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Figure 1–2. oscillator and pll connection – Texas Instruments MSP50C6xx User Manual

Page 21

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Functional Description for the MSP50C614

1-7

Introduction to the MSP50C6xx

Figure 1–2. Oscillator and PLL Connection

MSP50P614
MSP50C6xx

OSCIN

OSCOUT

PLL

C(PLL) = 3300 pF

22 pF

22 pF

10 M

10 M

32.768 kHz

† Keep these components as close as possible to the OSCIN, OSCOUT, and PLL pins.

a) Crystal Reference Oscillator Connections

b) Resistor Trim Oscillator Connections

MSP50C6xx
MSP50P614

OSCIN

OSCOUT

PLL

R(RTO) = 470 k

1%†

C(PLL) = 3300 pF

† Keep these components as close as possible to the OSCIN, OSCOUT, and PLL pins.

The peripheral consists of five 8-bit wide general-purpose I/O ports, one 8-bit
wide dedicated input port, and one 16-bit wide dedicated output port. The
general-purpose I/O ports are bit-wise programmable as either
high-impedance inputs or as totem-pole outputs. They are controlled via
addressable I/O registers. The input-only port has a programmable pullup
option (100-k

minimum resistance) and a dedicated service interrupt. These

features make the input port especially useful as a key-scan interface.

A simple one-bit comparator is also included in the periphery. The comparator
is enabled by a control register, and its input pins are shared with two pins in
one of the general-purpose I/O ports.