| 数据搜索系统,热门电子元器件搜索 |
|
PSD913F2 数据表(PDF) 32 Page - STMicroelectronics |
|
|
|||||||||||||||||||||||||||||
PSD913F2 数据表(HTML) 32 Page - STMicroelectronics |
|
32 / 94 page ![]() The PSD9XX Functional Blocks (cont.) Level 1 SRAM, I /O Level 2 Secondary Flash Memory Highest Priority Lowest Priority Level 3 Main Flash Memory Figure 5. Priority Level of Memory and I/O Components 9.1.3.1. Memory Select Configuration for MCUs with Separate Program and Data Spaces The 8031 and compatible family of microcontrollers, which includes the 80C51, 80C151, 80C251, 80C51XA, and the C500 family have separate address spaces for code memory (selected using PSEN) and data memory (selected using RD). Any of the memories within the PSD9XX can reside in either space or both spaces. This is controlled through manipulation of the VM register that resides in the PSD’s CSIOP space. The VM register is set using PSDsoft to have an initial value. It can subsequently be changed by the microcontroller so that memory mapping can be changed on-the-fly. For example, you may wish to have SRAM and Flash in Data Space at boot, and Boot Block in Program Space at boot, and later swap Boot Block and Flash. This is easily done with the VM register by using PSDsoft to configure it for boot up and having the microcon- troller change it when desired. Table 13 describes the VM Register. Bit 7* Bit 6* Bit 5* Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 FL_Data Boot_Data FL_Code Boot_Code SRAM_Code ** * 0 = RD 0 = RD 0 = PSEN 0 = PSEN 0 = PSEN can’t can’t can’t can’t can’t access access access access access Flash Secondary Flash Secondary SRAM Flash Flash ** * 1 = RD 1 = RD 1 = PSEN 1 = PSEN 1 = PSEN access access access access access Flash Secondary Flash Secondary SRAM Flash Flash Table 13. VM Register NOTE: Bits 5-7 are not used, should set to “0”. PSD9XX Family Preliminary Information 28 |
|
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 |