Please answer the following questions to signify your successful completion of U
ID: 645293 • Letter: P
Question
Please answer the following questions to signify your successful completion of Unit 5. Save your work into a Word or Notepad document. Upload your file into this submission area to be score.
In total, how many 8-bit registers are there in the Intel 80x86 CPU design presented in class? Name one of these 8-bit registers.
In total, how many 16-bit registers are there in the Intel 80x86 CPU design presented in class? Name one of these 16-bit registers.
In total, how many 32-bit registers are there in the Intel 80x86 CPU design presented in class? Name one of these 32-bit registers.
Name an important difference between the registers that have three-letter names and the ones that have two-letter names.
Way back in 1981, IBM released the first generation of its Personal Computers with an Intel 8088 CPU chip inside. From that time forward to today, one of Intel's most important design goals has been to provide backward compatibility in the interest of preserving the investment of its existing customer base. Intel hardware designers have continually ensured that programs written for its older chips continue to run, unmodified, on its newer chips. This original 8088 CPU has only 16-bit registers. Even today, on the Pentium 80x86 CPUs, these same registers still exist. Name them.
In addition to having so few registers, Intel's CPU registers overlap on top of one another. If your code sets bit 8 in ECX, there are two other registers whose bits get altered. Name these registers and which bits of these registers that will get altered.
In addition to have so few registers, Intel's CPU registers overlap on top of one another. If your code sets bit 3 in BX, there will be two other register whose bits get altered. Name these registers and which bits of these registers that will get altered.
Explanation / Answer
1. There are four 8-Bit registers named AX,BX,CX,DX.
2. There are Eight 16-Bit Registers. For example: BP,SI,DI,SP
3. Far pointers are 32 bit registers.
4. In 8086, earlier basic general registers are 2 letters long in name but when 16 bit indexing came, the registers were extended and then they got 3 or more letters names.
5. The 16 bit registers and one MB address space is same. Both 8088 and 8086 have same EU i.e. execution unit.
6. registers eax and edx will change.
7.bx is base pointer for memory address. It is ued in indexed adressing.