參數資料
型號: ATmega8535
廠商: Atmel Corp.
元件分類: 8位微控制器
英文描述: -bit AVR Microcontroller with 8K Bytes In- System Programmable Flash
中文描述: 位AVR微控制器具有8K字節(jié)的系統(tǒng)內可編程閃存
文件頁數: 55/152頁
文件大?。?/td> 2528K
代理商: ATMEGA8535
148
2486AA–AVR–02/2013
ATmega8(L)
USART Register
Description
USART I/O Data
Register – UDR
The USART Transmit Data Buffer Register and USART Receive Data Buffer Registers share the
same I/O address referred to as USART Data Register or UDR. The Transmit Data Buffer Reg-
ister (TXB) will be the destination for data written to the UDR Register location. Reading the
UDR Register location will return the contents of the Receive Data Buffer Register (RXB).
For 5-bit, 6-bit, or 7-bit characters the upper unused bits will be ignored by the Transmitter and
set to zero by the Receiver.
The transmit buffer can only be written when the UDRE Flag in the UCSRA Register is set. Data
written to UDR when the UDRE Flag is not set, will be ignored by the USART Transmitter. When
data is written to the transmit buffer, and the Transmitter is enabled, the Transmitter will load the
data into the Transmit Shift Register when the Shift Register is empty. Then the data will be seri-
ally transmitted on the TxD pin.
The receive buffer consists of a two level FIFO. The FIFO will change its state whenever the
receive buffer is accessed. Due to this behavior of the receive buffer, do not use Read-Modify-
Write instructions (SBI and CBI) on this location. Be careful when using bit test instructions
(SBIC and SBIS), since these also will change the state of the FIFO.
USART Control and
Status Register A –
UCSRA
Bit 7 – RXC: USART Receive Complete
This flag bit is set when there are unread data in the receive buffer and cleared when the receive
buffer is empty (that is, does not contain any unread data). If the Receiver is disabled, the
receive buffer will be flushed and consequently the RXC bit will become zero. The RXC Flag can
be used to generate a Receive Complete interrupt (see description of the “Bit 7 – RXCIE: RX
Bit 6 – TXC: USART Transmit Complete
This flag bit is set when the entire frame in the Transmit Shift Register has been shifted out and
there are no new data currently present in the transmit buffer (UDR). The TXC Flag bit is auto-
matically cleared when a transmit complete interrupt is executed, or it can be cleared by writing
a one to its bit location. The TXC Flag can generate a Transmit Complete interrupt (see descrip-
Bit 5 – UDRE: USART Data Register Empty
The UDRE Flag indicates if the transmit buffer (UDR) is ready to receive new data. If UDRE is
one, the buffer is empty, and therefore ready to be written. The UDRE Flag can generate a Data
Register Empty interrupt (see description of the “Bit 5 – UDRIE: USART Data Register Empty
UDRE is set after a reset to indicate that the Transmitter is ready.
Bit
76543210
RXB[7:0]
UDR (Read)
TXB[7:0]
UDR (Write)
Read/Write
R/W
Initial Value
00000000
Bit
765
4321
0
RXC
TXC
UDRE
FE
DOR
PE
U2X
MPCM
UCSRA
Read/Write
R
R/W
R
R/W
Initial Value
001
0000
0
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相關代理商/技術參數
參數描述
ATmega8535-16AC 功能描述:8位微控制器 -MCU AVR 8K FLASH 512B SRAM 512B EE RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數據總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數據 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
ATMEGA8535-16AI 功能描述:8位微控制器 -MCU AVR 8K FLASH 512B SRAM 512B EE RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數據總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數據 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
ATMEGA8535-16AJ 功能描述:IC MCU AVR 8K 5V 16MHZ 44-TQFP RoHS:是 類別:集成電路 (IC) >> 嵌入式 - 微控制器, 系列:AVR® ATmega 標準包裝:9 系列:87C 核心處理器:8051 芯體尺寸:8-位 速度:40/20MHz 連通性:UART/USART 外圍設備:POR,WDT 輸入/輸出數:32 程序存儲器容量:32KB(32K x 8) 程序存儲器類型:OTP EEPROM 大小:- RAM 容量:256 x 8 電壓 - 電源 (Vcc/Vdd):4.5 V ~ 5.5 V 數據轉換器:- 振蕩器型:內部 工作溫度:0°C ~ 70°C 封裝/外殼:40-DIP(0.600",15.24mm) 包裝:管件
ATmega8535-16AU 功能描述:8位微控制器 -MCU 8kB Flash 0.5kB EEPROM 32 I/O Pins RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數據總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數據 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
ATMEGA8535-16AUR 功能描述:8位微控制器 -MCU AVR 8K FLSH 544B SRAM 512B EE-16MHz RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數據總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數據 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