參數(shù)資料
型號: 9S12D32DGV1
英文描述: 9S12DGDJ64DGV1 Device Guide. also covers 9S12D64. 9S12A64. 9S12D32. and 9S12A32 devices
中文描述: 9S12DGDJ64DGV1設(shè)備指南。也包括9S12D64。 9S12A64。 9S12D32。和9S12A32設(shè)備
文件頁數(shù): 68/126頁
文件大?。?/td> 1809K
代理商: 9S12D32DGV1
MC9S12DJ64 Device User Guide — V01.17
68
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
Thiswillbethemostcommonusageofthesecuredpart.Everythingwillappearthesameasifthepartwas
not secured with the exception of BDM operation. The BDM operation will be blocked.
0
Pierce Oscillator/external clock selected
Table 4-3 Voltage Regulator VREGEN
VREGEN
1
Description
Internal Voltage Regulator enabled
Internal Voltage Regulator disabled, VDD1,2 and
VDDPLL must be supplied externally with 2.5V
0
Table 4-2 Clock Selection Based on PE7
PE7 = XCLKS
Description
相關(guān)PDF資料
PDF描述
9S12DJ64DGV1 9S12DJ64DG Device Guide. also covers 9S12D64. 9S12A64. 9S12D32 and 9S12A32 devices
9S12DJ64-ZIP_PART2 MC9S12DJ64 Users Guides. zip format. part 2
9S12DP256BDGV2 9S12Dx256B Device Guide. also covers C derivatives and 9S12Ax256 devices
9S12DP512DGV1 9S12Dx512 Device Guide
9S12DT128BDGV1 9S12DT128B Device Guide
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
9S12DJ64DGV1 制造商:未知廠家 制造商全稱:未知廠家 功能描述:9S12DJ64DG Device Guide. also covers 9S12D64. 9S12A64. 9S12D32 and 9S12A32 devices
9S12DP256BDGV1 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:Automotive applications
9S12DP256BDGV2 制造商:未知廠家 制造商全稱:未知廠家 功能描述:9S12Dx256B Device Guide. also covers C derivatives and 9S12Ax256 devices
9S12DP512DGV1 制造商:未知廠家 制造商全稱:未知廠家 功能描述:9S12Dx512 Device Guide
9S12DT128BDGV1 制造商:未知廠家 制造商全稱:未知廠家 功能描述:9S12DT128B Device Guide