spi firewall

After I wrote a simple SPI firewall program (only using IP filtering, but not packet filtering), I gave up research on SPI, however, a friend recently asked about the implementation of the SPI firewall, and now I will make a detailed analysis and summary of the

SPI interface SPI interface IntroductionSPI is a synchronous serial transmission specification released by Motorola. It is often used as a serial expansion interface for MCU peripheral chip. SPI has four pins: SS (from device Selection Line), SDO (serial data output line), SDI (serial data input line), and sck (synchronous serial clock line ).

Through the introduction of the previous article, we know that the SPI Universal interface layer is used to connect the specific SPI device protocol driver and SPI Controller driver, the general interface layer in addition to the protocol driver and controller driver to provide a series of standard interface APIs, but also for these interface API defines the corr

IICVsSPIToday, in low-end digital communications applications, we are seen in IIC (inter-integrated circuit) and SPI (Serial peripheral Interface). The reason is that these two communication protocols are ideal for near- low-speed inter-chip communication. Philips (for IIC) and Motorola (for SPI) have developed both standard communication protocols for different backgrounds and market requirements.IIC was d

Through the first article, we already know that the whole SPI drive architecture can be divided into three parts: Protocol driver, general interface layer and controller driver. The controller driver is responsible for the data sending and receiving work at the lowest level, in order to complete the data sending and receiving work, the controller driver needs to complete the following functions:1. Request the necessary hardware resources, such as inte

SPI, is the abbreviation of English serial Peripheral interface, as the name implies is the serial peripheral device interface. SPI, is a high-speed, full-duplex, synchronous communication bus, and on the chip's pin only occupies four lines, saving the chip pin, while the layout of the PCB space saving, convenient, it is for this simple and easy to use features, now more and more chips integrated this commu

Through the first article, we already know that the whole SPI drive architecture can be divided into three parts: Protocol driver, common interface layer and controller driver. Among them, the controller driver is responsible for the lowest data receiving and dispatching work, in order to complete the data receiving and dispatching, the controller driver needs to complete the following functions: 1. Apply for the necessary hardware resources, such as

We know that SPI data transfer can be in two ways: synchronous and asynchronous. The so-called synchronization means that the initiator of the data transmission must wait for the end of this transmission, can not do other things, in code to explain that, after the transfer function is called, until the data transfer completes, the function will return. The asynchronous approach is the opposite, the initiator of the data transmission without waiting fo

MCU simulation SPI interface-deep understanding of SPI bus protocol SPI (serial peripheral interfacer serial peripheral interface) is a synchronous serial communication interface launched by Motorola, the serial connection between the microprocessor compaction controller and the peripheral extended chip has developed into an industrial standard. Currently, variou

SPI communication details, spi communicationSPI data transmission and receiving Mechanism1 SPI OverviewSPI is a ring bus structure that operates in the master-slave mode. This mode usually has one master device and one or more slave devices and requires at least four lines (during Unidirectional transmission, the three lines can also be used), which is composed o

We know that SPI data transfer can be in two ways: synchronous and asynchronous. The so-called synchronization means that the originator of the data transfer must wait for the end of the transmission, the period can not do other things, in code to explain that the function is called after the transfer, until the data transfer is complete, the function will return. And the asynchronous way is just the opposite, the initiator of data transmission does n

#include "iospiflash.h"/*******************************************//This was a IOSPI (Simulater by IO)//Lib for Driver Flash W25Q64BV//*******************************************/Sbit ioflashspi_cs= p1^0;Sbit Ioflashspi_din = p1^3;Sbit ioflashspi_dout = p1^4;Sbit ioflashspi_clk = p1^5;/*******************************************//IOSPI Base FUNCData shifting at the--rising edge--of the CLKCLK need a Hold Time Mydelay (3)//ShiftWrite U8Read U8//1Time Series requires:The w25q64b Flash support the

Spring transaction SPI and configuration introduction, spring transaction spi Abstract of Spring transaction management. Three core interfaces are PlatformTransactionManager, TransactionDefinition, and TransactionStatus. Shows the link: TransactionDefinition:Defines Spring-compatible transaction attributes, including transaction isolation level, transaction Propagation Behavior, timeout duration, and read

Linux Device Driver inquiry 1st days ---- spi Driver (1), 1st days ---- spi This document allows reprinting. Please indicate the source:Http://blog.csdn.net/fulinus The Linux kernel code is too big, and a small module will make you feel helpless. This afternoon, I am determined to take a good look at the spi driver. First, analyze the spidev. c file, which define

From: http://www.cnblogs.com/liugf05/archive/2012/12/03/2800457.html There are two major modules below: One is SPI bus-driven analysis (the specific implementation process is studied) The other is the writing of the SPI bus driver (no need to study the specific implementation process) SPI bus driver analysis 1 SPI Ove

Editor's note: Unlike the traditional packet filtering firewall technology, this article starts with the application layer gateway technology and explores the use of WinSock2 SPI for network content access control. This is a new part of network security, or it provides a new idea for network security technology enthusiasts and R D personnel. Firewalls can implement and execute network access policies. Howe

Editor's note: In contrast to the traditional packet-filtering firewall technology, this paper probes into the problem of using WinSock2 SPI for network content access control from the application Layer Gateway technology. This is a new aspect of network security, or it provides a new way for enthusiasts and developers of network security technology. Firewalls can implement and execute network access polic

I. Overview Developing Drivers Based on subsystems is a common practice in Linux kernel. I have previously written about driver development based on the I2C subsystem. This article introduces another common bus SPI development method. The development of the SPI subsystem has many similarities with I2C, so you can compare and learn. This topic is divided into two parts. The first part introduces the theoreti

About I2C and SPI bus protocols Iicvs SPI Currently, in the low-end digital communication application field, we can see IIC (Inter-Integrated Circuit) and SPI (serial peripheral interface) everywhere. The reason is that these two communication protocols are very suitable for close-range and low-speed chip communication. Philips (for IIC) and Motorola (for

Stm32--spi InterfaceTenet: The learning of technology is limited and the spirit of sharing is limitless.First, SPI Agreement " serialperipheral Interface "Serial Peripheral interface, is a high-speed full-duplex communication bus. Communication between ADC/LCD and MCU.1 , SPI Signal LineThe SPI contains 4 buses, and th