From 9254063e3ec8067fc5f1098084ea7f435f16da26 Mon Sep 17 00:00:00 2001 From: Arthur Lu Date: Sat, 20 Aug 2022 02:50:14 +0000 Subject: [PATCH] fix program 3 to paritally working, add program3_tb, fix testbench random selection --- RTL/program1_tb.sv | 4 +- RTL/program2_tb.sv | 2 +- RTL/program3_tb.sv | 170 ++++++++++++++++++++++++++++++++++++++++++ firmware/program3.asm | 50 ++++++++----- 4 files changed, 205 insertions(+), 21 deletions(-) create mode 100644 RTL/program3_tb.sv diff --git a/RTL/program1_tb.sv b/RTL/program1_tb.sv index ff877d1..291d9e5 100644 --- a/RTL/program1_tb.sv +++ b/RTL/program1_tb.sv @@ -51,13 +51,13 @@ module program1_tb (); // now select a starting LFSR state -- any nonzero value will do always_comb begin - LFSR_init = $random; + LFSR_init = $urandom; if(!LFSR_init) LFSR_init = 7'b1; // prevents illegal starting state = 7'b0; end // set preamble length for the program run (always > 9 but < 26) always_comb begin - pre_length = $random; + pre_length = $urandom; if(pre_length < 10) pre_length = 10; // prevents pre_length < 10 else if(pre_length > 26) pre_length = 26; // prevets pre_length > 26 end diff --git a/RTL/program2_tb.sv b/RTL/program2_tb.sv index c6224bd..b9ec217 100644 --- a/RTL/program2_tb.sv +++ b/RTL/program2_tb.sv @@ -56,7 +56,7 @@ module program2_tb () ; // set preamble lengths for the four program runs (always > 9 but < 16) always_comb begin - pre_length = 10;//$random>>10 ; // program 1 run + pre_length = $urandom;//$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 diff --git a/RTL/program3_tb.sv b/RTL/program3_tb.sv new file mode 100644 index 0000000..7182cac --- /dev/null +++ b/RTL/program3_tb.sv @@ -0,0 +1,170 @@ +// program3_tb +// testbench for programmable message decryption, space removal (Program #3) +// CSE141L +// runs program 2 (decrypt a message), but with corruption +module program3_tb () ; + logic clk = 1'b0 , // 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 + logic[3:0] pre_length ; // space char. bytes before first char. in message + logic[7:0] message1[49] , // original raw message, in binary + msg_padded1[80], // original message, plus pre- and post-padding w/ ASCII spaces + msg_crypto1[64]; // encrypted message according to the DUT + logic[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 +// 53 characters in length + string str1 = " four score and seven years ago..."; // 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 = " 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 + int space; // counts leading space characters in message + logic[5:0] flipper; // corruptor -- bit flip + logic[79:0] flipped = 80'b0; // tracks which word got a bit flipped +// 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 = $urandom_range(0, 8); + if(pt_no>8) pt_no[3] = 0; // restrict pt_no to 0 through 8 + lfsr_ptrn = LFSR_ptrn[pt_no]; // look up and engage the selected pattern; to data_mem[62] + end + + // now select a starting LFSR state -- any nonzero value will do + always_comb begin + LFSR_init = $urandom; + if(!LFSR_init) LFSR_init = 7'b1; // prevents illegal starting state = 7'b0; + end + + // set preamble length for the program run (always > 9 but < 26) + always_comb begin + pre_length = $urandom; + if(pre_length < 10) pre_length = 10; // prevents pre_length < 10 + else if(pre_length > 26) pre_length = 26; // prevets 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 + file_no = 'b1; // create your output file + #0ns strlen = str1.len; // length of string 1 (# characters between " ") + if(strlen>52) strlen = 52; // clip message at 52 characters + for(space=0;space<24;space++) // count leading spaces in message + if(str1[space]==8'h20) continue; + else break; +// 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, pre_length: %d",lfsr_ptrn,LFSR_init,pre_length); + for(int j=0; j<80; j++) // pre-fill message_padded with ASCII space characters + msg_padded1[j] = 8'h20; // + for(int l=0; l