Datasheet
MSP430C11x1, MSP430F11x1A
MIXED SIGNAL MICROCONTROLLER
SLAS241I − SEPTEMBER 1999 − REVISED DECEMBER 2008
11
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
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 MSP430x1xx Family User’s Guide, literature number
SLAU049.
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 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 6 μs. The basic clock 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
digital I/O
There are two 8-bit I/O ports implemented—ports P1 and P2 (only six P2 I/O signals are available on external
pins):
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 port P1 and six bits of port P2.
D Read/write access to port-control registers is supported by all instructions.
NOTE:
Only six bits of port P2 (P2.0 to P2.5) are available on external pins, but all control and data bits
for port P2 are implemented.
watchdog timer (WDT)
The primary function of the WDT module is to perform a controlled system restart after a software problem
occurs. If the selected time interval expires, a system reset is generated. If the watchdog function is not needed
in an application, the module can be configured as an interval timer and can generate interrupts at selected time
intervals.
Comparator_A
The primary function of the Comparator_A module is to support precision slope analog-to-digital conversions,
battery-voltage supervision, and monitoring of external analog signals.