参数资料
型号: MC9S12DG256CVFU
厂商: MOTOROLA INC
元件分类: 微控制器/微处理器
英文描述: 16-BIT, FLASH, 25 MHz, MICROCONTROLLER, PQFP80
封装: QFP-80
文件页数: 101/128页
文件大小: 2174K
代理商: MC9S12DG256CVFU
MC9S12DP256B Device User Guide — V02.13
74
4.3 Security
The device will make available a security feature preventing the unauthorized read and write of the
memory contents. This feature allows:
Protection of the contents of FLASH,
Protection of the contents of EEPROM,
Operation in single-chip mode,
Operation from external memory with internal FLASH and EEPROM disabled.
The user must be reminded that part of the security must lie with the user’s code. An extreme example
would be user’s code that dumps the contents of the internal program. This code would defeat the purpose
of security. At the same time the user may also wish to put a back door in the user’s program. An example
of this is the user downloads a key through the SCI which allows access to a programming routine that
updates parameters stored in EEPROM.
4.3.1 Securing the Microcontroller
Once the user has programmed the FLASH and EEPROM (if desired), the part can be secured by
programming the security bits located in the FLASH module. These non-volatile bits will keep the part
secured through resetting the part and through powering down the part.
The security byte resides in a portion of the Flash array.
Check the Flash Block User Guide for more details on the security configuration.
4.3.2 Operation of the Secured Microcontroller
4.3.2.1 Normal Single Chip Mode
This will be the most common usage of the secured part. Everything will appear the same as if the part was
not secured with the exception of BDM operation. The BDM operation will be blocked.
4.3.2.2 Executing from External Memory
The user may wish to execute from external space with a secured microcontroller. This is accomplished
by resetting directly into expanded mode. The internal FLASH and EEPROM will be disabled. BDM
operations will be blocked.
Table 4-3 Voltage Regulator VREGEN
VREGEN
Description
1
Internal Voltage Regulator enabled
0
Internal Voltage Regulator disabled, VDD1,2 and
VDDPLL must be supplied externally with 2.5V
相关PDF资料
PDF描述
MC9S12DT256BMPV 16-BIT, FLASH, 25 MHz, MICROCONTROLLER, PQFP112
MC9S12DJ256CMFU 16-BIT, FLASH, 25 MHz, MICROCONTROLLER, PQFP80
MC9S12DG256CCFU 16-BIT, FLASH, 25 MHz, MICROCONTROLLER, PQFP80
MC9S12DT256CMPV 16-BIT, FLASH, 25 MHz, MICROCONTROLLER, PQFP112
MC9S12DG256BMFU 16-BIT, FLASH, 25 MHz, MICROCONTROLLER, PQFP80
相关代理商/技术参数
参数描述
MC9S12DG256CVPV 制造商:Rochester Electronics LLC 功能描述: 制造商:Freescale Semiconductor 功能描述:
MC9S12DG256MFUE 功能描述:16位微控制器 - MCU BARRACUDA4 MOS13 L01Y RoHS:否 制造商:Texas Instruments 核心:RISC 处理器系列:MSP430FR572x 数据总线宽度:16 bit 最大时钟频率:24 MHz 程序存储器大小:8 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:2 V to 3.6 V 工作温度范围:- 40 C to + 85 C 封装 / 箱体:VQFN-40 安装风格:SMD/SMT
MC9S12DG256MPV 制造商:Freescale Semiconductor 功能描述: 制造商:FREESCALE-SEMI 功能描述:
MC9S12DG256MPVE 功能描述:16位微控制器 - MCU 256K FLASH HCS12 MCU EPP RoHS:否 制造商:Texas Instruments 核心:RISC 处理器系列:MSP430FR572x 数据总线宽度:16 bit 最大时钟频率:24 MHz 程序存储器大小:8 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:2 V to 3.6 V 工作温度范围:- 40 C to + 85 C 封装 / 箱体:VQFN-40 安装风格:SMD/SMT
MC9S12DG256VFUE 功能描述:16位微控制器 - MCU BARRACUDA4 MOS13 L01Y RoHS:否 制造商:Texas Instruments 核心:RISC 处理器系列:MSP430FR572x 数据总线宽度:16 bit 最大时钟频率:24 MHz 程序存储器大小:8 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:2 V to 3.6 V 工作温度范围:- 40 C to + 85 C 封装 / 箱体:VQFN-40 安装风格:SMD/SMT