【導(dǎo)讀】Processing）來完成處理傳輸和解碼MP3文件的任務(wù)的。播放器的存儲(chǔ)設(shè)備。其中LPC2103實(shí)現(xiàn)對SD卡的讀寫、FAT32文件系。統(tǒng)的實(shí)現(xiàn)、txt文件的顯示、控制LCD的顯示及相關(guān)漢字庫的實(shí)現(xiàn)；解碼，從而完成MP3播放器的整體設(shè)計(jì)和實(shí)現(xiàn)。本次設(shè)計(jì)以分立芯片。來實(shí)現(xiàn)，這種設(shè)計(jì)更有利于對MP3播放器的分析和學(xué)習(xí)。身聽的數(shù)據(jù)傳輸，設(shè)備接口控制，文件解碼回放等活動(dòng)。也是它適合于便攜式播放器的一個(gè)顯著特點(diǎn)）。

　　

【正文】 ret。 if ((startaddr + blocknum) ) return SD_ERR_OVER_CARDRANGE。 if (SD_ChkCardWP() == 1) return SD_ERR_WRITE_PROTECT。 tmp = blocknum 。 while(tmp = 0) { ret = SD_EraseStartBlock(startaddr)。 if (ret != SD_NO_ERR) return ret。 ret = SD_EraseEndBlock(startaddr + 1)。 if (ret != SD_NO_ERR) return ret。 電子科技大學(xué)成都學(xué)院本科畢業(yè)設(shè)計(jì)論文 36 ret = SD_EraseSelectedBlock()。 if (ret != SD_NO_ERR) return ret。 startaddr += 。 blocknum = 。 tmp = blocknum 。 }。 if (blocknum 0) { ret = SD_EraseStartBlock(startaddr)。 if (ret != SD_NO_ERR) return ret。 ret = SD_EraseEndBlock(startaddr + blocknum 1)。 if (ret != SD_NO_ERR) return ret。 ret = SD_EraseSelectedBlock()。 if (ret != SD_NO_ERR) return ret。 } return SD_NO_ERR。 } endif INT8U SD_GetCardInfo() { 附 錄 37 INT32U receive。 INT8U csdbuf[16],ret。 ret = SD_ReadCSD(16,csdbuf)。 if (ret != SD_NO_ERR) return ret。 SD_CalTimeout(csdbuf)。 = 1 (csdbuf[READ_BL_LEN_POS] amp。 READ_BL_LEN_MSK)。 = ((csdbuf[C_SIZE_POS1] amp。 C_SIZE_MSK1) 10) + (csdbuf[C_SIZE_POS2] 2) + ((csdbuf[C_SIZE_POS3] amp。 C_SIZE_MSK3) 6) + 1。 receive = ((csdbuf[C_SIZE_MULT_POS1] amp。 C_SIZE_MULT_MSK1) 1) + ((csdbuf[C_SIZE_MULT_POS2] amp。 C_SIZE_MULT_MSK2) 7) + 2。 = * (1 receive)。 = ((csdbuf[SECTOR_SIZE_POS1] amp。 SECTOR_SIZE_MSK1) 1) + ((csdbuf[SECTOR_SIZE_POS2] amp。 SECTOR_SIZE_MSK2) 7) + 1。 return SD_NO_ERR。 }void SD_CalTimeout(INT8U *csdbuf) { INT32U tmp。 電子科技大學(xué)成都學(xué)院本科畢業(yè)設(shè)計(jì)論文 38 INT8U time_u,time_v,fator。 = READ_TIMEOUT_100MS。 = WRITE_TIMEOUT_250MS。 = WRITE_TIMEOUT_250MS。 time_u = (csdbuf[TAAC_POS] amp。 TAAC_MSK)。 time_v = (csdbuf[TAAC_POS] amp。 NSAC_MSK) 3。 fator = (csdbuf[R2WFACTOR_POS] amp。 R2WFACTOR_MSK) 2。 if(time_v == 0) return。 if(fator = 6) return。 tmp = SPI_CLOCK * time_value[time_v] / 10 / time_unit[time_u]。 tmp = tmp + csdbuf[NSAC_POS] * 100。 = tmp。 = tmp * r2w_fator[fator]。 = * 100 / 8。 = * 100 / 8。 if ( READ_TIMEOUT_100MS) = READ_TIMEOUT_100MS。 if ( WRITE_TIMEOUT_250MS) = WRITE_TIMEOUT_250MS。 = 。 } INT8U SD_ActiveInit(void) { INT8U param[4] = {0,0,0,0},resp[5],ret。 INT32U i = 0。 do } 外文資料 39 外文資料原文 LPC2101/2102/2103 General description The LPC2101/2102/2103 microcontrollers are based on a 16bit/32bit ARM7TDMISCPU with realtime emulation that bines the microcontroller with 8 kB, 16 kB or 32 kBof embedded highspeed flash memory. A 128bit wide memory interface and a unique accelerator architecture enable 32bit code execution at the maximum clock rate. For critical performance in interrupt service routines and DSP algorithms, this increases performance up to 30 % over Thumb mode. For critical code size applications, the alternative 16bit Thumb mode reduces code by more than 30 % with minimal performance penalty. Due to their tiny size and low power consumption, the LPC2101/2102/2103 are ideal for applications where miniaturization is a key requirement. A blend of serial munications interfaces ranging from multiple UARTs, SPI to SSP and two I2Cbuses, bined with onchip SRAM of 2 kB/4 kB/8 kB, make these devices very well suited for munication gateways and protocol converters. The superior performance also makes these devices suitable for use as math coprocessors. Various 32bit and 16bit timers, an improved 10bit ADC, PWM features through output match on all timers, and 32 fast GPIO lines with up to nine edge or level sensitive external interrupt pins make these microcontrollers particularly suitable for industrial control and medical systems. Key features * 16bit/32bit ARM7TDMIS microcontroller in a tiny LQFP48 package. * 2 kB/4 kB/8 kB of onchip static RAM and 8 kB/16 kB/32 kB of onchip flash program memory. 128bit wide interface/accelerator enables highspeed 70 MHz operation. * ISP/IAP via onchip bootloader software. Single flash sector or full chip erase in100 ms and programming of 256 bytes in 1 ms. * EmbeddedICE RT offers realtime debugging with the onchip 電子科技大學(xué)成都學(xué)院本科畢業(yè)設(shè)計(jì)論文 40 RealMonitor software. * The 10bit A/D converter provides eight analog inputs, with conversion times as low ms per channel and dedicated result registers to minimize interrupt overhead. * Two 32bit timers/external event counters with bined seven capture and seven pare channels. * Two 16bit timers/external event counters with bined three capture and seven pare channels. * Low power RealTime Clock (RTC) with independent power and dedicated 32 kHz clock input. * Multiple serial interfaces including two UARTs (16C550), two Fast I2Cbuses(400 kbit/s), SPI and SSP with buffering and variable data length capabilities. * Vectored interrupt controller with configurable priorities and vector addresses. * Up to thirtytwo 5 V tolerant fast general purpose I/O pins. * Up to 13 edge or level sensitive external interrupt pins available. * 70 MHz maximum CPU clock available from programmable onchip PLL with apossible input frequency of 10 MHz to 25 MHz and a settling time of 100 ms. * Onchip integrated oscillator operates with an external crystal in the range from 1 MHz to 25 MHz. * Power saving modes include idle mode, Powerdown mode with RTC active, and Powerdown mode. 外文資料 41 外文資料翻譯 LPC2101/2102/2103 簡介 LPC2101/02/03 是基于一個(gè)支持實(shí)時(shí)仿真的 16/32 位 ARM7 TDMIS CPU 的微控制器，并帶有 8kB,16kB 或 32kB 嵌入的高速 Flash 存儲(chǔ)器。128 位寬度的存儲(chǔ)器接口和獨(dú)特的加速結(jié)構(gòu)使 32 位代碼能夠在最大時(shí)鐘速率下運(yùn)行。對中斷服務(wù)程序和 DSP 算法中性能要求嚴(yán)格的應(yīng)用，這增加的性能比在 Thumb 模式下