MSP430F241X_11 Datasheet, PDF (19/107 Pages) Texas Instruments – MIXED SIGNAL MICROCONTROLLER

MSP430F241x, MSP430F261x
MIXED SIGNAL MICROCONTROLLER
SLAS541G -- JUNE 2007 -- REVISED MARCH 2011
flash memory
The flash memory can be programmed via the JTAG port, the bootstrap loader, or in-system by the CPU. The
CPU can perform single-byte and single-word writes to the flash memory. Features of the flash memory include:
D Flash memory has n segments of main memory and four segments of information memory (A to D) of
64 bytes each. Each segment in main memory is 512 bytes in size.
D Segments 0 to n may be erased in one step, or each segment may be individually erased.
D Segments A to D can be erased individually, or as a group with segments 0 to n.
Segments A to D are also called information memory.
D Segment A contains calibration data. After reset, segment A is protected against programming or erasing.
It can be unlocked, but care should be taken not to erase this segment if the calibration data is required.
D Flash content integrity check with marginal read modes
peripherals
Peripherals are connected to the CPU through data, address, and control buses and can be handled using all
instructions. For complete module descriptions, see the MSP430x2xx Family User’s Guide, literature number
SLAU144.
DMA controller
The DMA controller allows movement of data from one memory address to another without CPU intervention.
For example, the DMA controller can be used to move data from the ADC12 conversion memory to RAM. Using
the DMA controller can increase the throughput of peripheral modules. The DMA controller reduces system
power consumption by allowing the CPU to remain in sleep mode without having to awaken to move data to
or from a peripheral.
oscillator and system clock
The clock system in the MSP430x241x and MSP43x261x family of devices is supported by the basic clock
module that includes support for a 32768-Hz watch crystal oscillator, an internal very low-power low-frequency
oscillator, an internal digitally controlled oscillator (DCO), and a high-frequency crystal oscillator. The basic clock
module is designed to meet the requirements of both low system cost and low power consumption. The internal
DCO provides a fast turn-on clock source and stabilizes in less than 1 s. The basic clock module provides the
following clock signals:
D Auxiliary clock (ACLK), sourced from a 32768-Hz watch crystal, a high-frequency crystal, or a very
low-power LF oscillator
D Main clock (MCLK), the system clock used by the CPU
D Sub-Main clock (SMCLK), the subsystem clock used by the peripheral modules
The DCO settings to calibrate the DCO output frequency are stored in the information memory segment A.
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