his is an implementation and simulation of hyperbolic tangent function using Cordic algorithm. The .m files are merely for simulation, verification and test generation but the verilog scripts can be used directly as modules in a project.
There are two main approaches for calculating hyperbolic tangent function using cordic algorithm. The first approach is to directly calculate it using rotaion mode, and the secod approach is to calculate sinh and cosh using vectoring mode and then divide them by another linear cordic algorithm. In this repository the latest is implemented.
All the matlab functions are implemented using fixed point computation
A function that implements cordic tanh algorithm using ROM_lookup.m and cordic_Div.m. This funstion calcuates tanh and output the result. the fixed point attributes are passed to the function using input arguments.
This function returns the tanh inverse number. this part will be a look up table in the HDL implementation.
This function implements cordic division algorithm which is used to divide sinh and cosh in the cordic.m.
This file produces verilog test cases to be fed to the DUT testbench
This files checks the result of the test bench and visualizes all the results to be compared
The verilog code is written in a modular fasion
is the core HDL script which implements the whole process of cordic tanh. note that this module is mainly broken down to two module which are sinh&cosh and division. Each pf these sub modules are pipelined and consist of #Fraction_Length stages so the totall system consists of twice the #Fraction_Length. For example if you choose to work with 8 bits of word length and 6 bits of fraction length, The output should be ready after 12 clock cycles.
This file reads the test.txt files and fed thme to DUT as inputs. Then stores the results to the test_result.txt file.
output of the cordic_test_generator.m and input to the cordic_tb.v
output of the cordic_tb.v and input to the cordic_test_check.m
The final result with 18 bits of word length and 16 bits of fraction length is shown in the figure bellow:
