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ericw |
/*
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--------------------------------------------------------------------------------
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Module : boot_code.h
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--------------------------------------------------------------------------------
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Function:
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- Boot code for a processor core.
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Instantiates:
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- Nothing.
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Notes:
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- For testing (@ core.v):
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CLR_BASE = 'h0;
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CLR_SPAN = 2; // gives 4 instructions
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INTR_BASE = 'h20; // 'd32
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INTR_SPAN = 2; // gives 4 instructions
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--------------------------------------------------------------------------------
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*/
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/*
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-------------------------
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-- external parameters --
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-------------------------
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*/
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`include "op_encode.h"
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`include "reg_set_addr.h"
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/*
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------------------------------------------------------------
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-- defines that make programming code more human readable --
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------------------------------------------------------------
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*/
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`define s0 2'd0
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`define s1 2'd1
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`define s2 2'd2
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`define s3 2'd3
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`define _ 1'b0
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`define P 1'b1
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//
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`define op_rd_i op_rd_i[9:4]
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`define op_rd_ix op_rd_ix[9:4]
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//
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`define op_jmp_iez op_jmp_iez[9:5]
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`define op_jmp_ilz op_jmp_ilz[9:5]
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`define op_jmp_ilez op_jmp_ilez[9:5]
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`define op_jmp_igz op_jmp_igz[9:5]
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`define op_jmp_igez op_jmp_igez[9:5]
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`define op_jmp_iglz op_jmp_iglz[9:5]
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`define op_jmp_i op_jmp_i[9:5]
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//
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`define op_wr_i op_wr_i[9:4]
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`define op_wr_ix op_wr_ix[9:4]
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//
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`define op_jmp_ie op_jmp_ie[9:5]
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`define op_jmp_il op_jmp_il[9:5]
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`define op_jmp_ile op_jmp_ile[9:5]
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`define op_jmp_iug op_jmp_iug[9:5]
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`define op_jmp_iuge op_jmp_iuge[9:5]
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`define op_jmp_igl op_jmp_igl[9:5]
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//
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`define op_byt_i op_byt_i[9:8]
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//
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`define op_shl_i op_shl_i[9:6]
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`define op_shl_iu op_shl_iu[9:6]
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`define op_add_i op_add_i[9:6]
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/*
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----------------------------------------
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-- initialize: fill with default data --
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----------------------------------------
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*/
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integer i;
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initial begin
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/* // fill with nop (some compilers need this)
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for ( i = 0; i < CAPACITY; i = i+1 ) begin
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ram[i] = { op_nop, `_, `_, `s0, `s0 };
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end
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*/
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/*
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---------------
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-- boot code --
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---------------
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*/
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// Thread 0 : test stack 1 for depth and error reporting
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// Thread 1 : test stack 1 clear instruction
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// All other threads : loop forever
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///////////////
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// clr space //
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///////////////
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// thread 0
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i='h0; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h100 ; // addr
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i=i+1; ram[i] = { op_gto, `P, `_, `s2, `s0 }; // goto, pop s2 (addr)
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//
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// thread 1
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i='h4; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h200 ; // addr
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i=i+1; ram[i] = { op_gto, `P, `_, `s2, `s0 }; // goto, pop s2 (addr)
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// and the rest (are here on Gilligan's Isle)
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i='h8; ram[i] = { `op_jmp_i, -5'h1, `_, `_, `s0, `s0 }; // loop forever
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i=i+4; ram[i] = { `op_jmp_i, -5'h1, `_, `_, `s0, `s0 }; // loop forever
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i=i+4; ram[i] = { `op_jmp_i, -5'h1, `_, `_, `s0, `s0 }; // loop forever
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i=i+4; ram[i] = { `op_jmp_i, -5'h1, `_, `_, `s0, `s0 }; // loop forever
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i=i+4; ram[i] = { `op_jmp_i, -5'h1, `_, `_, `s0, `s0 }; // loop forever
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i=i+4; ram[i] = { `op_jmp_i, -5'h1, `_, `_, `s0, `s0 }; // loop forever
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////////////////
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// intr space //
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////////////////
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///////////////////////
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// code & data space //
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///////////////////////
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// test correct stack depth and error reporting, result in s0
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// Correct functioning is s0 = 'd6 ('h6).
