In this chapter, we will reimplement the some of the designs of previous chapters using SystemVerilog to learn and compare the SystemVerilog with Verilog. Also, the compiler can catch the error if these new always-blocks are not implemented according to predefined rules. When input PL is HIGH, data enters the register seria lly at the input DS. When the parallel-load input (PL) is LOW, parallel data from the inputs D0 to D7 are loaded into the register asynchronously. ‘always_ff’, ‘always_comb’ and ‘always_latch’, which remove the Verilog’s ambiguity between simulation and synthesis results. The 74LV165A is an 8-bit parallel-load or serial-in shift register with complementary serial outputs (Q7 and Q7) available from the last stage. Most importantly, it replaces the general purpose ‘always’ block with three different blocks i.e. C (structure, and typedef), C++ (class and object) and VHDL (enumerated data type, continue and break statements).
The SystemVerilog language is the superset of Verilog and contains various features of other programming language i.e. Solution Manual (Complete Download) For Digital Design: With an Introduction to the Verilog HDL, VHDL, and SystemVerilog, 6th Edition By M. The user-defined type (enumerated type) can not be defined in Verilog, which is a very handy tool in VHDL for designing the FSM.there is no ambiguity between the simulation and synthesize results. Whereas the behavior of VHDL is accurate, i.e. Any misuse of ‘always’ block will result in different ‘simulation’ and ‘synthesis’ results, which is very hard to debug. Verilog - Modules (cont.) System Verilog instantiation short cuts These are useful when most all pins/wires have the same name shiftreg shiftreg1(.clk (clk ).resetn (resetn ).dataena (dataena ).serialdata (serialdata ). It is the designer’s responsibility to use it correctly, as Verilog does not provide any option to check the rules. The general purpose ‘always’ block’ of Verilog needs to be used very carefully.Also due to this reason, it may take more time to write the VHDL codes than the Verilog codes. VHDL is strongly typed language, therefore lots of conversions may require in it, which make the codes more complex than the Verilog codes.For example 1st i got the data of 6 bit length at that time that data should be latched then it should get serialized. Verilog codes are smaller as compare to VHDL codes. ya input is fixed length of 16 bit but this parallel to serial converter logic should be programmable when ever the data will arrive then dat should get serialized.