In a preemptive priority based RTOS, priority inversion
problem is among the major sources of deadline
violations. Priority inheritance protocol is one of the
approaches to reduce priority inversion. Unfortunately,
RTOS like uC/OS can’t support priority inheritance
protocol since it does not allow kernel to have multiple
tasks at the same priority. Although it has different ways
to avoid priority inversion such as priority ceiling
protocol, developers still have some difficulties in
programming real time applications with it. In this paper,
we redesign the uC/OS kernel to provide the ability to
support round robin scheduling and implement priority
inheritance semaphore on the modified kernel. As result,
we port new kernel with priority inheritance semaphore to
evaluation board, and evaluate the execution time of each
of the kernel service as well as verify the operations of
our implementation.
This is a mutlicore and cluster(of single-core,multi-core systems) matrix inversion code.
Which uses the MPI(Message Passing Interface) for communication across the compute nodes of cluster and using thread-API based OpenMP(Open Multi Processing) between cores of intra-compute or head node.
DEMO_COND demonstrates the role of the condition
number of a matrix (with respect to inversion)
in the role of linear system solving.
Matthias Heinkenschloss
Department of Computational and Applied Mathematics
Rice University
Feb 22, 2001
A number of conventional solutions have been available forthe design of a DC/DC converter where the output voltageis within the input voltage range—a common scenarioin Li-Ion battery-powered applications—but none werevery attractive until now. Conventional topologies, suchas SEPIC or boost followed by buck, have numerousdisadvantages, including low effi ciency, complex magnetics,polarity inversion and/or circuit complexity/cost. TheLTC®3785 buck-boost controller yields a simple, effi cient,low parts-count, single-converter solution that is easyto implement, thus avoiding the drawbacks associatedwith traditional solutions.
The PCA9555 is a 24-pin CMOS device that provides 16 bits of General Purpose parallelInput/Output (GPIO) expansion for I2C-bus/SMBus applications and was developed toenhance the NXP Semiconductors family of I2C-bus I/O expanders. The improvementsinclude higher drive capability, 5 V I/O tolerance, lower supply current, individual I/Oconfiguration, and smaller packaging. I/O expanders provide a simple solution whenadditional I/O is needed for ACPI power switches, sensors, push buttons, LEDs, fans, etc.The PCA9555 consists of two 8-bit Configuration (Input or Output selection); Input, Outputand Polarity inversion (active HIGH or active LOW operation) registers. The systemmaster can enable the I/Os as either inputs or outputs by writing to the I/O configurationbits. The data for each Input or Output is kept in the corresponding Input or Outputregister. The polarity of the read register can be inverted with the Polarity inversionregister. All registers can be read by the system master. Although pin-to-pin and I2C-busaddress compatible with the PCF8575, software changes are required due to theenhancements, and are discussed in Application Note AN469.
The PCA9557 is a silicon CMOS circuit which provides parallel input/output expansion for
SMBus and I2C-bus applications. The PCA9557 consists of an 8-bit input port register,
8-bit output port register, and an I2C-bus/SMBus interface. It has low current consumption
and a high-impedance open-drain output pin, IO0.
The system master can enable the PCA9557’s I/O as either input or output by writing to
the configuration register. The system master can also invert the PCA9557 inputs by
writing to the active HIGH polarity inversion register. Finally, the system master can reset
the PCA9557 in the event of a time-out by asserting a LOW in the reset input.
The power-on reset puts the registers in their default state and initializes the
I2C-bus/SMBus state machine. The RESET pin causes the same reset/initialization to
occur without de-powering the part.
The CAT9534 is an 8-bit parallel input/output portexpander for I²C and SMBus compatible applications.These I/O expanders provide a simple solution inapplications where additional I/Os are needed: sensors,power switches, LEDs, pushbuttons, and fans.The CAT9534 consists of an input port register, anoutput port register, a configuration register, a polarityinversion register and an I²C/SMBus-compatible serialinterface.
This collection of C++ templates wraps the FORTRAN or C interfaces for LAPACK so that they integrate with the Boost uBLAS library. Currently implements Cholesky decomposition, LU decomposition, inversion and determinant for general and positive-definite matrices.
具體功能, A Free introduction on spring framework. 簡單地說，Spring 是一個以控制倒置(inversion of Control)原則為基礎的輕量級框架。控制倒置是一個用于“基于組件的體系結構”的設計模式，它將“判斷依賴關系”的職責移交給容器，而不是由組件本身來判斷彼此之間的依賴關系。當在Spring內實現組件時, 容器“輕量級”的方面就展現出來了：針對Spring開發的組件不需要任何外部庫；而且, 容器是輕量級的，它避免了像EJB容器那樣的重量級方案的主要缺點，例如啟動時間長、測試復雜、部署和配置困難，等等。