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//
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// s0 : final test result
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// s1 : test stack
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// s2 : sub addr
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// s3 : running test result, subroutine return address
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//
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// setup running test result:
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i='h100; ram[i] = { `op_byt_i, 8'd0, `_, `_, `s0, `s3 }; // 0=>s3
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// check for no stack errors
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h910 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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i=i+1; ram[i] = { `op_jmp_iez, 5'd1, `_, `_, `s0, `s0 }; // (s0==0) ? skip
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i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s3 }; // s3-1=>s3, pop s3 (Y)
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i=i+1; ram[i] = { `op_add_i, 6'd1, `P, `P, `s0, `s3 }; // s3+1=>s3, pop both
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// fill s1
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h940 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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// check for push error
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h910 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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i=i+1; ram[i] = { `op_shl_iu, -6'd8, `_, `P, `s0, `s0 }; // s0>>8=>s0, pop s0
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i=i+1; ram[i] = { `op_jmp_iez, 5'd1, `_, `_, `s0, `s0 }; // (s0==0) ? skip
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i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s3 }; // s3-1=>s3, pop s3
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i=i+1; ram[i] = { `op_add_i, 6'd1, `P, `P, `s0, `s3 }; // s3+1=>s3, pop both
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// pop&push s/b OK
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i=i+1; ram[i] = { op_cpy, `_, `P, `s2, `s1 }; // s2=>s1
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// check for no stack errors
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h910 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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i=i+1; ram[i] = { `op_jmp_iez, 5'd1, `_, `_, `s0, `s0 }; // (s0==0) ? skip
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i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s3 }; // s3-1=>s3, pop s3
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i=i+1; ram[i] = { `op_add_i, 6'd1, `P, `P, `s0, `s3 }; // s3+1=>s3, pop both
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// s/b one push over the line
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i=i+1; ram[i] = { op_cpy, `_, `_, `s2, `s1 }; // s2=>s1
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// check for a push error
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h910 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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i=i+1; ram[i] = { `op_shl_iu, -6'd8, `_, `P, `s0, `s0 }; // s0>>8=>s0, pop s0
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i=i+1; ram[i] = { `op_jmp_iglz, 5'd1, `_, `_, `s0, `s0 }; // (s0<>0) ? skip
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i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s3 }; // s3-1=>s3, pop s3
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i=i+1; ram[i] = { `op_add_i, 6'd1, `P, `P, `s0, `s3 }; // s3+1=>s3, pop both
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// empty s1
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h950 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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// check for no stack errors
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h910 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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i=i+1; ram[i] = { `op_jmp_iez, 5'd1, `_, `_, `s0, `s0 }; // (s0==0) ? skip
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i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s3 }; // s3-1=>s3, pop s3
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i=i+1; ram[i] = { `op_add_i, 6'd1, `P, `P, `s0, `s3 }; // s3+1=>s3, pop both
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// s/b one pop under the line
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i=i+1; ram[i] = { op_pop, `_, `P, `s0, `s1 }; // pop s1
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// check for a pop error
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h910 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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i=i+1; ram[i] = { `op_shl_i, 6'd24, `_, `P, `s0, `s0 }; // s0<<24=>s0, pop s0
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i=i+1; ram[i] = { `op_jmp_iglz, 5'd1, `_, `_, `s0, `s0 }; // (s0<>0) ? skip
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i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s3 }; // s3-1=>s3, pop s3
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i=i+1; ram[i] = { `op_add_i, 6'd1, `P, `P, `s0, `s3 }; // s3+1=>s3, pop both
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// s3=>s0, loop forever
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i=i+1; ram[i] = { op_cpy, `P, `P, `s3, `s0 }; // s3=>s0, pop both
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i=i+1; ram[i] = { `op_jmp_i, -5'h1, `_, `_, `s0, `s0 }; // loop forever
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// test stack clearing, result in s0
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// Correct functioning is s0 = 'd2 ('h2).
