Electronic Components Datasheet Search |
|
M29DW323DT70ZE6E Datasheet(PDF) 43 Page - Numonyx B.V |
|
M29DW323DT70ZE6E Datasheet(HTML) 43 Page - Numonyx B.V |
43 / 51 page 43/51 M29DW323DT, M29DW323DB APPENDIX C. EXTENDED MEMORY BLOCK The M29DW323D has an extra block, the Extend- ed Block, that can be accessed using a dedicated command. This Extended Block is 32 KWords in x16 mode and 64 KBytes in x8 mode. It is used as a security block (to provide a permanent security identifica- tion number) or to store additional information. The Extended Block is either Factory Locked or Customer Lockable, its status is indicated by bit DQ7. This bit is permanently set to either ‘1’ or ‘0’ at the factory and cannot be changed. When set to ‘1’, it indicates that the device is factory locked and the Extended Block is protected. When set to ‘0’, it indicates that the device is customer lockable and the Extended Block is unprotected. Bit DQ7 being permanently locked to either ‘1’ or ‘0’ is another security feature which ensures that a customer lockable device cannot be used instead of a facto- ry locked one. Bit DQ7 is the most significant bit in the Extended Block Verify Code and a specific procedure must be followed to read it. See “Extended Memory Block Verify Code” in Tables 3 and 4, Bus Opera- tions, BYTE = VIL and Bus Operations, BYTE = VIH, respectively, for details of how to read bit DQ7. The Extended Block can only be accessed when the device is in Extended Block mode. For details of how the Extended Block mode is entered and exited, refer to the Enter Extended Block Com- mand and Exit Extended Block Command para- graphs, and to Tables 5 and 6, “Commands, 16-bit mode, BYTE = VIH” and “Commands, 8-bit mode, BYTE = VIL”, respectively. Factory Locked Extended Block In devices where the Extended Block is factory locked, the Security Identification Number is writ- ten to the Extended Block address space (see Ta- ble 31., Extended Block Address and Data) in the factory. The DQ7 bit is set to ‘1’ and the Extended Block cannot be unprotected. Customer Lockable Extended Block A device where the Extended Block is customer lockable is delivered with the DQ7 bit set to ‘0’ and the Extended Block unprotected. It is up to the customer to program and protect the Extended Block but care must be taken because the protec- tion of the Extended Block is not reversible. There are two ways of protecting the Extended Block: ■ Issue the Enter Extended Block command to place the device in Extended Block mode, then use the In-System Technique with RP either at VIH or at VID (refer to APPENDIX D., In-System Technique and to the corresponding flowcharts, Figures 22 and 23, for a detailed explanation of the technique). ■ Issue the Enter Extended Block command to place the device in Extended Block mode, then use the Programmer Technique (refer to APPENDIX D., Programmer Technique and to the corresponding flowcharts, Figures 20 and 21, for a detailed explanation of the technique). Once the Extended Block is programmed and pro- tected, the Exit Extended Block command must be issued to exit the Extended Block mode and return the device to Read mode. Table 31. Extended Block Address and Data Note: 1. See Tables 23 and 24, Top and Bottom Boot Block Addresses. Device Address(1) Data x8 x16 Factory Locked Customer Lockable M29DW323DT 3F0000h-3F000Fh 1F8000h-1F8007h Security Identification Number Determined by Customer 3F0010h-3FFFFFh 1F8008h-1FFFFFh Unavailable M29DW323DB 000000h-00000Fh 000000h-000007h Security Identification Number Determined by Customer 000010h-00FFFFh 000008h-007FFFh Unavailable |
Similar Part No. - M29DW323DT70ZE6E |
|
Similar Description - M29DW323DT70ZE6E |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.COM |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Datasheet Upload | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |