL and Reset Controller Base Address End Address Size PLL Controller RegistersReset Type Status Register Rstype Field Descriptions Reset Type Status Register RstypePeripheral ID Register PID Peripheral ID Register PID Field DescriptionsPLL Control Register Pllctl Field Descriptions PLL Control Register PllctlPLL Controller Divider 1 Register PLLDIV1 PLL Multiplier Control Register PllmPLL Multiplier Control Register Pllm Field Descriptions D1ENPLL Controller Divider 3 Register PLLDIV3 PLL Controller Divider 2 Register PLLDIV2D2EN D3ENOD1EN Oscillator Divider 1 Register OSCDIV1Bpden Bypass Divider Register Bpdiv13. Bypass Divider Register Bpdiv Field Descriptions PLL Controller Status Register Pllstat PLL Controller Command Register PllcmdGoset StableALN2 ALN1 PLL Controller Clock Align Control Register AlnctlALN3 ALN2SYS3 Plldiv Ratio Change Status Register DchangeSYS3 SYS2 SYS1 18. Clock Enable Control Register Cken Field Descriptions Clock Enable Control Register CkenObsen Auxen Obsen19. Clock Status Register Ckstat Field Descriptions Clock Status Register CkstatBpon Obson Auxon20. Sysclk Status Register Systat Field Descriptions Sysclk Status Register SystatSYS3ON SYS2ON SYS1ON SYS3ONPower and Sleep Controller Power and Sleep Controller PSC Integration Number Module Name Default Module State MDSTAT.STATE Power Domain and Module TopologyDM643x DMP Default Module Configuration Power Domain States Power Domain and Module StatesModule States Module StatesPower Domain State Transitions Local ResetExecuting State Transitions Module State TransitionsIcePick Emulation Support in the PSC IcePick Emulation CommandsPSC Interrupts Interrupt EventsModule State Emulation Events Local Reset Emulation EventsInterrupt Registers Interrupt Handling Power and Sleep Controller PSC RegistersPSC Registers Offset Register DescriptionInterrupt Evaluation Register Inteval Field Descriptions Peripheral Revision and Class Information Register PIDInterrupt Evaluation Register Inteval Module Error Clear Register 1 MERRCR1 Module Error Pending Register 1 MERRPR1Module Error Pending Register 1 MERRPR1 Field Descriptions Module Error Clear Register 1 MERRCR1 Field DescriptionsGOSTAT0 Power Domain Transition Command Register PtcmdPower Domain Transition Status Register Ptstat Pordone POR Power Domain Status 0 Register PDSTAT0State PordoneNext Power Domain Control 0 Register PDCTL014. Module Status n Register MDSTATn Field Descriptions Module Status n Register MDSTATn15. Module Control n Register MDCTLn Field Descriptions Module Control n Register MDCTLnEmuihbie Emurstie Lrst EmuihbieSubmit Documentation Feedback Power Management PSC and Pllc Overview Power Management Features DescriptionClock Management PLL Bypass and Power DownModule Clock ON/OFF Module Clock Frequency ScalingDSP Sleep Modes DSP Sleep Mode ManagementDSP Module Clock ON/OFF DSP Module Clock onDSP Module Clock Off 3.3 V I/O Power DownVideo DAC Power Down Submit Documentation Feedback Interrupt Controller Submit Documentation Feedback System Module Device Boot Configuration Status Device ConfigurationDevice Identification Pin Multiplexing ControlVpss Clock and DAC Control Timer Control3 DDR2 VTP Control HPI ControlBus Master DMA Priority Control Bandwidth ManagementTMS320DM643x DMP Master IDs DSP CFGBoot Control Edma Transfer Controller ConfigurationTMS320DM643x DMP Default Master Priorities DSP DMA DSP CFG EmacSubmit Documentation Feedback 10.1 Reset10.2 10.3Device Configurations at Reset Reset PinsReset Types Type Initiator EffectDSP Local Reset DSP ResetDSP Module Reset Software Reset Disable SwRstDisableSynchronous Reset SyncReset Boot Modes Submit Documentation Feedback Additions/Modifications/Deletions Revision HistoryTable A-1. Document Revision History Rfid Products ApplicationsDSP
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