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//
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// s0 : final test result
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// s1 : test stack
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// s2 : sub addr
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// s3 : running test result, subroutine return address
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//
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// setup running test result:
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i='h200; ram[i] = { `op_byt_i, 8'd0, `_, `_, `s0, `s3 }; // 0=>s3
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// check for no stack errors
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h910 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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i=i+1; ram[i] = { `op_jmp_iez, 5'd1, `_, `_, `s0, `s0 }; // (s0==0) ? skip
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i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s3 }; // s3-1=>s3, pop s3 (Y)
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i=i+1; ram[i] = { `op_add_i, 6'd1, `P, `P, `s0, `s3 }; // s3+1=>s3, pop both
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// fill s1
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h940 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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// save s3
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'ha00 ; // addr
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i=i+1; ram[i] = { `op_wr_i, 4'd0, `P, `_, `s2, `s3 }; // write s3=>(s2+offset), pop s2
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// clear all stacks
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i=i+1; ram[i] = { op_cls, `_, `_, `s0, `s0 }; // clear stacks
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// restore s3
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'ha00 ; // addr
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i=i+1; ram[i] = { `op_rd_i, 4'd0, `P, `_, `s2, `s3 }; // read (s2+offset) => s3, pop s2
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// fill s1 again
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h940 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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// check for no stack errors
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i=i+1; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
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i=i+1; ram[i] = 16'h910 ; // addr
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i=i+1; ram[i] = { op_gsb, `P, `_, `s2, `s3 }; // gsb, pop s2 (addr)
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i=i+1; ram[i] = { `op_jmp_iez, 5'd1, `_, `_, `s0, `s0 }; // (s0==0) ? skip
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i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s3 }; // s3-1=>s3, pop s3
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i=i+1; ram[i] = { `op_add_i, 6'd1, `P, `P, `s0, `s3 }; // s3+1=>s3, pop both
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// s3=>s0, loop forever
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i=i+1; ram[i] = { op_cpy, `P, `P, `s3, `s0 }; // s3=>s0, pop both
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i=i+1; ram[i] = { `op_jmp_i, -5'h1, `_, `_, `s0, `s0 }; // loop forever
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/////////////////
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251 |
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// subroutines //
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252 |
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/////////////////
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253 |
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254 |
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255 |
