Electronic Components Datasheet Search |
|
X68C64P Datasheet(PDF) 6 Page - Xicor Inc. |
|
X68C64P Datasheet(HTML) 6 Page - Xicor Inc. |
6 / 12 page X68C64 6 WRITE AA TO X555 WRITE 55 TO XAAA WRITE A0 TO X555 PERFORM BYTE OR PAGE WRITE OPERATIONS WAIT tWC EXIT ROUTINE X = A 12: A 12 = 1 IF DATA TO BE WRITTEN IS WITHIN ADDRESS 1000 TO 1FFF. A 12 = 0 IF DATA TO BE WRITTEN IS WITHIN ADDRESS 0000 TO 0FFF. DATA PROTECTION The X68C64 provides two levels of data protection through software control. There is a global software data protection feature similar to the industry standard for E2PROMs and a new Block Protect write lockout protec- tion providing a secondary level of data security. Writing with SDP Setting write lockout is accomplished by writing a five- byte command sequence, opening access to the Block Protect Register (BPR). After the fifth byte is written, the user writes to the BPR, selecting which blocks to protect or unprotect. All write operations, both the command sequence and writing the data to the BPR, must conform to the page write timing requirements. 3868 FHD F09 Software Data Protection Software Data Protection (SDP) is employed to protect the entire array against inadvertent writes. To write to the X68C64, a three-byte command sequence must precede the byte(s) being written. All write operations, both the command sequence and any data write operations, must conform to the page write timing requirements. Block Protect Write Lockout The X68C64 provides a secondary level of data security referred to as Block Protect write lockout. This is ac- cessed through an extension of the SDP command sequence. Block Protect allows the user to lockout writes to any 1K x 8 blocks of memory. Unlike SDP which prevents inadvertent writes, but still allows easy system access to writing the memory, Block Protect will lockout all attempts unless it is specifically disabled by the host. This could be used to set a higher level of protection in a system where a portion of the memory is used for Program Storage and another portion is used as Data Storage. Block Protect Register Format 3868 FHD F11 6 5 43 2 1 0 7 0000–03FF 0400–07FF 0800–0BFF 0C00–0FFF 1000–13FF 1400–17FF 1800–1BFF 1C00–1FFF BLOCK ADDRESS 1 = Protect, 0 = Unprotect Block Specified MSB LSB Setting BPR Command Sequence 3868 FHD F12 WRITE AA TO X555 WRITE BPR MASK VALUE TO ANY ADDRESS WAIT tWC EXIT ROUTINE WRITE 55 TO XAAA WRITE C0 TO XAAA WRITE AA TO X555 WRITE A0 TO X555 X = A 12: A 12 = 1 IF PROGRAM BEING EXECUTED IS WITHIN 0000 TO 0FFF. A 12 = 0 IF PROGRAM BEING EXECUTED RESIDES WITHIN 1000 TO 1FFF. |
Similar Part No. - X68C64P |
|
Similar Description - X68C64P |
|
|
Link URL |
Privacy Policy |
ALLDATASHEET.NET |
Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | 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 |