參數(shù)資料
型號(hào): ATMEGA1284-MU
廠商: Atmel
文件頁數(shù): 133/160頁
文件大小: 0K
描述: IC MCU AVR 128K FLASH 44QFN
產(chǎn)品培訓(xùn)模塊: MCU Product Line Introduction
megaAVR Introduction
標(biāo)準(zhǔn)包裝: 416
系列: AVR® ATmega
核心處理器: AVR
芯體尺寸: 8-位
速度: 20MHz
連通性: I²C,SPI,UART/USART
外圍設(shè)備: 欠壓檢測/復(fù)位,POR,PWM,WDT
輸入/輸出數(shù): 32
程序存儲(chǔ)器容量: 128KB(64K x 16)
程序存儲(chǔ)器類型: 閃存
EEPROM 大?。?/td> 4K x 8
RAM 容量: 16K x 8
電壓 - 電源 (Vcc/Vdd): 1.8 V ~ 5.5 V
數(shù)據(jù)轉(zhuǎn)換器: A/D 8x10b
振蕩器型: 內(nèi)部
工作溫度: -40°C ~ 85°C
封裝/外殼: 44-VFQFN 裸露焊盤
包裝: 托盤
74
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
If PORTxn is written logic one when the pin is configured as an output pin, the port pin is driven
high (one). If PORTxn is written logic zero when the pin is configured as an output pin, the port
pin is driven low (zero).
14.2.2
Toggling the pin
Writing a logic one to PINxn toggles the value of PORTxn, independent on the value of DDRxn.
Note that the SBI instruction can be used to toggle one single bit in a port.
14.2.3
Switching between input and output
When switching between tri-state ({DDxn, PORTxn} = 0b00) and output high ({DDxn, PORTxn}
= 0b11), an intermediate state with either pull-up enabled {DDxn, PORTxn} = 0b01) or output
low ({DDxn, PORTxn} = 0b10) must occur. Normally, the pull-up enabled state is fully accept-
able, as a high-impedant environment will not notice the difference between a strong high driver
and a pull-up. If this is not the case, the PUD bit in the MCUCR Register can be set to disable all
pull-ups in all ports.
Switching between input with pull-up and output low generates the same problem. The user
must use either the tri-state ({DDxn, PORTxn} = 0b00) or the output high state ({DDxn, PORTxn}
= 0b11) as an intermediate step.
Table 14-1 summarizes the control signals for the pin value.
14.2.4
Reading the Pin Value
Independent of the setting of Data Direction bit DDxn, the port pin can be read through the
PINxn Register bit. As shown in Figure 14-2, the PINxn Register bit and the preceding latch con-
stitute a synchronizer. This is needed to avoid metastability if the physical pin changes value
near the edge of the internal clock, but it also introduces a delay. Figure 14-3 shows a timing dia-
gram of the synchronization when reading an externally applied pin value. The maximum and
minimum propagation delays are denoted t
pd,max and tpd,min respectively.
Table 14-1.
Port pin configurations.
DDxn
PORTxn
PUD
(in MCUCR)
I/O
Pull-up
Comment
0
X
Input
No
Tri-state (Hi-Z)
0
1
0
Input
Yes
Pxn will source current if ext. pulled low.
0
1
Input
No
Tri-state (Hi-Z)
1
0
X
Output
No
Output Low (Sink)
1
X
Output
No
Output High (Source)
相關(guān)PDF資料
PDF描述
ATSAM3U2EA-AU IC MCU 32BIT 128KB FLASH 144LQFP
AT91SAM7SE32-CU MCU ARM 32K HS FLASH 144-LFBGA
1-1761184-2 CONN PLUG 6POS SDL AU FLAT
5-1761185-6 CONN RCPT 16POS R/A SDL PCB GOLD
5-1761199-3 CONN RCPT 8POS RT ANG PCB
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ATMEGA1284-MUR 功能描述:8位微控制器 -MCU AVR 128KB FLSH 4KB EE16KB SRAM-20 MHz 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
ATMEGA1284P 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:8-bit Atmel Microcontroller with 16/32/64/128K Bytes In-System Programmable Flash
ATMEGA1284P_09 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:8-bit Microcontroller with 128K Bytes In-System Programmable Flash
ATMEGA1284P_1 制造商:ATMEL 制造商全稱:ATMEL Corporation 功能描述:8-bit Microcontroller with 128K Bytes In-System Programmable Flash
ATMEGA1284P-AU 功能描述:8位微控制器 -MCU 128KB Flash 20MHz 1.8V-5.5V 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