Registers and flipflops

Try to implement both of the following circuits. If you can't do both, do at least one.

Using a shift register

Using a 4-bit shift register and a 4-bit comparator (7485), implement in diglog a clocked circuit that receives a serial input stream and produces a serial output stream. Your circuit should output a 1 if and only if the last four input bits are 1011. For example, if the input stream is 001101100010101100 the output stream should be 000000100000000100. FTP your completed circuit to ~/csci/255/home9a.lgf.

Using a flip-flop

Using a single JK flip-flop and a few other miscellaneous gates, construct a clocked circuit that receives a input stream and produces an output stream. The output stream should contain a 1 only when the input stream makes a transition from 0 to 1. For example, if the input stream is 001101100010101100 the output stream should be 001001000010101000.

FTP your completed circuit to ~/csci/255/home9b.lgf.


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