| 数据搜索系统,热门电子元器件搜索 |
|
AT89C5131A-RDTIM 数据表(PDF) 41 Page - ATMEL Corporation |
|
|
|||||||||||||||||||||||||||||
AT89C5131A-RDTIM 数据表(HTML) 41 Page - ATMEL Corporation |
|
41 / 184 page ![]() 41 AT89C5130A/31A-M 4337C–USB–02/05 Table 43. Program Lock Bits of the SSB Notes: 1. U: unprogrammed or "one" level. 2. P: programmed or “zero” level. 3. X: don’t care 4. WARNING: Security level 2 and 3 should only be programmed after Flash and code verification. Flash Memory Status AT89C5130A/31A-M parts are delivered with the ISP boot in the Flash memory. After ISP or parallel programming, the possible contents of the Flash memory are summa- rized in Figure 19: Figure 19. Flash Memory Possible Contents Memory Organization In the AT89C5130A/31A-M, the lowest 16/32K of the 64 Kbyte program memory address space is filled by internal Flash. When the EA is pin high, the processor fetches instructions from internal program Flash. Bus expansion for accessing program memory from 16/32K upward is automatic since external instruction fetches occur automatically when the program counter exceeds 3FFFh (16K) or 7FFFh (32K). If the EA pin is tied low, all program memory fetches are from external memory. If all storage is on chip, then byte location 3FFFh (16K) or 7FFFh (32K) should be left vacant to prevent and undesired pre-fetch from external program memory address 4000h (16K) or 8000h (32K). Program Lock Bits Protection Description Security Level LB0 LB1 1 U U No program lock features enabled. 2 P U ISP programming of the Flash is disabled. 3 X P Same as 2, also verify through ISP programming interface is disabled. 0000h Virgin Default Virgin After ISP After parallel programming After parallel programming After parallel programming Application Application After ISP or Dedicated ISP Dedicated ISP 7FFFh AT89C5131A-M Application Virgin or Application Virgin or Application 3FFFh AT89C5130A-M |
|
链接网址 |
| ALLDATASHEET是否为您带来帮助? [ DONATE ] |
关于 Alldatasheet | 广告服务 | 联系我们 | 隐私政策 | 数据表链接 | 链接交换 | 制造商名单 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 |