EECE $3435$ Lab $07$: Data Transfer and Arithmetic Instructions

A$.$ Objectives: to understand and experiment on data transfer and arithmetic instructions

B$.$ Resources

$1.$ Online resources

$2.$ Textbook

C$.$ Lab Preparation

$1.$ Use online resources or the textbook to understand the debug commands and assembly instructions used in the assignment.

$2.$ Start the Debug Application.

First fill the memory with some data by executing the following command:

$-$f $0$ ffff AA $3$A $59281$B A$6$ C$1$ B$2$ CC

Note that in the lab report, you will be required to show the results you obtained in your experiments. You thus need to take screenshots of your work.

D$.$ The Lab

Part $1-$ Data Transfer Instructions

$1.$ The following XCHG instruction tries to swap the the word contents at $200$ and $400$ in the data segment. Try to assemble and execute it$.$ What do you find?

XCHG $[200],[400]$

$2.$ If the above instruction cannot swap the two words at $200$ and $400$ in the data segment, explain why?

$3.$ Design your own instruction sequence to swap the two words at $200$ and $400,$ using XCHG only.

$4.$ Assemble and execute your sequence of instructions, and verify the sequence works as designed.

$5.$ Explain what XLAT does.

$6.$ Design a sequence of instructions using XLAT to translate the index of $5$ in AL to the byte content at the physical address $2$B$605$H; at the end of the execution of the sequence of instructions, the $5$ in AL becomes the byte content at the physical address $2$B$605$H$.$