参数资料
型号: AT87C54X2-RLTUL
厂商: Atmel
文件页数: 31/62页
文件大小: 0K
描述: IC 8051 MCU 16K EPROM 44VQFP
标准包装: 800
系列: 87C
核心处理器: 8051
芯体尺寸: 8-位
速度: 30/20MHz
连通性: UART/USART
外围设备: POR,WDT
输入/输出数: 32
程序存储器容量: 16KB(16K x 8)
程序存储器类型: OTP
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-LQFP
包装: 托盘
37
4431E–8051–04/06
AT/TS8xC54/8X2
17. TS87C54/58X2 EPROM
17.1
EPROM Structure
The TS87C54/58X2 EPROM is divided in two different arrays:
the code array:16/32 Kbytes.
the encryption array:64 bytes.
In addition a third non programmable array is implemented:
the signature array: 4 bytes.
17.2
EPROM Lock System
The program Lock system, when programmed, protects the on-chip program against software
piracy.
17.2.1
Encryption Array
Within the EPROM array are 64 bytes of encryption array that are initially unprogrammed (all
FF’s). Every time a byte is addressed during program verify, 6 address lines are used to select a
byte of the encryption array. This byte is then exclusive-NOR’ed (XNOR) with the code byte, cre-
ating an encrypted verify byte. The algorithm, with the encryption array in the unprogrammed
state, will return the code in its original, unmodified form.
When using the encryption array, one important factor needs to be considered. If a byte has the
value FFh, verifying the byte will produce the encryption byte value. If a large block (>64 bytes)
of code is left unprogrammed, a verification routine will display the content of the encryption
array. For this reason all the unused code bytes should be programmed with random values.
This will ensure program protection.
17.2.2
Program Lock Bits
The three lock bits, when programmed according to Table 17-1., will provide different level of
protection for the on-chip code and data.
U: unprogrammed,
P: programmed
WARNING: Security level 2 and 3 should only be programmed after EPROM and Core
verification.
Table 17-1.
Program Lock bits
Program Lock Bits
Protection Description
Security
level
LB1
LB2
LB3
1U
U
No program lock features enabled. Code verify will still be encrypted by
the encryption array if programmed. MOVC instruction executed from
external program memory returns non encrypted data.
2P
U
MOVC instruction 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 EPROM is
disabled.
3
U
P
U
Same as 2, also verify is disabled.
4
U
P
Same as 3, also external execution is disabled.
相关PDF资料
PDF描述
AT87C54X2-3CSUM IC 8051 MCU 16K EPROM 40DIP
AT87C54X2-3CSUL IC 8051 MCU 16K EPROM 40DIP
AT87C52X2-SLSUM IC 8051 MCU 8K OTP 40MHZ 44PLCC
PIC16LF76-I/SP IC PIC MCU FLASH 8KX14 28DIP
PIC18LF2431-I/SO IC MCU FLASH 8KX16 28SOIC
相关代理商/技术参数
参数描述
AT87C54X2-RLTUM 功能描述:8位微控制器 -MCU OTP C54B/16K 40MHZ 5V COM TEMP 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
AT87C54X2-RLTUV 制造商:ATMEL 制造商全称:ATMEL Corporation 功能描述:8-bit CMOS Microcontroller 16/32 Kbytes ROM/OTP
AT87C54X2-SLRUM 功能描述:8位微控制器 -MCU 16K 40MHz 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
AT87C54X2-SLSUL 功能描述:8位微控制器 -MCU OTP C54/16K 40MHZ 3V COM TEMP 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
AT87C54X2-SLSUM 功能描述:8位微控制器 -MCU OTP C54/16K 40MHZ 5V IND TEMP 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