1 / 6

Memory segmentation and addressing

Memory segmentation and addressing. Von – Newman architecture & Harvard architecture Program Memory & Data Memory Need for Segmentation To implement Harvard architecture Easy to debug Same Interfacing ICs can be used To avoid overlap of stack with normal memory Compatible with 8085.

wentworthj
Télécharger la présentation

Memory segmentation and addressing

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Memory segmentation and addressing • Von – Newman architecture & Harvard architecture • Program Memory & Data Memory • Need for Segmentation • To implement Harvard architecture • Easy to debug • Same Interfacing ICs can be used • To avoid overlap of stack with normal memory • Compatible with 8085

  2. Segmented Memory

  3. Offset Value (16 bits) 0 0 0 0 Segment Register (16 bits) Adder Physical Address (20 Bits) Memory Address Generation • The BIU has a dedicated adder for determining physical memory addresses.

  4. Segment : Offset Address • Logical Address is specified as segment:offset • Physical address is obtained by shifting the segment address 4 bits to the left and adding the offset address. • Thus the physical address of the logical address A4FB:4872 is: A4FB0 + 4872 A9822

  5. Segments, Segment Registers & Offset Registers • Segment Size = 64KB • Maximum number of segments possible = 14 • Logical Address – 16 bits • Physical Address – 20 bits • 2 Logical Addresses for each Segments. • Base Address (16 bits) • Offset Address (16 bits) • Segment registers are used to store the Base address of the segment.

  6. Segments, Segment Registers & Offset Registers • 4 Segments in 8086 • Code Segment (CS) • Data Segment (DS) • Stack Segment (SS) • Extra Segment (ES)

More Related