参数资料
型号: AT89S8253-24JI
厂商: Atmel
文件页数: 13/60页
文件大小: 0K
描述: IC 8051 MCU FLASH 12K 44PLCC
标准包装: 27
系列: 89S
核心处理器: 8051
芯体尺寸: 8-位
速度: 24MHz
连通性: SPI,UART/USART
外围设备: POR,WDT
输入/输出数: 32
程序存储器容量: 12KB(12K x 8)
程序存储器类型: 闪存
EEPROM 大小: 2K x 8
RAM 容量: 256 x 8
电压 - 电源 (Vcc/Vdd): 2.7 V ~ 5.5 V
振荡器型: 内部
工作温度: -40°C ~ 85°C
封装/外壳: 44-LCC(J 形引线)
包装: 管件
20
3286P–MICRO–3/10
AT89S8253
13. UART
The UART in the AT89S8253 operates the same way as the UART in the AT89S51 and
AT89S52. For more detailed information on the UART operation, please click on the document
link below:
13.1
Enhanced UART
In addition to all of its usual modes, the UART can perform framing error detection by looking for
missing stop bits, and automatic address recognition. The UART also fully supports multiproces-
sor communication as does the standard 80C51 UART.
When used for framing error detect, the UART looks for missing stop bits in the communication.
A missing bit will set the FE bit in the SCON register. The FE bit shares the SCON.7 bit with SM0
and the function of SCON.7 is determined by PCON.6 (SMOD0). If SMOD0 is set then SCON.7
functions as FE. SCON.7 functions as SM0 when SMOD0 is cleared. When used as FE,
SCON.7 can only be cleared by software.
13.1.1
Automatic Address Recognition
Automatic Address Recognition is a feature which allows the UART to recognize certain
addresses in the serial bit stream by using hardware to make the comparisons. This feature
saves a great deal of software overhead by eliminating the need for the software to examine
every serial address which passes by the serial port. This feature is enabled by setting the SM2
bit in SCON. In the 9-bit UART modes, mode 2 and mode 3, the Receive Interrupt flag (RI) will
be automatically set when the received byte contains either the “Given” address or the
“Broadcast” address. The 9-bit mode requires that the 9th information bit is a 1 to indicate that
the received information is an address and not data.
The 8-bit mode is called mode 1. In this mode the RI flag will be set if SM2 is enabled and the
information received has a valid stop bit following the 8 address bits and the information is either
a Given or Broadcast address.
Mode 0 is the Shift Register mode and SM2 is ignored.
Using the Automatic Address Recognition feature allows a master to selectively communicate
with one or more slaves by invoking the given slave address or addresses. All of the slaves may
be contacted by using the Broadcast address. Two special Function Registers are used to
define the slave’s address, SADDR, and the address mask, SADEN. SADEN is used to define
which bits in the SADDR are to be used and which bits are “don’t care”. The SADEN mask can
be logically ANDed with the SADDR to create the “Given” address which the master will use for
addressing each of the slaves. Use of the Given address allows multiple slaves to be recognized
while excluding others. The following examples will help to show the versatility of this scheme:
Slave 0
SADDR = 1100 0000
SADEN = 1111 1101
Given
= 1100 00X0
Slave 1
SADDR = 1100 0000
SADEN = 1111 1110
Given
= 1100 000X
相关PDF资料
PDF描述
AT89S8253-24JC IC 8051 MCU FLASH 12K 44PLCC
213931-2 CONN RCPT 34POS W/CABLE HARDWARE
213932-3 M-SERIES KIT,V.35,34P,UNASSM
AT89S8253-24AI IC 8051 MCU FLASH 12K 44TQFP
AT89S8253-24AC IC 8051 MCU FLASH 12K 44TQFP
相关代理商/技术参数
参数描述
AT89S8253-24JU 功能描述:8位微控制器 -MCU 12kB Flash 256B RAM 2.7V-5.5V RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
AT89S8253-24JU SL383 制造商:Atmel Corporation 功能描述:MCU 8-bit AT89 80C51 CISC 12KB Flash 3.3V/5V 44-Pin PLCC T/R
AT89S8253-24JU SL928 制造商:Atmel Corporation 功能描述:PLCC REVIS 'R' - Rail/Tube
AT89S8253-24JU@SL383 制造商:Adesto Technologies Corporation 功能描述:
AT89S8253-24PC 功能描述:8位微控制器 -MCU Microcontroller RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT