DSP音頻處理示例The benefits of real-time analysis provided by DSP/BIOS are often required in programs that
were engineered without it. When the program is not built from the ground up using the
DSP/BIOS kernel and real-time analysis features, the lack of familiarity prevents engineers
from reaping the benefits of this very powerful tool set, especially in the final stage of
development when real-time analysis is needed most. This application note provides an
example of the necessary steps required to utilize DSP/BIOS features in order to bring these
solutions to bear in an existing application.
The project KEIL_IODemo shows how to use memory allocation routines (malloc) and char I/O (printf, scanf) via a serial interface with the Keil ARM toolchain.
The I/O functions are adapted for the Analog Devices ADuC7000 series using the SERIAL.C module.
The example also shows the efficiency of the Keil CA ARM Compiler run-time library which is tuned for single chip systems.
UART I/O and Memory Allocation Example for GNU
The project GNU_IODemo shows how to use memory allocation routines (malloc) and char I/O (printf, scanf) via a serial interface with the GNU toolchain.
The I/O functions are adapted for the Analog Devices ADuC7000 series using the SERIAL.C module.
The example also shows the efficiency of the Keil CA ARM Compiler run-time library which is tuned for single chip systems.
This m-file displays the time waveform for the Gaussian pulse function and the first and second derivatives of the Gaussian pulse function for a 0.5 nanosecond pulse width. Other values of pulse widths may be used by changing fs,t,t1. The program uses the actual first and second derivative equations for the Gaussian pulse waveforms. The first derivative is considered to be the monocycle or monopulse as discussed in most papers. The second derivative is the waveform generated from a dipole antenna used in a UWB system. Other information is contained in the file.
he LPC932 can be used to create a Pulse Width Modulated PWM signal. That s an analog signal, with only 2 discrete levels, for example 0V and 5V and a constant period. The current value of this signal at a certain poiTnt of time is proportional to its Duty Cycle. That s the High Time during one period divided by the period. It can also be calculated as the average value during a particular period. That means after low pass filtering, (e.g. RC circuit) the signal becomes analog, with an actual value controlled by the microcontroller. The PWM functionality enables the LPC932 to control for example the speed of DC motors or the brightness of electric lighting.
Although there has been a lot of AVL tree libraries available now, nearly all of them are meant to work in the random access memory(RAM). Some of them do provide some mechanism for dumping the whole tree into a file and loading it back to the memory in order to make data in that tree persistent. It serves well when there s just small amount of data. When the tree is somewhat bigger, the dumping/loading process could take a lengthy time and makes your mission-critical program less efficient. How about an AVL tree that can directly use the disk for data storage ? If there s something like that, we won t need to read through the whole tree in order to pick up just a little bit imformation(a node), but read only the sectors that are neccssary for locating a certain node and the sectors in which that node lies. This is my initial motivation for writing a storage-media independent AVL Tree. However, as you step forth, you would find that it not only works fine with disks but also fine with memorys, too.
Displays CPU time usage, the list of processes (can be terminated) and the task which are running (can be close or switch to). Plus a little net traffic monitor and a disk status report.
ITU-T Recommendation V.90 98年9月版本
A DIGITAL MODEM AND ANALOGUE MODEM PAIR FOR USE ON THE PUBLIC SWITCHED TELEPHONE NETWORK (PSTN) AT DATA SIGNALLING RATES OF UP TO 56 000 bit/s DOWNSTREAM AND UP TO 33 600 bit/s UPSTREAM
Ever wanted to just type tail -f error_log on Windows?Envious of your Unix friends who can track changes to a file, in real time, as they happen?
Well, now with the Objektiv Tail for Win32, you ll be happily monitoring your log files like you ve never done before.
What s even better, you can track several files all at the same time with the patented "Multiple Document Interface"TM technology, with each file having its own, fabulous window.
Rotating shafts experience a an elliptical motion called whirl. It is important to decompose this motion into a forward and backward whil orbits. The current function makes use of two sensors to generate a bi-directional spectrogram. The method can be extended to any time-frequency distribution
％
％ compute the forward/backward Campbell/specgtrogram
％
％ INPUT:
％ y (n x 2) each column is measured from a different sensor
％ ///////
％ __
％ |s1| y(:,1)
％ |__|
％ __
％ / \ ________|/
％ | | | s2 |/ y(:,2)
％ \____/ --------|/
％
％ Fs Sampling frequnecy
％
％ OUTPUT:
％ B spectrogram/Campbel diagram
％ x x-axis coordinate vector (time or Speed)
％ y y-axis coordinate vector (frequency [Hz])
