May 8

Chapter1: Introduction to Microcontrollers

* Introduction
* 1.1 What are microcontrollers and what are they used for?
* 1.2 What is what in microcontroller?

Introduction

It was electricity in the beginning….The people were happy because they did not know that it was existing all around them and that it could be utilized. It was fine. And then Faraday came and the stone has started rolling slowly…

During the time, the first machines using a new sort of energy appeared accompanied with people who knew something about electricity. A long time has passed since then and just when civilization got used to this innovation and stopped paying attention to what a new generation of specialists were doing, someone came up with an idea that electrons could be a very convenient toy being closed in a glass pipe. At first sight, it was only a good idea, but there was no return, electonics was born and the stone continued rolling down the hill faster and faster…

A new science - new specialists. The blue coats were replaced with white ones and people who knew something about electronics appeared on stage. While the rest of the humanity were passively watching in disbelief what was going on, within plotters two fractions appeared- “software-oriented” and “hardware-oriented”. A bit younger than their teachers, very enthusiastic and full of ideas, both of them kept on working but separate ways. While the first group had a stable development, hardware-oriented people, driven by success, soon threw caution to the wind and invented transistor.
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Apr 13

Chapter 11: DSP Engine

* Introduction
* 11.1 X and Y data buses
* 11.2 PSV management
* 11.3 Multiplier
* 11.4 Barrel shifter
* 11.5 Adder
* 11.6 Round logic
* 11.7 Saturation logic
* 11.8 DSP instructions
* 11.9 DSP examples

Introduction

Digital signal processing (DSP) module is a part of the device specialized for fast execution of the basic mathematical operations (add, subtract, and multiply) and for performing automatically accumulation, logical shifting, rounding off, and saturation. This module makes the dsPIC30F devices very powerful and considerably extends the scope of their applications.

Processing of digital signals is very demanding. One of the biggest problems is the multiplication required for processing of digital signals. The family of dsPIC30F devices has a hardware implemented multiplier which accelerates considerably the processing. The major part of digital signal processing reduces to calculating the sums of products of two arrays. This module has been designed to allow a fast calculation of the sum of products:
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Apr 11

Chapter 3: Interrupts and Traps

* 3.1 Interrupts
* 3.2 Traps

3.1 Interrupts

Interrupts are unexpected events in a sequence of execution of instructions causing an interruption of the normal programme flow. The causes of interrupts can be different. For the family of dsPIC30F microcotrollers, in the transducer or general purpose applications, 41 interrupt sources and 4 types of traps, ranked according to the priority scheme, have been specified.

For each specified interrupt or trap the microcontroller (MCU) has a clearly defined further programme sequence specified by the interrupt vector table (IVT). The IVT contains the initial addresses of interrupt routines for each interrupt source or trap. IVT is located in the programme memory starting at location 0×000004 up to location 0×00007E.

In addition to the interrupt vestor table, in the family of dsPIC30F microcontrollers, the alterante interrupt vector table (AIVT) is also specified. The purpose of the AIVT is to enable the realization of alternate interrupt routines. The AIVT is also located in the programme memory starting at location 0×000084 up to location 0×0000FE.

On the basis of the priorities specified by the special function registers, the interrupt controller is responsible for the preparation and preprocessing of interrupts:
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