參數(shù)資料
型號: AT89LV55-12AI
廠商: Atmel
文件頁數(shù): 9/32頁
文件大?。?/td> 0K
描述: IC 8051 MCU FLASH 20K 44TQFP
標(biāo)準(zhǔn)包裝: 160
系列: 89LV
核心處理器: 8051
芯體尺寸: 8-位
速度: 12MHz
連通性: UART/USART
輸入/輸出數(shù): 32
程序存儲器容量: 20KB(20K x 8)
程序存儲器類型: 閃存
RAM 容量: 256 x 8
電壓 - 電源 (Vcc/Vdd): 2.7 V ~ 6 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
17
0811E–MICRO–9/08
AT89LV55
16. Program Memory Lock Bits
The AT89LV55 has three lock bits that can be left unprogrammed (U) or can be programmed (P)
to obtain the additional features listed in Table 16-1:
When lock bit 1 is programmed, the logic level at the EA pin is sampled and latched during reset.
If the device is powered up without a reset, the latch initializes to a random value and holds that
value until reset is activated. The latched value of EA must agree with the current logic level at
that pin in order for the device to function properly.
The AT89LV55 code memory array is programmed byte-by-byte. To program any non-blank
byte in the on-chip Flash Memory, the entire memory must be erased using the Chip
Erase Mode.
17. Programming the Flash
The AT89LV55 is normally shipped with the on-chip Flash memory array in the erased state
(that is, contents = FFH) and ready to be programmed.
Programming Algorithm: Before programming the AT89LV55, the address, data and control
signals should be set up according to Table 18-1, “Flash Programming Modes,” on page 19 and
Figure 18-1. To program the AT89LV55, take the following steps:
1.
Input the desired memory location on the address lines.
2.
Input the appropriate data byte on the data lines.
3.
Activate the correct combination of control signals.
4.
Raise EA/V
PP to 12V
5.
Pulse ALE/PROG once to program a byte in the Flash array or the lock bits. The byte-
write cycle is self-timed and typically takes no more than 1.5 ms. Repeat steps 1
through 5, changing the address and data for the entire array or until the end of the
object file is reached.
Data Polling: The AT89LV55 features Data Polling to indicate the end of a write cycle. During a
write cycle, an attempted read of the last byte written will result in the complement of the written
data on PO.7. Once the write cycle has been completed, true data is valid on all outputs, and the
next cycle may begin. Data Polling may begin any time after a write cycle has been initiated.
Ready/Busy: The progress of byte programming can also be monitored by the RDY/BUSY out-
put signal. P3.4 is pulled low after ALE goes high during programming to indicate BUSY. P3.4 is
pulled high again when programming is done to indicate READY.
Table 16-1.
Lock Bit Protection Modes
Program Lock Bits
LB1
LB2
LB3
Protection Type
1
U
No program lock features.
2P
U
MOVC instructions executed from external program memory are
disabled from fetching code bytes from internal memory, EA is
sampled and latched on reset, and further programming of the
Flash memory is disabled.
3
P
U
Same as mode 2, but verify is also disabled.
4
P
Same as mode 3, but external execution is also disabled.
相關(guān)PDF資料
PDF描述
AT89LV55-12AC IC 8051 MCU FLASH 20K 44TQFP
AT91RM9200-CI-002 IC ARM9 MCU 256 BGA
AT91RM9200-QI-002 IC ARM9 MCU 208 PQFP
PIC18F4450-I/P IC PIC MCU FLASH 8KX16 40DIP
PIC16C715-20/SO IC MCU OTP 2KX14 A/D 18SOIC
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AT89LV55-12AU 功能描述:8位微控制器 -MCU 16K FLASH 8051 MCU - 16K FLASH 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(fēng)格:SMD/SMT
AT89LV5512JC 制造商:Atmel Corporation 功能描述:MCU 8-bit AT89 80C51 CISC 20KB Flash 3.3V/5V 44-Pin PLCC
AT89LV55-12JC 功能描述:8位微控制器 -MCU 80C31 w/8k 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(fēng)格:SMD/SMT
AT89LV55-12JI 功能描述:8位微控制器 -MCU 80C31 w/8k 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(fēng)格:SMD/SMT
AT89LV55-12JU 功能描述:8位微控制器 -MCU 16K FLASH 8051 MCU - 12MHZ 2.4V-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(fēng)格:SMD/SMT