MMC/SD卡以其優越的性能,在單片機嵌入式設備中得到廣泛應用。將MMC/SD卡作為外部掉電存儲介質應用于音頻信號發生器中,通過8051F330單片機上的SPI接口,實現單片機—MMC/SD卡的存儲擴展,設計了此硬件平臺上的MMC/SD卡的單片機驅動程序,并給出了相應的程序代碼,滿足音頻信號發生器的大容量存儲要求。 Abstract: MMC/SD card is more and more widely used in the single chip embedded devices for their excellent performances.This article introduces the application of MMC/SD card as the external power down storage medium in audio signal generator. The extension technology especially for storage of single chip-MMC/SD card via SPI interfaces in 8051F330 single chip, including designs single chip drive program of MMC/SD card based on hardware platform,and also gives the key coding of the program. The implementation of big capacity storage is meaningful in audio signal generator.
上傳時間: 2014-12-27
上傳用戶:黃華強
以AVR單片機ATmega8和USB接口器件PDIUSBD12為核心,基于標準的USB1.1協議,設計一種通用USB接口模塊,以滿足嵌入式系統中對USB接口的需求。對模塊的硬件電路或單片機固件程序的硬件接口層稍加修改即可用于其他各種微處理器。該模塊可為各種嵌入式系統增加USB接口,實現與USB主機系統通信。 Abstract: Based on AVR microcontroller ATmega8 and USB interface chip PDIUSBD12, a general USB interface module is designed according to USB1.1 protocol for various requirements of embedded systems. Only with few modifications in circuit or hardware abstract layer of firmware, the module can be used on many types of microprocessors. All kinds of embedded systems can realize high speed and stable communication with USB host systems, owing to the facility of this module.
上傳時間: 2014-01-08
上傳用戶:趙云興
介紹了MPC555與CS8900A擴展以太網的硬件設計圖。以NUCLUES PLUS操作系統為基礎,介紹了網卡軟件驅動程序的編制,給出了以太網協議包嵌入NUCLEUS PLUS操作系統的實現方法。 Abstract: The Ethernet extension hardware design of MPC555 and CS8900A are introduced,and the software driven program based on NUCLEUS PLUS operation system and the technique that Ethernet protocol embedded in NUCLEUS PLUS real operation system are discussed.
上傳時間: 2013-10-23
上傳用戶:xiehao13
Bootloader是微處理器上電時運行的第一段代碼,它可以通過通信接口實現對微處理器內部應用程序的更新升級,為網絡化嵌入式產品的應用程序升級帶來極大的便利。由于目前沒有統一嵌入式系統的Bootloader。基于NEC 78K0系列單片機自編程原理,設計出一個適用于78K0/Fx2系列單片機的Bootloader,并能夠通過單片機串口在線升級應用程序。 Abstract: Bootloader is the first piece of code executed after microprocessor startup. It makes the embedded product’s firmware update conveniently through communication interface. However, no unified bootloader is available for all kinds of microprocessor products. Based on the principle of self-programming NEC 78K0s’ series, a useful Bootloader which is suitable for 78K0/Fx2s’ series MCU is designed,the design can update the application through serial ports.
標簽: Bootloader MCU 自編程
上傳時間: 2013-10-26
上傳用戶:fang2010
隨著技術的發展,單片機開發手段也越來越先進,而價格卻不斷下降。當FLASH型單片機被廣泛應用后,采用軟件模擬加寫片驗證成為一種經濟實用的實驗方法。而近年來很多單片機都具有了ISP功能,只要一根下載線即可以編程,不再需要編程器。 美國SST公司推出的SST系列單片機更是集成了仿真功能,配合Keil軟件,可使用戶的目標板直接具有仿真功能,將單片機的易用性推向一個新的高度。 SST89E564RD是美國SST公司推出的一款內嵌89C52核的單片機,除具有89C52的所有資源外,還增加了768字節的XRAM(地址范圍100H-2FFH);增加了64KBlock0的Flash(地址范圍:0000H-FFFFH),原89C52的8KFlash為Block1,占用10000H-11FFFH的地址空間。出廠時SST89E564RD中已經固化與Keil連接的仿真軟件SoftICE,該Firmware與Keil一起可將C或匯編生成的代碼通過串口直接下載到Block0中,且可在線調試,該軟件占用Block1的前4K和Block0的后1KFlash空間,調試時占用串口和定時器2。
上傳時間: 2014-12-27
上傳用戶:uuuuuuu
導言基于FLASH存儲器的微處理器,一個重要的需求是安裝到產品中后,仍具有升級固件(firmware)的能力。這種能力稱為“在應用中編程”(In-application-programming,IAP)。這篇應用筆記以STM32F32位cortex-M3為例,闡述了構建IAP系統的一些通用概念。并提出了一種新的技術,有助于單片機開發人員更好的構建IAP系統。STM32系列微處理器基于FLASH存儲器。在FLASH中運行的固件可以擦寫FLASH本身。FLASH的頭4KB具有寫保護,適合存儲IAP固件(IAP BootLoader)。
上傳時間: 2013-11-07
上傳用戶:lalaruby
The PCA9516 is a BiCMOS integrated circuit intended forapplication in I2C and SMBus systems.While retaining all the operating modes and features of the I2Csystem, it permits extension of the I2C-bus by buffering both the data(SDA) and the clock (SCL) lines, thus enabling five buses of 400 pF.The I2C-bus capacitance limit of 400 pF restricts the number ofdevices and bus length. Using the PCA9516 enables the systemdesigner to divide the bus into five segments off of a hub where anysegment to segment transition sees only one repeater delay.
上傳時間: 2013-11-21
上傳用戶:q123321
The PCA9517 is a CMOS integrated circuit that provides level shifting between lowvoltage (down to 0.9 V) and higher voltage (2.7 V to 5.5 V) I2C-bus or SMBus applications.While retaining all the operating modes and features of the I2C-bus system during thelevel shifts, it also permits extension of the I2C-bus by providing bidirectional buffering forboth the data (SDA) and the clock (SCL) lines, thus enabling two buses of 400 pF. Usingthe PCA9517 enables the system designer to isolate two halves of a bus for both voltageand capacitance. The SDA and SCL pins are over voltage tolerant and arehigh-impedance when the PCA9517 is unpowered.
標簽: translating Level 9517 PCA
上傳時間: 2013-12-25
上傳用戶:wsf950131
The PCA9518 is a BiCMOS integrated circuit intended forapplication in I2C and SMBus systems.While retaining all the operating modes and features of the I2Csystem, it permits extension of the I2C-bus by buffering both thedata (SDA) and the clock (SCL) lines, thus enabling virtuallyunlimited buses of 400 pF.
標簽: Expandable 5channel 9518 PCA
上傳時間: 2013-10-23
上傳用戶:dumplin9
The PCA9519 is a 4-channel level translating I2C-bus/SMBus repeater that enables theprocessor low voltage 2-wire serial bus to interface with standard I2C-bus or SMBus I/O.While retaining all the operating modes and features of the I2C-bus system during thelevel shifts, it also permits extension of the I2C-bus by providing bidirectional buffering forboth the data (SDA) and the clock (SCL) lines, thus enabling the I2C-bus or SMBusmaximum capacitance of 400 pF on the higher voltage side. The SDA and SCL pins areover-voltage tolerant and are high-impedance when the PCA9519 is unpowered.
標簽: 4channel transla level 9519
上傳時間: 2013-11-19
上傳用戶:jisiwole