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// sub : read & clear opcode errors for this thread => s0, return to (s3)
|
256 |
|
|
i='h900; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
|
257 |
|
|
i=i+1; ram[i] = REG_BASE_ADDR ; // reg base addr
|
258 |
|
|
i=i+1; ram[i] = { `op_rd_i, THRD_ID_ADDR, `_, `_, `s2, `s0 }; // read (s2+offset)=>s0
|
259 |
|
|
i=i+1; ram[i] = { op_shl_u, `_, `P, `s0, `s0 }; // 1<<s0=>s0, pop s0
|
260 |
|
|
i=i+1; ram[i] = { `op_rd_i, OP_ER_ADDR, `_, `_, `s2, `s3 }; // read (s2+offset)=>s3
|
261 |
|
|
i=i+1; ram[i] = { op_and, `P, `P, `s3, `s0 }; // s0&s3=>s0, pop both
|
262 |
|
|
i=i+1; ram[i] = { `op_wr_i, OP_ER_ADDR, `P, `_, `s2, `s0 }; // write s0=>(s2+offset), pop s2
|
263 |
|
|
i=i+1; ram[i] = { op_gto, `P, `_, `s3, `s0 }; // return to (s3), pop s3
|
264 |
|
|
|
265 |
|
|
|
266 |
|
|
// sub : read & clear stack errors for this thread => s0, return to (s3)
|
267 |
|
|
i='h910; ram[i] = { op_lit_u, `_, `_, `s0, `s2 }; // lit => s2
|
268 |
|
|
i=i+1; ram[i] = REG_BASE_ADDR ; // reg base addr
|
269 |
|
|
i=i+1; ram[i] = { `op_rd_i, THRD_ID_ADDR, `_, `_, `s2, `s0 }; // read (s2+offset)=>s0
|
270 |
|
|
i=i+1; ram[i] = { op_shl_u, `_, `P, `s0, `s0 }; // 1<<s0=>s0, pop s0
|
271 |
|
|
i=i+1; ram[i] = { op_cpy, `_, `_, `s0, `s3 }; // s0=>s3
|
272 |
|
|
i=i+1; ram[i] = { `op_shl_i, 6'd8, `_, `P, `s0, `s3 }; // s3<<8=>s3, pop s3
|
273 |
|
|
i=i+1; ram[i] = { op_or, `P, `P, `s3, `s0 }; // s0|s3=>s0, pop both
|
274 |
|
|
i=i+1; ram[i] = { `op_rd_i, STK_ER_ADDR, `_, `_, `s2, `s3 }; // read (s2+offset)=>s3
|
275 |
|
|
i=i+1; ram[i] = { op_and, `P, `P, `s3, `s0 }; // s0&s3=>s0, pop both
|
276 |
|
|
i=i+1; ram[i] = { `op_wr_i, STK_ER_ADDR, `P, `_, `s2, `s0 }; // write s0=>(s2+offset), pop s2
|
277 |
|
|
i=i+1; ram[i] = { op_gto, `P, `_, `s3, `s0 }; // return to (s3), pop s3
|
278 |
|
|
|
279 |
|
|
|
280 |
|
|
// sub : read 32 bit GPIO => s0, return to (s3)
|
281 |
|
|
i='h920; ram[i] = { op_lit_u, `_, `_, `s0, `s1 }; // lit => s1
|
282 |
|
|
i=i+1; ram[i] = REG_BASE_ADDR ; // reg base addr
|
283 |
|
|
i=i+1; ram[i] = { `op_rd_i, IO_LO_ADDR, `_, `_, `s1, `s0 }; // read (s1+offset) => s0
|
284 |
|
|
i=i+1; ram[i] = { `op_rd_ix, IO_HI_ADDR, `P, `P, `s1, `s0 }; // read (s1+offset) => s0, pop s1 & s0
|
285 |
|
|
i=i+1; ram[i] = { op_gto, `P, `_, `s3, `s0 }; // return, pop s3
|
286 |
|
|
|
287 |
|
|
|
288 |
|
|
// sub : write s0 => 32 bit GPIO, return to (s3)
|
289 |
|
|
i='h930; ram[i] = { op_lit_u, `_, `_, `s0, `s1 }; // lit => s1
|
290 |
|
|
i=i+1; ram[i] = REG_BASE_ADDR ; // reg base addr
|
291 |
|
|
i=i+1; ram[i] = { `op_wr_i, IO_LO_ADDR, `_, `_, `s1, `s0 }; // write s0 => (s1+offset)
|
292 |
|
|
i=i+1; ram[i] = { `op_wr_ix, IO_HI_ADDR, `P, `_, `s1, `s0 }; // write s0 => (s1+offset), pop s1
|
293 |
|
|
i=i+1; ram[i] = { op_gto, `P, `_, `s3, `s0 }; // return, pop s3
|
294 |
|
|
|
295 |
|
|
// sub : loop until empty s1 is full, return to (s3)
|
296 |
|
|
// loop setup:
|
297 |
|
|
i='h940; ram[i] = { `op_byt_i, 8'd32, `_, `_, `s0, `s2 }; // 32=>s2
|
298 |
|
|
// loop
|
299 |
|
|
i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s2 }; // s2--=>s2, pop s2
|
300 |
|
|
i=i+1; ram[i] = { op_cpy, `_, `_, `s2, `s1 }; // s2=>s1
|
301 |
|
|
i=i+1; ram[i] = { `op_jmp_igz, -5'd3, `_, `_, `s0, `s2 }; // (s2>0) ? do again
|
302 |
|
|
i=i+1; ram[i] = { op_gto, `P, `P, `s3, `s2 }; // return, pop s3 & s2
|
303 |
|
|
|
304 |
|
|
// sub : loop until full s1 is empty, return to (s3)
|
305 |
|
|
// loop setup:
|
306 |
|
|
i='h950; ram[i] = { `op_byt_i, 8'd32, `_, `_, `s0, `s2 }; // 32=>s2
|
307 |
|
|
// loop
|
308 |
|
|
i=i+1; ram[i] = { `op_add_i, -6'd1, `_, `P, `s0, `s2 }; // s2+1=>s2, pop s2
|
309 |
|
|
i=i+1; ram[i] = { op_pop, `_, `P, `s0, `s1 }; // pop s1
|
310 |
|
|
i=i+1; ram[i] = { `op_jmp_igz, -5'd3, `_, `_, `s0, `s2 }; // (s2>0) ? do again
|
311 |
|
|
i=i+1; ram[i] = { op_gto, `P, `P, `s3, `s2 }; // return, pop s3 & s2
|
312 |
|
|
|
313 |
|
|
|
314 |
|
|
end
|