]本文介紹了如何利用CPLD(復雜可編程邏輯器件)與單片機的結合實現(xiàn)并行I/\r\nO(輸入/輸出)接口的擴展。該設計與用8255做并行I/O接口相比,與單片機軟件完全兼容,\r\n同時擁有速度快,功耗低,價格便宜,使用靈活等特點
上傳時間: 2013-08-14
上傳用戶:xa_lgy
The PCA9534 is a 16-pin CMOS device that provide 8 bits of General Purpose parallel Input/Output (GPIO) expansion for I2C-bus/SMBus applications and was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders. The improvements include higher drive capability, 5 V I/O tolerance, lower supply current, individual I/O configuration, 400 kHz clock frequency, and smaller packaging. I/O expanders provide a simple solution when additional I/O is needed for ACPI power switches, sensors, push buttons, LEDs, fans, etc.
上傳時間: 2013-10-10
上傳用戶:inwins
The PCA9535 and PCA9535C are 24-pin CMOS devices that provide 16 bits of GeneralPurpose parallel Input/Output (GPIO) expansion for I2C-bus/SMBus applications and wasdeveloped to enhance the NXP Semiconductors family of I2C-bus I/O expanders. Theimprovements include higher drive capability, 5 V I/O tolerance, lower supply current,individual I/O configuration, and smaller packaging. I/O expanders provide a simplesolution when additional I/O is needed for ACPI power switches, sensors, push buttons,LEDs, fans, etc.
上傳時間: 2013-10-21
上傳用戶:愛死愛死
The PCA9536 is an 8-pin CMOS device that provides 4 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. I/O expanders providea simple solution when additional I/O is needed for ACPI power switches, sensors,push buttons, LEDs, fans, etc.
上傳時間: 2013-10-09
上傳用戶:731140412
The PCA9537 is a 10-pin CMOS device that provides 4 bits of General Purpose parallelInput/Output (GPIO) expansion with interrupt and reset for I2C-bus/SMBus applicationsand was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders.I/O expanders provide a simple solution when additional I/O is needed for ACPI powerswitches, sensors, push-buttons, LEDs, fans, etc.
上傳時間: 2013-10-14
上傳用戶:wuchunzhong
The PCA9538 is a 16-pin CMOS device that provides 8 bits of General Purpose parallelInput/Output (GPIO) expansion with interrupt and reset for I2C-bus/SMBus applicationsand was developed to enhance the NXP Semiconductors family of I2C-bus I/O expanders.I/O expanders provide a simple solution when additional I/O is needed for ACPI powerswitches, sensors, push-buttons, LEDs, fans, etc.
上傳時間: 2014-01-24
上傳用戶:youmo81
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.
上傳時間: 2013-11-13
上傳用戶:fredguo
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.
上傳時間: 2014-01-18
上傳用戶:bs2005
8051單片機系統(tǒng)擴展與接口技術:第一節(jié) 8051 單片機系統(tǒng)擴展概述第二節(jié) 單片機外部存儲器擴展第三節(jié) 單片機輸入輸出(I/O)口擴展及應用第四節(jié) LED顯示器接口電路及顯示程序第五節(jié) 單片機鍵盤接口技術第六節(jié) 單片機與數(shù)模(D/A)及模數(shù)(A/D)轉(zhuǎn)換1、地址總線(Address Bus,簡寫為AB)地址總線可傳送單片機送出的地址信號,用于訪問外部存儲器單元或I/O端口。A 地址總線是單向的,地址信號只是由單片機向外發(fā)出。B 地址總線的數(shù)目決定了可直接訪問的存儲器單元的數(shù)目。例如N位地址,可以產(chǎn)生2N個連續(xù)地址編碼,因此可訪問2N個存儲單元,即通常所說的尋址范圍為 2N個地址單元。MCS—51單片機有十六位地址線,因此存儲器展范圍可達216 = 64KB地址單元。C 掛在總線上的器件,只有地址被選中的單元才能與CPU交換數(shù)據(jù),其余的都暫時不能操作,否則會引起數(shù)據(jù)沖突。2、數(shù)據(jù)總線(Data Bus,簡寫為DB)數(shù)據(jù)總線用于在單片機與存儲器之間或單片機與I/O端口之間傳送數(shù)據(jù)。A 單片機系統(tǒng)數(shù)據(jù)總線的位數(shù)與單片機處理數(shù)據(jù)的字長一致。例如MCS—51單片機是8位字長,所以數(shù)據(jù)總線的位數(shù)也是8位。B 數(shù)據(jù)總線是雙向的,即可以進行兩個方向的數(shù)據(jù)傳送。3、控制總線(Control Bus,簡寫為CB)控制總線實際上就是一組控制信號線,包括單片機發(fā)出的,以及從其它部件送給單片機的各種控制或聯(lián)絡信號。對于一條控制信號線來說,其傳送方向是單向的,但是由不同方向的控制信號線組合的控制總線則表示為雙向的。總線結構形式大大減少了單片機系統(tǒng)中連接線的數(shù)目,提高了系統(tǒng)的可靠性,增加了系統(tǒng)的靈活性。此外,總線結構也使擴展易于實現(xiàn),各功能部件只要符合總線規(guī)范,就可以很方便地接入系統(tǒng),實現(xiàn)單片機擴展。
標簽: 8051 單片機 系統(tǒng)擴展 接口技術
上傳時間: 2013-10-18
上傳用戶:assef
CANWiFi-600/622是為電信級應用而設計的工業(yè)級CAN轉(zhuǎn)WiFi接口卡/設配器,它內(nèi)部集成了一路/兩路CAN-bus 接口、一個以太網(wǎng)接口、一路無線WIFI接口以及TCP/IP 協(xié)議棧,符合 IEEE802.11b/g/n 標準,具有傳輸速率高、接收靈敏度高和傳輸距離遠等特點,CANWIFI-600/622通過與 WiFi 基站設備(或無線寬帶路由器或無線AP)一起配合使用,設備可以在與其它擁有相同網(wǎng)絡ID的接入點間自由的漫游,通過無線WiFi把CAN網(wǎng)絡接入Wireless Ethernet。用戶利于它可以輕松完成CAN-bus 網(wǎng)絡和Wireless Ethernet的互連互通,進一步拓展CAN-bus 網(wǎng)絡的范圍。
上傳時間: 2015-01-02
上傳用戶:cooran