參數(shù)資料
型號(hào): AT89LP4052-16PI
廠商: Atmel
文件頁數(shù): 25/94頁
文件大?。?/td> 0K
描述: IC 8051 MCU FLASH 4K 20DIP
標(biāo)準(zhǔn)包裝: 18
系列: 89LP
核心處理器: 8051
芯體尺寸: 8-位
速度: 16MHz
連通性: SPI,UART/USART
外圍設(shè)備: 欠壓檢測(cè)/復(fù)位,POR,PWM,WDT
輸入/輸出數(shù): 15
程序存儲(chǔ)器容量: 4KB(4K x 8)
程序存儲(chǔ)器類型: 閃存
RAM 容量: 256 x 8
電壓 - 電源 (Vcc/Vdd): 2.4 V ~ 5.5 V
振蕩器型: 內(nèi)部
工作溫度: -40°C ~ 85°C
封裝/外殼: 20-DIP(0.300",7.62mm)
包裝: 管件
其它名稱: AT89LP4052-20PI
AT89LP4052-20PI-ND
31
3547J–MICRO–10/09
AT89LP2052/LP4052
and a low in the next cycle, interrupt request flag IEx in TCON is set. Flag bit IEx then requests
the interrupt. Since the external interrupt pins are sampled once each clock cycle, an input high
or low should hold for at least 2 oscillator periods to ensure sampling. If the external interrupt is
transition-activated, the external source has to hold the request pin high for at least two clock
cycles, and then hold it low for at least two clock cycles to ensure that the transition is seen so
that interrupt request flag IEx will be set. IEx will be automatically cleared by the CPU when the
service routine is called if generated in edge-triggered mode. If the external interrupt is level-acti-
vated, the external source has to hold the request active until the requested interrupt is actually
generated. Then the external source must deactivate the request before the interrupt service
routine is completed, or else another interrupt will be generated.
18. Serial Interface
The serial port is full-duplex, which means it can transmit and receive simultaneously. It is also
receive-buffered, which means it can begin receiving a second byte before a previously received
byte has been read from the receive register. (However, if the first byte still has not been read
when reception of the second byte is complete, the first byte will be lost.) The serial port receive
and transmit registers are both accessed at Special Function Register SBUF. Writing to SBUF
loads the transmit register, and reading SBUF accesses a physically separate receive register.
The serial port can operate in the following four modes.
Mode 0: Half-Duplex serial data enters or exits through RXD. TXD outputs the shift clock. Eight
data bits are transmitted/received, with the LSB first. The baud rate is fixed at 1/2 the oscillator
frequency.
Mode 1: 10 bits are transmitted (through TXD) or received (through RXD): a start bit (0), 8 data
bits (LSB first), and a stop bit (1). On receive, the stop bit goes into RB8 in Special Function
Register SCON. The baud rate is variable based on Timer 1 overflow.
Mode 2: 11 bits are transmitted (through TXD) or received (through RXD): a start bit (0), 8 data
bits (LSB first), a programmable ninth data bit, and a stop bit (1). On transmit, the 9th data bit
(TB8 in SCON) can be assigned the value of “0” or “1”. For example, the parity bit (P, in the
PSW) can be moved into TB8. On receive, the 9th data bit goes into RB8 in Special Function
Register SCON, while the stop bit is ignored. The baud rate is programmable to either 1/16 or
1/32 the oscillator frequency.
Mode 3: 11 bits are transmitted (through TXD) or received (through RXD): a start bit (0), 8 data
bits (LSB first), a programmable ninth data bit, and a stop bit (1). In fact, Mode 3 is the same as
Mode 2 in all respects except the baud rate, which in Mode 3 is variable based on Timer 1
overflow.
In all four modes, transmission is initiated by any instruction that uses SBUF as a destination
register. Reception is initiated in Mode 0 by the condition RI = 0 and REN = 1. Reception is initi-
ated in the other modes by the incoming start bit if REN = 1.
18.1
Multiprocessor Communications
Modes 2 and 3 have a special provision for multiprocessor communications. In these modes, 9
data bits are received, followed by a stop bit. The ninth bit goes into RB8. Then comes a stop bit.
The port can be programmed such that when the stop bit is received, the serial port interrupt is
activated only if RB8 = 1. This feature is enabled by setting bit SM2 in SCON.
The following example shows how to use the serial interrupt for multiprocessor communications.
When the master processor must transmit a block of data to one of several slaves, it first sends
相關(guān)PDF資料
PDF描述
DSPIC30F3011-30I/P IC DSPIC MCU/DSP 24K 40DIP
PIC16LF873A-I/SP IC MCU FLASH 4KX14 EE A/D 28DIP
AT89C51AC3-RLTIM IC 8051 MCU FLASH 64K 44VQFP
PIC16LF873A-I/SO IC MCU FLASH 4KX14 EE A/D 28SOIC
AT89C51AC3-RDTIM IC 8051 MCU FLASH 64K 64VQFP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AT89LP4052-16PU 功能描述:8位微控制器 -MCU Microcontroller RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
AT89LP4052-16SI 功能描述:8位微控制器 -MCU Microcontroller RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
AT89LP4052-16SU 功能描述:IC 8051 MCU FLASH 4K 20SOIC RoHS:是 類別:集成電路 (IC) >> 嵌入式 - 微控制器, 系列:89LP 標(biāo)準(zhǔn)包裝:1,500 系列:AVR® ATtiny 核心處理器:AVR 芯體尺寸:8-位 速度:16MHz 連通性:I²C,LIN,SPI,UART/USART,USI 外圍設(shè)備:欠壓檢測(cè)/復(fù)位,POR,PWM,溫度傳感器,WDT 輸入/輸出數(shù):16 程序存儲(chǔ)器容量:8KB(4K x 16) 程序存儲(chǔ)器類型:閃存 EEPROM 大小:512 x 8 RAM 容量:512 x 8 電壓 - 電源 (Vcc/Vdd):2.7 V ~ 5.5 V 數(shù)據(jù)轉(zhuǎn)換器:A/D 11x10b 振蕩器型:內(nèi)部 工作溫度:-40°C ~ 125°C 封裝/外殼:20-SOIC(0.295",7.50mm 寬) 包裝:帶卷 (TR)
AT89LP4052-16XI 功能描述:8位微控制器 -MCU Microcontroller RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
AT89LP4052-16XU 功能描述:8位微控制器 -MCU Microcontroller RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT