參數(shù)資料
型號: AT89S52-24AU
廠商: Atmel
文件頁數(shù): 7/37頁
文件大?。?/td> 0K
描述: IC MCU 8K FLASH 24MHZ 44-TQFP
產(chǎn)品培訓模塊: MCU Product Line Introduction
標準包裝: 160
系列: 89S
核心處理器: 8051
芯體尺寸: 8-位
速度: 24MHz
連通性: UART/USART
外圍設(shè)備: WDT
輸入/輸出數(shù): 32
程序存儲器容量: 8KB(8K x 8)
程序存儲器類型: 閃存
RAM 容量: 256 x 8
電壓 - 電源 (Vcc/Vdd): 4 V ~ 5.5 V
振蕩器型: 內(nèi)部
工作溫度: -40°C ~ 85°C
封裝/外殼: 44-TQFP
包裝: 托盤
產(chǎn)品目錄頁面: 616 (CN2011-ZH PDF)
15
1919D–MICRO–6/08
AT89S52
11. Baud Rate Generator
Timer 2 is selected as the baud rate generator by setting TCLK and/or RCLK in T2CON (Table
5-2). Note that the baud rates for transmit and receive can be different if Timer 2 is used for the
receiver or transmitter and Timer 1 is used for the other function. Setting RCLK and/or TCLK
puts Timer 2 into its baud rate generator mode, as shown in Figure 11-1.
The baud rate generator mode is similar to the auto-reload mode, in that a rollover in TH2
causes the Timer 2 registers to be reloaded with the 16-bit value in registers RCAP2H and
RCAP2L, which are preset by software.
The baud rates in Modes 1 and 3 are determined by Timer 2’s overflow rate according to the fol-
lowing equation.
The Timer can be configured for either timer or counter operation. In most applications, it is con-
figured for timer operation (CP/T2 = 0). The timer operation is different for Timer 2 when it is
used as a baud rate generator. Normally, as a timer, it increments every machine cycle (at 1/12
the oscillator frequency). As a baud rate generator, however, it increments every state time (at
1/2 the oscillator frequency). The baud rate formula is given below.
where (RCAP2H, RCAP2L) is the content of RCAP2H and RCAP2L taken as a 16-bit unsigned
integer.
Timer 2 as a baud rate generator is shown in Figure 11-1. This figure is valid only if RCLK or
TCLK = 1 in T2CON. Note that a rollover in TH2 does not set TF2 and will not generate an inter-
rupt. Note too, that if EXEN2 is set, a 1-to-0 transition in T2EX will set EXF2 but will not cause a
reload from (RCAP2H, RCAP2L) to (TH2, TL2). Thus, when Timer 2 is in use as a baud rate
generator, T2EX can be used as an extra external interrupt.
Note that when Timer 2 is running (TR2 = 1) as a timer in the baud rate generator mode, TH2 or
TL2 should not be read from or written to. Under these conditions, the Timer is incremented
every state time, and the results of a read or write may not be accurate. The RCAP2 registers
may be read but should not be written to, because a write might overlap a reload and cause
write and/or reload errors. The timer should be turned off (clear TR2) before accessing the Timer
2 or RCAP2 registers.
Modes 1 and 3 Baud Rates
Timer 2 Overflow Rate
16
------------------------------------------------------------
=
Modes 1 and 3
Baud Rate
---------------------------------------
Oscillator Frequency
32 x [65536-RCAP2H,RCAP2L)]
--------------------------------------------------------------------------------------
=
相關(guān)PDF資料
PDF描述
AT89S53-24JU MICRO CONTROLLER 44PLCC
AT89S8252-24PI MCU W/SPI 8KB FLSH 2K EEP 40-DIP
AT89S8253-24PI IC 8051 MCU FLASH 12K 40DIP
AT90CAN128-15AZ MCU AVR 128K FLASH 15MHZ 64TQFP
AT90CAN128-16MI IC MCU AVR FLASH 128K 64-QFN
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AT89S52-24AU SL383 制造商:Atmel Corporation 功能描述:8051 8K ISP FLASH 4.0 TO 5.5V
AT89S52-24AUR 功能描述:8051 89S Microcontroller IC 8-Bit 24MHz 8KB (8K x 8) FLASH 44-TQFP (10x10) 制造商:atmel 系列:89S 包裝:托盤 零件狀態(tài):有效 核心處理器:8051 核心尺寸:8-位 速度:24MHz 連接性:UART/USART 外設(shè):WDT I/O 數(shù):32 程序存儲容量:8KB(8K x 8) 程序存儲器類型:閃存 EEPROM 容量:- RAM 容量:256 x 8 電壓 - 電源(Vcc/Vdd):4 V ~ 5.5 V 數(shù)據(jù)轉(zhuǎn)換器:- 振蕩器類型:內(nèi)部 工作溫度:-40°C ~ 85°C(TA) 封裝/外殼:44-TQFP 供應(yīng)商器件封裝:44-TQFP(10x10) 標準包裝:160
AT89S52-24JC 功能描述:8位微控制器 -MCU 8K ISP FLASH 2.7 TO 5.5V - 24MHZ 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 最大時鐘頻率:50 MHz 程序存儲器大小: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 安裝風格:SMD/SMT
AT89S52-24JI 功能描述:8位微控制器 -MCU 8K ISP FLASH 2.7 TO 5.5V - 24MHz 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 最大時鐘頻率:50 MHz 程序存儲器大小: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 安裝風格:SMD/SMT
AT89S52-24JISL383 制造商:Atmel Corporation 功能描述:MCU 8-bit AT89 80C51 CISC 8KB Flash 5V 44-Pin PLCC T/R