From 9a8c9a3771fc3f09db1b2389be65abbd541407d0 Mon Sep 17 00:00:00 2001 From: Arthur Lu Date: Wed, 17 Aug 2022 18:01:09 -0700 Subject: [PATCH] add program2 testbench --- RTL/program2_tb.sv | 156 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 156 insertions(+) create mode 100644 RTL/program2_tb.sv diff --git a/RTL/program2_tb.sv b/RTL/program2_tb.sv new file mode 100644 index 0000000..5a4d6a9 --- /dev/null +++ b/RTL/program2_tb.sv @@ -0,0 +1,156 @@ +// program2_tb +// testbench for programmable message decryption (Program #2) +// CSE141L +// runs program 2 (decrypt a message) +module program2_tb () ; +// DUT interface -- four one-bit wires, three to DUT, one from + bit clk , // advances simulation step-by-step + init = 1'b1 , // init (reset) command to DUT + start = 1'b1 ; // req (start program) command to DUT + wire done ; // done flag returned by DUT +// test bench parameters + bit [3:0] pre_length ; // space char. bytes before first char. in message + bit [7:0] message1[54] , // original raw message, in binary + msg_padded1[64], // original message, plus pre- and post-padding w/ ASCII spaces + msg_crypto1[64]; // encrypted message according to the DUT + bit [6:0] lfsr_ptrn , // chosen one of 9 maximal length 7-tap shift reg. ptrns + LFSR_ptrn[9] , // the 9 candidate maximal-length 7-bit LFSR tap ptrns + lfsr1[64] , // states of program 1 encrypting LFSR + LFSR_init ; // one of 127 possible NONZERO starting states + int score ; // count of correct encyrpted characters +// our original American Standard Code for Information Interchange message follows +// note in practice your design should be able to handle ANY ASCII string that is +// restricted to characters between space (0x20) and script f (0x9f) and shorter than +// 55 characters in length + string str1 = "Mr. Watson, come here. I want to see you."; // sample program 1 input +// string str1 = " Knowledge comes, but wisdom lingers. "; // alternative inputs +// string str1 = " 01234546789abcdefghijklmnopqrstuvwxyz. "; // (make up your own, +// string str1 = " f A joke is a very serious thing."; // as well) +// string str1 = " Ajok "; // +// string str1 = "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"; +// string str1 = " Knowledge comes, but wisdom lingers. "; // + +// displayed encrypted string will go here: + string str_enc1[64]; // program 1 desired output will go here + int strlen; // incoming string length + int pt_no; // select LFSR pattern, value 0 through 8 + int file_no; // write to file +// the 8 possible maximal-length feedback tap patterns from which to choose + assign LFSR_ptrn[0] = 7'h60; // 110_0000 + assign LFSR_ptrn[1] = 7'h48; + assign LFSR_ptrn[2] = 7'h78; + assign LFSR_ptrn[3] = 7'h72; + assign LFSR_ptrn[4] = 7'h6A; + assign LFSR_ptrn[5] = 7'h69; + assign LFSR_ptrn[6] = 7'h5C; + assign LFSR_ptrn[7] = 7'h7E; + assign LFSR_ptrn[8] = 7'h7B; + always_comb begin + pt_no = 0; //$random>>22; // or pick a specific one + if(pt_no>8) pt_no[3] = 0; // restrict to 0 through 8 (our legal patterns) + lfsr_ptrn = LFSR_ptrn[pt_no]; // engage the selected pattern + end +// now select a starting LFSR state -- any nonzero value will do + always_comb begin + LFSR_init = 'b1;//$random>>2; // or set a value, such as 7'b1, for debug + if(!LFSR_init) LFSR_init = 7'b1; // prevents illegal starting state = 7'b0; + end + +// set preamble lengths for the four program runs (always > 9 but < 16) + always_comb begin + pre_length = 10;//$random>>10 ; // program 1 run + if(pre_length < 10) pre_length = 10; // prevents pre_length < 10 + else if(pre_length > 26) pre_length = 26; + end + +// ***** instantiate your own top level design here ***** + top_level dut( + .clk (clk ), // input: use your own port names, if different + .init (init ), // input: some prefer to call this ".reset" + .req (start), // input: launch program + .ack (done ) // output: "program run complete" + ); + + initial begin +//***** pre-load your instruction ROM here or inside itself ***** +// $readmemb("encoder.bin", dut.instr_rom.rom); +// you may also pre-load desired constants, etc. into +// your data_mem here -- the upper addresses are reserved for your use +// dut.data_mem.DM[128]=8'hfe; //whatever constants you want +// to display to console, change this line to file_no = 'b1; + file_no = 'b1; +// file_no = $fopen("msg_decoder_out.txt"); // create your output file + #0ns strlen = str1.len; // length of string 1 (# characters between " ") + if(strlen>52) strlen = 52; // clip message at 52 characters +// program 1 -- precompute encrypted message + lfsr1[0] = LFSR_init; // any nonzero value (zero may be helpful for debug) + $fdisplay(file_no,"run encryption program; original message = "); + $fdisplay(file_no,"%s",str1); // print original message in transcript window + $fdisplay(file_no,"LFSR_ptrn = 0x%h, LFSR_init = 0x%h",lfsr_ptrn,LFSR_init); + $fdisplay(file_no,"pt_no = %d",pt_no); + +// will subtract 0x20 from each preamble and message character + for(int j=0; j<64; j++) // pre-fill message_padded with ASCII space characters + msg_padded1[j] = 8'h20; // + for(int l=0; l