 |
数据搜索系统，热门电子元器件搜索 |
|
|
数据搜索系统，热门电子元器件搜索 |
|
DVR 数据表(PDF) 54 Page - Microchip Technology |
|
|
|||||||||||||||||||||||||||||
DVR 数据表(HTML) 54 Page - Microchip Technology |
|
|
54 / 416 page  PIC24FJ256GA705 FAMILY DS30010118D-page 54 2016-2018 Microchip Technology Inc. 4.2.5 EXTENDED DATA SPACE (EDS) The Extended Data Space (EDS) allows PIC24F devices to address a much larger range of data than would otherwise be possible with a 16-bit address range. EDS includes any additional internal data memory not directly accessible by the lower 32-Kbyte data address space and any external memory through EPMP. In addition, EDS also allows read access to the program memory space. This feature is called Program Space Visibility (PSV) and is discussed in detail in Section 4.3.3 “Reading Data from Program Memory Using EDS”. Figure 4-3 displays the entire EDS space. The EDS is organized as pages, called EDS pages, with one page equal to the size of the EDS window (32 Kbytes). A par- ticular EDS page is selected through the Data Space Read Page register (DSRPAG) or the Data Space Write Page register (DSWPAG). For PSV, only the DSRPAG register is used. The combination of the DSRPAG register value and the 16-bit wide data address forms a 24-bit Effective Address (EA). The data addressing range of the PIC24FJ256GA705 family devices depends on the version of the Enhanced Parallel Master Port implemented on a particular device; this is, in turn, a function of device pin count. Table 4-12 lists the total memory accessible by each of the devices in this family. For more details on accessing external memory using EPMP, refer to the “dsPIC33/PIC24 Fam- ily Reference Manual”, “Enhanced Parallel Master Port (EPMP)” (DS39730). . FIGURE 4-3: EXTENDED DATA SPACE TABLE 4-12: TOTAL ACCESSIBLE DATA MEMORY Family Internal RAM External RAM Access Using EPMP PIC24FJXXXGA70X 16K 1K Note: Accessing Page 0 in the EDS window will generate an address error trap as Page 0 is the base data memory (data locations, 0800h to 7FFFh, in the lower Data Space). 0000h Special Registers 32-Kbyte EDS 8000h Program Memory DSxPAG = 002h DSxPAG = 1FFh DSRPAG = 200h DSRPAG = 3FFh Function 018000h 01FFFEh 000000h 7F8001h FFFFFEh 007FFEh 7FFFFFh Program Space 0800h FFFEh EDS Pages EPMP Memory Space(1) External Memory Access Using EPMP(1) FF8000h DSRPAG = 2FFh 7F8000h 7FFFFEh Access Program Space Access Program Space Access DSRPAG = 300h 000001h 007FFFh Program Space Access Note 1: The range of addressable memory available is dependent on the device pin count and EPMP implementation. External Memory Access Using EPMP(1) Internal Data Memory Space (Lower Word) (Lower Word) (Upper Word) (Upper Word) Window DSxPAG = 001h 008000h 008800h External Memory Access Using EPMP(1) 047FEh 04800h Unimplemented |
|
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 |
Chinese ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
