LPC2148 PLL for Cpu and Peripheral Clock

PLL stands for Phase Locked Loop and is used to generate clock pulse given a reference clock input which is generally from a crystal oscillator(or XTAL). Configuring and using PLL in lpc124x MCUs is pretty simple and straight forward.

LPC2148 LED Interfacing

 

Blinky Example – Now we repeatedly make all pins in port 0 (P0.0 to P0.30) High then Low then High and so on. You can connect Led to some or all Pins on Port 0 to see it in action. Here we will introduce some delay between making all pins High and Low so it can be noticed.

Introduction to LPC2148 GPIO Programming

Most of the function oriented pins on lpc214x Microcontrollers are grouped into ports. lpc2148 has 2 ports viz. Port 0 and Port 1.

• Port 0 is a 32 bit wide I/O port (i.e it can be used for max 32 pins where each pin refers to a corresponding bit) and has dedicated direction bits for each of the pins present in the port. 28 out of the 32 pins can be used as bi-directional I/O (digital) pins. Pins P0.24 , P0.26 & P0.27 are unavailable for use and Pin P0.30 can be used as output pin only.

• Port 1 is also a 32 bit wide I/0 port but Pins 0 to 15 i.e P1.0 – P1.15 are unavailable for use and this port too has a dedicated direction bit for each of the usable pins.

Introduction to ARM7 Based Microcontroller (LPC2148)

ARM is a family of instruction set architectures for computer processors based on a reduced instruction set computing (RISC) architecture developed by British company ARM Holdings.

A RISC-based computer design approach means ARM processors require significantly fewer transistors than typical processors in average computers. This approach reduces costs, heat and power use. These are desirable traits for light, portable, battery-powered devices—including smartphones, laptops, tablet and notepad computers), and other embedded systems. A simpler design facilitates more efficient multi-core CPUs and higher core counts at lower cost, providing higher processing power and improved energy efficiency for servers and supercomputers.

 

LET’S START WITH LPC 2148

LPC2148 is the widely used IC from ARM-7 family. It is manufactured by Philips and it is pre-loaded with many inbuilt peripherals making it more efficient and a reliable option for the beginners as well as high end application developer.