参数资料
型号: AT89S4051-24PU
厂商: ATMEL CORP
元件分类: 微控制器/微处理器
英文描述: 8-bit Microcontroller with 2K/4K Bytes Flash
中文描述: 8-BIT, FLASH, 24 MHz, MICROCONTROLLER, PDIP20
封装: 0.300 INCH, GREEN, MS-001AD, PLASTIC, DIP-20
文件页数: 16/45页
文件大小: 981K
代理商: AT89S4051-24PU
16
3390C–MICRO–7/05
AT89S2051/S4051
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
In the previous example SADDR is the same and the SADEN data is used to differentiate
between the two slaves. Slave 0 requires a 0 in bit 0 and it ignores bit 1. Slave 1 requires a 0 in
bit 1 and bit 0 is ignored. A unique address for slave 0 would be 1100 0010 since slave 1
requires a 0 in bit 1. A unique address for slave 1 would be 1100 0001 since a 1 in bit 0 will
exclude slave 0. Both slaves can be selected at the same time by an address which has bit 0 = 0
(for slave 0) and bit 1 = 0 (for slave 1). Thus, both could be addressed with 1100 0000.
In a more complex system the following could be used to select slaves 1 and 2 while excluding
slave 0:
Slave 0
SADDR = 1100 0000
SADEN = 1111 1001
Given
= 1100 0XX0
Slave 1
SADDR = 1110 0000
SADEN = 1111 1010
Given
= 1110 0X0X
Slave 2
SADDR = 1110 0000
SADEN = 1111 1100
Given
= 1110 00XX
In the above example the differentiation among the 3 slaves is in the lower 3 address bits. Slave
0 requires that bit 0 = 0 and it can be uniquely addressed by 1110 0110. Slave 1 requires that bit
1 = 0 and it can be uniquely addressed by 1110 and 0101. Slave 2 requires that bit 2 = 0 and its
unique address is 1110 0011. To select Slaves 0 and 1 and exclude Slave 2, use address 1110
0100, since it is necessary to make bit 2 = 1 to exclude slave 2.
The Broadcast Address for each slave is created by taking the logical OR of SADDR and
SADEN. Zeros in this result are trended as don’t cares. In most cases, interpreting the don’t
cares as ones, the broadcast address will be FF hexadecimal.
Upon reset SADDR (SFR address 0A9H) and SADEN (SFR address 0B9H) are loaded with 0s.
This produces a given address of all “don’t cares” as well as a Broadcast address of all “don’t
cares”. This effectively disables the Automatic Addressing mode and allows the microcontroller
to use standard 80C51-type UART drivers which do not make use of this feature.
相关PDF资料
PDF描述
AT89S4051-24SC 8-bit Microcontroller with 2K/4K Bytes Flash
AT89S4051-24SI 8-bit Microcontroller with 2K/4K Bytes Flash
AT89S4051-24SU 8-bit Microcontroller with 2K/4K Bytes Flash
AT89S4D12 8-Bit Microcontroller with 132K Bytes Flash Data Memory
AT89S4D12-12JC 8-Bit Microcontroller with 132K Bytes Flash Data Memory
相关代理商/技术参数
参数描述
AT89S4051-24SU 功能描述:8位微控制器 -MCU 4K FLASH 24MHZ 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
AT89S4051-24SUR 功能描述:8051 89S Microcontroller IC 8-Bit 24MHz 4KB (4K x 8) FLASH 20-SOIC 制造商:atmel 系列:89S 包装:管件 零件状态:有效 核心处理器:8051 核心尺寸:8-位 速度:24MHz 连接性:UART/USART 外设:欠压检测/复位,POR,PWM I/O 数:15 程序存储容量:4KB(4K x 8) 程序存储器类型:闪存 EEPROM 容量:- RAM 容量:256 x 8 电压 - 电源(Vcc/Vdd):2.7 V ~ 5.5 V 数据转换器:- 振荡器类型:内部 工作温度:-40°C ~ 85°C(TA) 封装/外壳:20-SOIC(0.295",7.50mm 宽) 供应商器件封装:20-SOIC 标准包装:37
AT89S4D12-12RC 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
AT89S4D12-12RI 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
AT89S51-24AC 功能描述:8位微控制器 -MCU 4K ISP FLASH 2.7 TO 5.5V - 24 MHZ 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