MSP430X41X_11 Datasheet, PDF (15/64 Pages) Texas Instruments – MIXED SIGNAL MICROCONTROLLER

MSP430x41x
MIXED SIGNAL MICROCONTROLLER
SLAS340J − MAY 2001 − REVISED DECEMBER 2008
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 MSP430x4xx Family User’s Guide, literature number
SLAU056.
oscillator and system clock
The clock system in the MSP430x41x family of devices is supported by the FLL+ module that includes support
for a 32768-Hz watch crystal oscillator, an internal digitally-controlled oscillator (DCO), and a high-frequency
crystal oscillator. The FLL+ clock module is designed to meet the requirements of both low system cost and low
power consumption. The FLL+ features a digital frequency locked loop (FLL) hardware which in conjunction
with a digital modulator stabilizes the DCO frequency to a programmable multiple of the watch crystal frequency.
The internal DCO provides a fast turn-on clock source and stabilizes in less than 6 μs. The FLL+ module
provides the following clock signals:
D Auxiliary clock (ACLK), sourced from a 32768-Hz watch crystal or a high frequency crystal.
D Main clock (MCLK), the system clock used by the CPU.
D Sub-Main clock (SMCLK), the subsystem clock used by the peripheral modules.
D ACLK/n, the buffered output of ACLK, ACLK/2, ACLK/4, or ACLK/8.
brownout, supply voltage supervisor
The brownout circuit is implemented to provide the proper internal reset signal to the device during power on
and power off. The supply voltage supervisor (SVS) circuitry detects if the supply voltage drops below a fixed
level or user selectable level (MSP430x415 & MSP430x417 only) and supports both supply voltage supervision
(the device is automatically reset) and supply voltage monitoring (SVM, the device is not automatically reset).
The CPU begins code execution after the brownout circuit releases the device reset. However, V_CC may not
have ramped to V_CC(min) at that time. The user must ensure the default FLL+ settings are not changed until V_CC
reaches V_CC(min). If desired, the SVS circuit can be used to determine when V_CC reaches V_CC(min).
digital I/O
There are six 8-bit I/O ports implemented—ports P1 through P6.
D All individual I/O bits are independently programmable.
D Any combination of input, output, and interrupt conditions is possible.
D Edge-selectable interrupt input capability for all the eight bits of ports P1 and P2.
D Read/write access to port-control registers is supported by all instructions.
Basic Timer1
Basic Timer1 has two independent 8-bit timers that can be cascaded to form a 16-bit timer/counter. Both timers
can be read and written by software. Basic Timer1 can be used to generate periodic interrupts and clock for the
LCD module.
LCD driver
The LCD driver generates the segment and common signals required to drive an LCD display. The LCD
controller has dedicated data memory to hold segment drive information. Common and segment signals are
generated as defined by the mode. Static, 2-MUX, 3-MUX, and 4-MUX LCDs are supported by this peripheral.
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