- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄1948 > MC68711E20VFNE2 (Freescale Semiconductor)IC MCU 8BIT 52-PLCC PDF資料下載
參數(shù)資料
| 型號： | MC68711E20VFNE2 |
| 廠商： | Freescale Semiconductor |
| 文件頁數(shù)： | 104/138頁 |
| 文件大小： | 0K |
| 描述： | IC MCU 8BIT 52-PLCC |
| 標準包裝： | 23 |
| 系列： | HC11 |
| 核心處理器： | HC11 |
| 芯體尺寸： | 8-位 |
| 速度： | 4MHz |
| 連通性： | SCI，SPI |
| 外圍設(shè)備： | POR，WDT |
| 輸入/輸出數(shù)： | 38 |
| 程序存儲器容量： | 20KB（20K x 8） |
| 程序存儲器類型： | OTP |
| EEPROM 大?。?/td> | 512 x 8 |
| RAM 容量： | 768 x 8 |
| 電壓 - 電源 (Vcc/Vdd)： | 4.5 V ~ 5.5 V |
| 數(shù)據(jù)轉(zhuǎn)換器： | A/D 8x8b |
| 振蕩器型： | 內(nèi)部 |
| 工作溫度： | -40°C ~ 105°C |
| 封裝/外殼： | 52-LCC（J 形引線） |
| 包裝： | 管件 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁第67頁第68頁第69頁第70頁第71頁第72頁第73頁第74頁第75頁第76頁第77頁第78頁第79頁第80頁第81頁第82頁第83頁第84頁第85頁第86頁第87頁第88頁第89頁第90頁第91頁第92頁第93頁第94頁第95頁第96頁第97頁第98頁第99頁第100頁第101頁第102頁第103頁當(dāng)前第104頁第105頁第106頁第107頁第108頁第109頁第110頁第111頁第112頁第113頁第114頁第115頁第116頁第117頁第118頁第119頁第120頁第121頁第122頁第123頁第124頁第125頁第126頁第127頁第128頁第129頁第130頁第131頁第132頁第133頁第134頁第135頁第136頁第137頁第138頁
Serial Communications Interface (SCI)
MC68HC711D3 Data Sheet, Rev. 2.1
68
Freescale Semiconductor
6.5 Wakeup Feature
The wakeup feature reduces SCI service overhead in multiple receiver systems. Software for each
receiver evaluates the first character of each message. The receiver is placed in wakeup mode by writing
a 1 to the RWU bit in the SCCR2 register. While RWU is 1, all of the receiver-related status flags (RDRF,
IDLE, OR, NF, and FE) are inhibited (cannot become set). Although RWU can be cleared by a software
write to SCCR2, to do so would be unusual. Normally, RWU is set by software and is cleared
automatically with hardware. Whenever a new message begins, logic alerts the sleeping receivers to
wake up and evaluate the initial character of the new message.
Two methods of wakeup are available:
Idle line wakeup
Address mark wakeup
During idle line wakeup, a sleeping receiver awakens as soon as the RxD line becomes idle. In the
address mark wakeup, logic 1 in the most significant bit (MSB) of a character wakes up all sleeping
receivers.
6.5.1 Idle-Line Wakeup
To use the receiver wakeup method, establish a software addressing scheme to allow the transmitting
devices to direct a message to individual receivers or to groups of receivers. This addressing scheme can
take any form as long as all transmitting and receiving devices are programmed to understand the same
scheme. Because the addressing information is usually the first frame(s) in a message, receivers that are
not part of the current task do not become burdened with the entire set of addressing frames. All receivers
are awake (RWU = 0) when each message begins. As soon as a receiver determines that the message
is not intended for it, software sets the RWU bit (RWU = 1), which inhibits further flag setting until the RxD
line goes idle at the end of the message. As soon as an idle line is detected by receiver logic, hardware
automatically clears the RWU bit so that the first frame of the next message can be received. This type
of receiver wakeup requires a minimum of one idle-line frame time between messages and no idle time
between frames in a message.
6.5.2 Address-Mark Wakeup
The serial characters in this type of wakeup consist of seven (eight if M = 1) information bits and an MSB,
which indicates an address character (when set to 1 — mark). The first character of each message is an
addressing character (MSB = 1). All receivers in the system evaluate this character to determine if the
remainder of the message is directed toward this particular receiver. As soon as a receiver determines
that a message is not intended for it, the receiver activates the RWU function by using a software write to
set the RWU bit. Because setting RWU inhibits receiver-related flags, there is no further software
overhead for the rest of this message. When the next message begins, its first character has its MSB set,
which automatically clears the RWU bit and enables normal character reception. The first character
whose MSB is set is also the first character to be received after wakeup because RWU gets cleared
before the stop bit for that frame is serially received. This type of wakeup allows messages to include gaps
of idle time, unlike the idle-line method, but there is a loss of efficiency because of the extra bit time for
each character (address bit) required for all characters.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MC68882RC50A | IC COPROCESSOR FLOAT PT 68-PGA |
| MC68908GR16CFJE | IC MCU 16K FLASH 8MHZ SPI 32LQFP |
| MC68E360ZQ25VLR2 | IC MPU QUICC 32BIT 357-PBGA |
| MC68EC000EI8R2 | IC MPU 32BIT 85MHZ 68-PLCC |
| MC68EC030FE25CB1 | IC MPU 32BIT ENH 25MHZ 132-CQFP |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MC6875 | 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:CLOCK GENERATOR/DRIVER (SCHOTTKY MONOLITHIC INTEGRATED CIRCUIT) |
| MC6875A | 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:CLOCK GENERATOR/DRIVER (SCHOTTKY MONOLITHIC INTEGRATED CIRCUIT) |
| MC6875AL | 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:CLOCK GENERATOR/DRIVER (SCHOTTKY MONOLITHIC INTEGRATED CIRCUIT) |
| MC6875L | 制造商:MOTOROLA 功能描述:IC |
| MC688 | 制造商:未知廠家 制造商全稱:未知廠家 功能描述:INTEGRATED CIRCUITS |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。