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Peripheral Simulation

For NXP (founded by Philips) LPC1764 — Clocking & Power Control

Simulation support for this peripheral or feature is comprised of:

  • Dialog boxes which display and allow you to change peripheral configuration.

These simulation capabilities are described below.

Clock Dividers Dialog

Clock Dividers

The Clock Dividers dialog displays the registers and settings for the CPU and Peripheral clock supported by this device. The Peripheral Clock list allows you to specify a different clock divider for each peripheral.

CPU Clock Configuration

  • CCLKCFG (CPU Clock Configuration Register) contains the 8-bit divisor used to create the CCLK signal from the PLL output.
  • CCLKSEL (CPU Clock Configuration Selection) holds the 8-bit divisor value used to create the CCLK signal from the PLL output.
  • CCLK (CPU Clock) displays the resulting CPU clock value in MHz.

USB Clock Configuration

  • USBCLKCFG (USB Clock Configuration Register) contains the 4-bit divisor used to create the USBCLK signal from the PLL output.
  • USBSEL (USB Clock Configuration Selection) holds the 4-bit divisor value used to create the USBCLK signal from the PLL output.
  • USBCLK (USB Clock) displays the resulting USB clock value in MHz.

Peripheral Clock Selection

  • PCLK_xxx (Selected Peripheral Clock Register) selects the divisor that generates the Peripheral Clock PCLK from the Core Clock (CCLK).

Clock Generation Schematic Dialog

Clock Generation Schematic

The Clock Generation Schematic displays input clock values and the resulting generated clock values to be used by the application.

Clock generation Schematic

  • IRC is the on-chip 12 MHz oscillator.
  • XTAL is the value of the external crystal.
  • WDT is the watchdog timer source clock value.
  • MCLK is the generated main clock.
  • CCLK is the generated core clock.
  • SYSPLLCLKOUT is the resulting system PLL clock.
  • SYSPLLCLKIN is the input clock for the system PLL.

Phase Locked Loop 0 (PLL0) Dialog

Phase Locked Loop 0 (PLL0)

The Phase Locked Loop 0 Dialog controls Phase Locked Loop (PLL) function of the ARM controller. Using this dialog, you can configure the MCU clock frequency by changing the multiplier and divider values that control the MCU clock.

Control Register

  • PLL0CON (PLL Control Register) contains the PLL Enable bit (bit 0), and the PLL Connect bit (bit 1).
  • PLLE (PLL Enable) is set to activate the PLL and allow it to lock to the requested frequency.
  • PLLC (PLL Connect) is set to connect the PLL as the clock source. A successful connect requires the PLLE bit set.

Configuration Register

  • PLL0CFG (PLL Configuration Register) contains the PLL Multiplier (MSEL) and PLL Divider (PSEL) values.
  • MSEL (PLL Multiplier Value) is the multiplier value used in calculating the PLL clock frequency.
  • PSEL (PLL Divider Value) is the divider value used in calculating the PLL clock frequency.

Status Register

  • PLL0STAT (PLL Status Register) contains the following PLL status bits:
  • MSEL (PLL Multiplier Read-Back Value) is the multiplier value currently used by the PLL.
  • PSEL (PLL Divider Read-Back Value) is the divider value currently used by the PLL.
  • PLLE (PLL Enable Read-Back Value) is set when the PLL is active. If reset, the PLL is turned off.
  • PLLC (PLL Connect Read-Back Value) is set when the MCU uses the PLL as the clock source. If reset, the MCU uses the oscillator clock as the source.
  • PLOCK (PLL Lock Status) is set when the PLL is locked on the requested frequency.

Feed Register

  • PLL0FEED (PLL Feed Register) contains the 8-bit value last written to this register. To set the clock configuration, this register must be stored with consecutive values of 0xAA and 0x55, while the PLLE and PLLC bits are enabled.

Crystal Oscillator & Processor Clock

  • XTAL (Crystal Oscillator Frequency) the frequency (in MHz) of the crystal oscillator.
  • CLOCK (Processor Clock) is the computed processor clock frequency (CCLK) in MHz.

Phase Locked Loop 1 (PLL1) Dialog

Phase Locked Loop 1 (PLL1)

The Phase Locked Loop 1 Dialog controls Phase Locked Loop (PLL) function of the ARM controller. Using this dialog, you can configure the MCU clock frequency by changing the multiplier and divider values that control the MCU clock.

Control Register

  • PLL1CON (PLL Control Register) contains the PLL Enable bit (bit 0), and the PLL Connect bit (bit 1).
  • PLLE (PLL Enable) is set to activate the PLL and allow it to lock to the requested frequency.
  • PLLC (PLL Connect) is set to connect the PLL as the clock source. A successful connect requires the PLLE bit set.

Configuration Register

  • PLL1CFG (PLL Configuration Register) contains the PLL Multiplier (MSEL) and PLL Divider (PSEL) values.
  • MSEL (PLL Multiplier Value) is the multiplier value used in calculating the PLL clock frequency.
  • PSEL (PLL Divider Value) is the divider value used in calculating the PLL clock frequency.

Status Register

  • PLL1STAT (PLL Status Register) contains the following PLL status bits:
  • MSEL (PLL Multiplier Read-Back Value) is the multiplier value currently used by the PLL.
  • PSEL (PLL Divider Read-Back Value) is the divider value currently used by the PLL.
  • PLLE (PLL Enable Read-Back Value) is set when the PLL is active. If reset, the PLL is turned off.
  • PLLC (PLL Connect Read-Back Value) is set when the MCU uses the PLL as the clock source. If reset, the MCU uses the oscillator clock as the source.
  • PLOCK (PLL Lock Status) is set when the PLL is locked on the requested frequency.

Feed Register

  • PLL1FEED (PLL Feed Register) contains the 8-bit value last written to this register. To set the clock configuration, this register must be stored with consecutive values of 0xAA and 0x55, while the PLLE and PLLC bits are enabled.

Crystal Oscillator & Processor Clock

  • XTAL (Crystal Oscillator Frequency) the frequency (in MHz) of the crystal oscillator.
  • CLOCK (Processor Clock) is the computed processor clock frequency (CCLK) in MHz.

Power Control Dialog

Power Control

The Power Control Dialog controls the power saving mode of the ARM controller. With this dialog, you can selectively enable or disable unused peripherals to save power.

Power Control

  • PCON (Power Control Register) contains the DPDEN and DPDFLAG bits.
  • DPDEN (Deep Power-down Mode Enable) enables deep power-down mode when an ARM/Cortex-M0 WFI/WFE instruction is executed.
  • DPDFLAG (Deep Power-down Mode Flag) if set, indicates the device is in deep power-down mode.
  • GPREGn (General Purpose Register n) colds data retained during deep power-down mode. GPREG4 hold the WAKEUPHYS setting.
  • WAKEUPHYS (WAKEUP Pin Hysteresis Enable) if set, enables hysteresis for the WAKEUP pin.
Get more information about the
Peripheral Simulation Capabilities
of the µVision Debugger.
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