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【详解】如何编写Linux下Nand Flash驱动 v1.2.pdf33页
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【详解】如何编写Linux下Nand F lash驱动
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作者：crifan
邮箱:green-waste
正文之前...................................................................................................................................4
目的...........................................................................................................................4
目标读者和阅读此文的前提...................................................................................4
说明...........................................................................................................................4
声明...........................................................................................................................4
编写驱动之前要了解的知识...................................................................................................5
硬件特性...................................................................................................................5
什么是Flash .....................................................................................................5
Flash 的硬件实现机制.............................................................................5
什么是Nand Flash ...........................................................................................5
Nand Flash 和Nor Flash 的区别.............................................
正在加载中，请稍后...c#如何判断maskedtextbox1控件是否有输入值_百度知道
c#如何判断maskedtextbox1控件是否有输入值
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AssignedEditPositionCount如果未输入.maskedTextBox1.MaskedTextProviderthis
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//e.baidu://e.com/zhidao/wh%3D600%2C800/sign=cbcdad90c93d70cf4cafa20bc8ecfd38/00eecf1f9e7e36d12f2eb8389449.hiphotos。<img class="ikqb_img" src="http；否则，开始加载时就不会为空了，如图（）.baidu.hiphotos，就是空的://e.com/zhidao/wh%3D450%2C600/sign=2bcebaa1ba794fbfeecf1f9e7e36d12f2eb8389449.jpg" esrc="http.hiphotos！如果它的mask属性设置了
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你就判断那个maskedtextbox1的Text属性是否为空嘛
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出门在外也不愁PIC单片机的I2C应用程序1
14:02:58&&&来源:互联网 &&
File: an734.asm; data: feb.23.2001
; Functionality:;; This code implements the basic functions for an I2C slave device; using the SSP module. All I2C functions are hand in an ISR.; Bytes written to the slave are stored in a buffer. After a number; of bytes have been written, the master device can then read the; bytes back from the buffer.;; Variables and Constants used in the program:;; The start address for the receive buffer is stored in the variable; 'RXBuffer'. The length of the buffer is denoted by the constant; value 'RX_BUF_LEN'. The current buffer index is stored in the; variable 'Index'.;;--------------------------------------------------------------------;; The following files should be included in the MPLAB project:;; an734.asm-- Main source code file;; 16f872.lkr-- Linker script file; (change this file for the device; you are using);---------------------------------------------------------------------#include
; Change to device that you are using.;---------------------------------------------------------------------;Constant Definitions;---------------------------------------------------------------------#define NODE_ADDR 0x02 ; I2C address of this node; Change this value to address that; you wish to use.;---------------------------------------------------------------------; Buffer Length Definition;---------------------------------------------------------------------
#define RX_BUF_LEN 32 ; Length of receive buffer
;---------------------------------------------------------------------; Variable declarations;---------------------------------------------------------------------udata
WREGsave res 1STATUSsave res 1FSRsave res 1PCLATHsave res 1
Index res 1 ; Index to receive bufferTemp res 1 ;RXBuffer res RX_BUF_LEN ; Holds rec'd bytes from master; device.;---------------------------------------------------------------------; Vectors;---------------------------------------------------------------------
STARTUP codenopgoto Sta 0x0002 0x0003goto ISR ; 0x0004
;---------------------------------------------------------------------; Macros;---------------------------------------------------------------------
memset macro Buf_addr,Value,Length
movlw L This macro loads a range of data memorymovwf T with a specified value. The startingmovlw Buf_ address and number of bytes are alsomovwf FSR ; specified.SetNext movlw Valuemovwf INDFincf FSR,Fdecfsz Temp,Fgoto SetNextendm
LFSR macro Address,O This macro loads the correct valuemovlw A into the FSR given an initial datamovwf FSR ; memory address and offset value.movf Offset,Waddwf FSR,Fendm
;---------------------------------------------------------------------; Main Code;---------------------------------------------------------------------
Startupbcf STATUS,RP1bsf STATUS,RP0call Setup
M Clear the WDTgoto M Loop forever.
;---------------------------------------------------------------------; Interrupt Code;---------------------------------------------------------------------
ISRmovwf WREG Save WREGmovf STATUS,W ; Get STATUS registerbanksel STATUS Switch banks, if needed.movwf STATUS Save the STATUS registermovf PCLATH,W ;movwf PCLATH Save PCLATHmovf FSR,W ;movwf FSR Save FSR
banksel PIR1btfss PIR1,SSPIF ; Is this a SSP ?goto $ ; No, just trap here.bcf PIR1,SSPIFcall SSP_H Yes, service SSP interrupt.banksel FSRsavemovf FSRsave,W ;movwf FSR ; Restore FSRmovf PCLATHsave,W ;movwf PCLATH ; Restore PCLATHmovf STATUSsave,W ;movwf STATUS ; Restore STATUSswapf WREGsave,F ;swapf WREGsave,W ; Restore WREG Return from interrupt.;---------------------------------------------------------------------Setup;; Initializes program variables and peripheral registers.;---------------------------------------------------------------------
banksel PCONbsf PCON,NOT_PORbsf PCON,NOT_BOR
banksel I Clear various program variablesclrf Index
clrf PORTBclrf PIR1banksel TRISBclrf TRISB
movlw 0x36 ; Setup SSP module for 7-bitbanksel SSPCONmovwf SSPCON ; address, slave modemovlw NODE_ADDRbanksel SSPADDmovwf SSPADDclrf SSPSTATbanksel PIE1 ; Enable interruptsbsf PIE1,SSPIEbsf INTCON,PEIE ; Enable all peripheral interruptsbsf INTCON,GIE ; Enable global interrupts
bcf STATUS,RP0return
;---------------------------------------------------------------------SSP_Handler;---------------------------------------------------------------------; The I2C code below checks for 5 states:;---------------------------------------------------------------------; State 1: I2C write operation, last byte was an address byte.;; SSPSTAT bits: S = 1, D_A = 0, R_W = 0, BF = 1;; State 2: I2C write operation, last byte was a data byte.;; SSPSTAT bits: S = 1, D_A = 1, R_W = 0, BF = 1;; State 3: I2C read operation, last byte was an address byte.;; SSPSTAT bits: S = 1, D_A = 0, R_W = 1, BF = 0;; State 4: I2C read operation, last byte was a data byte.;; SSPSTAT bits: S = 1, D_A = 1, R_W = 1, BF = 0;; State 5: Slave I2C logic reset by NACK from master.;; SSPSTAT bits: S = 1, D_A = 1, R_W = 0, BF = 0;; For convenience, WriteI2C and ReadI2C functions have been used.;----------------------------------------------------------------------
banksel SSPSTATmovf SSPSTAT,W ; Get the value of SSPSTATandlw b'' ; Mask out unimportant bits in SSPSTAT.banksel T Put masked value in Tempmovwf T for comparision checking.
