The aim of this task is to create a self$-$checking testbench for a data transformation program. program. The program assigns different values to the output signal TransformedData depending on the input signals Mode and Data.

The data transformer has three different modes:

$-$ In mode Mode $=0,$ an additional header $00$ is added to Data and the result

TransformedData is assigned.

$-$ In Mode $=1$ mode, the data is encrypted. First, the bitwise XOR of Data and AA$16$ is calculated and the result is then assigned to TransformedData together with a header $01.$

$-$ In Mode $=2,$ the last $4$ bits are extracted. To do this, the bitwise AND

of Data and $0$F$16$ is calculated and the result is then assigned together with a header $10$ to

TransformedData.

$-$ In all other cases, TransformedData is simply set to $0(10$ bits$).$

Headers are always added to the front of the result. For example, for Mode $=1,$ the following applies

TransformedData$=\{2\text{'}$b$01,$ Data $^8$'hAA$\}$;$.$

Note: The "encoding" used here serves as a simple example. In reality, it would only be secure if AA$16$ is replaced by a dynamically and randomly selected key.

The data transformer has the following interface:

module data$\_$transformer

$($ input logic $[7$:$0]$ Data $,$

input logic $[1$:$0]$ Mode $,$

output logic $[9$:$0]$ TransformedData $)$;

$-$ Declare the required inputs and outputs and instantiate the module data$\_$transformer as a unit under test $($UUT$).$ the data$\_$transformer module.

$-$ Test the UUT in Mode $=0$ mode for the inputs Data$=0,$ Data$=255$ and Data$=48.$

$-$ Test the UUT in Mode $=1$ mode for the inputs Data$=15,$ Data$=16$ and Data$=17.$

$-$ Test the UUT in Mode $=2$ for all possible Data inputs.

$-$ Test the UUT in Mode $=3$ for all possible Data inputs.

$-$ Display an appropriate, meaningful error message if the UUT works incorrectly for an input.

works incorrectly for an input.

Notes: Since this is a testbench, you may use constructs such as #$1$;$,$ if$,$ for $($here without generate$)$ etc. in the given initial block. Remember the difference between the operations $==$ and $===.$ Equivalently, there are also operations $!=$ and $!==.$ The code framework issues a warning "SIMULATION TOOK TOO LONG, STOPPING NOW" if your testbench is too slow.

testbench is too slow. In this case, an infinite loop probably exists in your code by mistake.

Note: You can compile and start your testbench with the following command:

Windows: $./$sim$.$bat data$\_$transformer, Otherwise: $./$sim$.$sh data$\_$transformer This tests the transformer in data$\_$transformer.sv$,$ which is correct, so there should be no errors. should be output. Alternatively, you can also use

Windows: $./$sim$.$bat data$\_$transformer custom, Otherwise: $./$sim$.$sh data$\_$transformer custom

execute. This tests the Transformer in data$\_$transformer$\_$error.sv$,$ which should output an error in every mode. an error should be output in every mode.