Datasheet

MSP430G22x0

www.ti.com

SLAS753E –JANUARY 2012–REVISED FEBRUARY 2013

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 (SLAU144).

Oscillator and System Clock

The clock system 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 and an internal digitally-controlled oscillator (DCO).

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 µs. The basic

clock module provides the following clock signals:

• Auxiliary clock (ACLK), sourced either from a 32768-Hz watch crystal or the internal LF (VLOCLK) oscillator.

• Main clock (MCLK), the system clock used by the CPU.

• Sub-Main clock (SMCLK), the sub-system clock used by the peripheral modules.

NOTE

The LFXT1 oscillator is not available. LFXT1Sx bits of the BCSCTL3 register should be

configured to use VLOCLK (see the MSP430x2xx Family User's Guide (SLAU144)).

Table 10. DCO Calibration Data (Provided From

Factory in Flash Information Memory Segment A)

DCO CALIBRATION

SIZE ADDRESS

FREQUENCY REGISTER

CALBC1_1MHZ byte 010FFh

1 MHz

CALDCO_1MHZ byte 010FEh

CALBC1_8MHZ byte 010FDh

8 MHz

CALDCO_8MHZ byte 010FCh

CALBC1_12MHZ byte 010FBh

12 MHz

CALDCO_12MHZ byte 010FAh

CALBC1_16MHZ byte 010F9h

16 MHz

CALDCO_16MHZ byte 010F8h

Brownout

The brownout circuit is implemented to provide the proper internal reset signal to the device during power on and

power off.

Digital I/O

There are four pins of one 8-bit I/O port implemented—port P1:

• All individual I/O bits are independently programmable.

• Any combination of input, output, and interrupt condition is possible.

• Edge-selectable interrupt input capability for all the four bits of port P1.

• Read/write access to port-control registers is supported by all instructions.

• Each I/O has an individually programmable pullup/pulldown resistor.