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???
06/03/05 06:32
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#94284 - [OT] - x86 Segments
Responding to: ???'s previous message
Oleg Sergeev said:
Indeed, on PC there is term "memory segment". Due historical reasons (16-bit addresses) such segments are used for expanding of memory with segment registers CS/DS/SS/ES.

Just for clarification, the 8086 had a 20-bit (1M byte) address space; being a 16-bit processor, it had 16-bit registers. Therefore it used the Segment+Offset scheme to obtain a 20-bit address from two 16-bit registers.

It is not really correct to call this "memory expansion" - it's actually more like PDATA on an 8051 (MOVX @Rn).

for memory expanding, Keil uses term "banking".

8051 Banking is more like the Expanded Memory In old PCs - which was used to expand the x86's addressing beyond 1M byte.

List of 6 messages in thread
TopicAuthorDate
Understanding Code Segments Vs Org            01/01/70 00:00      
   What Assembler?            01/01/70 00:00      
      what assembler            01/01/70 00:00      
   here is not PC            01/01/70 00:00      
      [OT] - x86 Segments            01/01/70 00:00      
      here is not PC            01/01/70 00:00      

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