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Design
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WATCHVHD is a top level VHDL type project of a Stop Watch. 

DESIGN TYPE:
        Foundation ISE (chip 3S100E VQ100 -4)

CONTROLS 
Inputs:
* CLK -System clock for the Watch design.
* STRTSTOP -Starts and stops the stoopwatch. This is an active-low signal 
            which acts like the start/stop button on a runner's stop-watch.
* RESET -Resets the stopwatch to 00.0 after it has been stopped.

Outputs:
* TENSOUT[6:0] -7-bit bus which represents the Tens digit of the stopwatch 
                value. This bus is in 7-segment display format to be viewable 
                on the 7-segment LED display. 
* ONESOUT[6:0] -similar to TENSOUT bus above, but represents the Ones digit 
                of the stopwatch value.
* TENTHSOUT[9:0] -10-bit bus which represents the Tenths digit of the stopwatch 
                  value. This bus is one-hot encoded.

DESCRIPTION:
* STOPWATCH -Top level HDL file.
* STMACH_V -State Machine macro. 
* CNT60 -VHDL module which counts from 0 to 59, decimal. This macro 
		has two 4-bit outputs, which represent the 'ones' and 'tens' digits of 
		the decimal values, respectively.
* DCM1 -A single DCM clocking module created with Xilinx Architecture Wizard.
* DECODE -HDL-based macro.  This macro converts a binary input to a one-hot output.
* TENTHS -A Coregen 10-bit, one-hot encoded counter. This macro outputs the 
          'tenths' digit of the watch value as a 10-bit one-hot encoded value.
* HEX2LED -HDL-based macro. This macro decodes the ones and tens digit values 
		from hexadecimal to 7-segment display format.

SIMULATION:
Behavioural and RTL Simulation done using Test bench file (stopwatch_tb.vhd). 


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