State1: ; Write operation, last byte was anmovlw b'' ; address, buffer is full.xorwf Temp,W ;btfss STATUS,Z ; Are we in State1?goto State2 ; No, check for next state.....memset RXBuffer,0,RX_BUF_LEN ; Clear the receive buffer.clrf I Clear the buffer index.call ReadI2C ; Do a dummy read of the SSPBUF.returnState2: ; Write operation, last byte was data,movlw b'' ; buffer is full.xorwf Temp,Wbtfss STATUS,Z ; Are we in State2?goto State3 ; No, check for next state.....LFSR RXBuffer,I Point to the buffer.call ReadI2C ; Get the byte from the SSP.movwf INDF ; Put it in the buffer.incf Index,F ; Increment the buffer pointer.movf Index,W ; Get the current buffer index.sublw RX_BUF_LEN ; Subtract the buffer length.btfsc STATUS,Z ; Has the index exceeded the buffer length?clrf I Yes, clear the buffer index.returnState3: ; Read operation, last byte was anmovlw b'' ; address, buffer is empty.xorwf Temp,Wbtfss STATUS,Z ; Are we in State3?goto State4 ; No, check for next state.....clrf I Clear the buffer index.LFSR RXBuffer,I Point to the buffermovf INDF,W ; Get the byte from buffer.call WriteI2C ; Write the byte to SSPBUFincf Index,F ; Increment the buffer index.returnState4: ; Read operation, last byte was data,movlw b'' ; buffer is empty.xorwf Temp,Wbtfss STATUS,Z ; Are we in State4?goto State5 ; No, check for next state....movf Index,W ; Get the current buffer index.sublw RX_BUF_LEN ; Subtract the buffer length.btfsc STATUS,Z ; Has the index exceeded the buffer length?clrf I Yes, clear the buffer index.LFSR RXBuffer,I Point to the buffermovf INDF,W ; Get the bytecall WriteI2C ; Write to SSPBUFincf Index,F ; Increment the buffer index.return
State5:movlw b'' ; A NACK was received when transmittingxorwf Temp,W ; data back from the master. Slave logicbtfss STATUS,Z ; is reset in this case. R_W = 0, D_A = 1goto I2CE and BF = 0 If we aren抰 in State5, then something is; wrong.
I2CErr nopbanksel PORTB ; Something went wrong! Set bsf PORTB,7 ; and loop forever. WDT will resetgoto $ ; device, if enabled.return
;---------------------------------------------------------------------; WriteI2C;---------------------------------------------------------------------
WriteI2Cbanksel SSPSTATbtfsc SSPSTAT,BF ; Is the buffer full?goto WriteI2C ; Yes, keep waiting.banksel SSPCON ; No, continue.DoI2CWritebcf SSPCON,WCOL ; Clear the WCOL flag.movwf SSPBUF ; Write the byte in WREGbtfsc SSPCON,WCOL ; Was there a write collision?goto DoI2CWritebsf SSPCON,CKP ; Release the clock.return
;---------------------------------------------------------------------ReadI2C;---------------------------------------------------------------------banksel SSPBUFmovf SSPBUF,W ; Get the byte and put in WREGreturn End of file
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cocos2d-x中CC_CALLBACK_0，CC_CALLBACK_1，CC_CALLBACK_2，CC_CALLBACK_3什么意思？怎么用？
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//a static method
Sprite* HelloWorld::maskedSpriteWithSprite(Sprite* textureSprite, Sprite* maskSprite)
RenderTexture * rt = RenderTexture::create( maskSprite-&getContentSize().width,
maskSprite-&getContentSize().height );
maskSprite-&setPosition(maskSprite-&getContentSize().width/2,
maskSprite-&getContentSize().height/2);
textureSprite-&setPosition(textureSprite-&getContentSize().width/2,
textureSprite-&getContentSize().height/2);
maskSprite-&setBlendFunc( BlendFunc{GL_ONE, GL_ZERO} );
textureSpri...
什么意思？
我今天也在看这个问题，这是我找到的适合小白的解释，应该比较难找到更通俗的了，有用请采纳，共同学习。
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出门在外也不愁}