mirror of
https://github.com/sxpert/hp-saturn
synced 2024-12-27 09:58:16 +01:00
implement CONFIG and RTN* (0[0-3])
This commit is contained in:
parent
9168cbc1a2
commit
28483afe9a
7 changed files with 128 additions and 34 deletions
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@ -167,7 +167,7 @@ always @(posedge i_clk) begin
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end
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end
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`ifdef SIM
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`ifdef SIM
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if (cycle_ctr == 110) begin
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if (cycle_ctr == 130) begin
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bus_halt <= 1'b1;
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bus_halt <= 1'b1;
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$display("BUS %0d: [%d] enough cycles for now", phase, cycle_ctr);
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$display("BUS %0d: [%d] enough cycles for now", phase, cycle_ctr);
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end
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end
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@ -91,6 +91,7 @@ saturn_control_unit control_unit (
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/* debugger interface */
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/* debugger interface */
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.o_current_pc (ctrl_current_pc),
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.o_current_pc (ctrl_current_pc),
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.o_reg_alu_mode (ctrl_reg_alu_mode),
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.o_reg_alu_mode (ctrl_reg_alu_mode),
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.o_reg_carry (ctrl_reg_carry),
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.o_reg_hst (ctrl_reg_hst),
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.o_reg_hst (ctrl_reg_hst),
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.o_reg_st (ctrl_reg_st),
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.o_reg_st (ctrl_reg_st),
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.o_reg_p (ctrl_reg_p),
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.o_reg_p (ctrl_reg_p),
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@ -121,6 +122,7 @@ wire [0:0] ctrl_unit_no_read;
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/* debugger insterface */
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/* debugger insterface */
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wire [19:0] ctrl_current_pc;
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wire [19:0] ctrl_current_pc;
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wire [0:0] ctrl_reg_alu_mode;
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wire [0:0] ctrl_reg_alu_mode;
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wire [0:0] ctrl_reg_carry;
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wire [3:0] ctrl_reg_hst;
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wire [3:0] ctrl_reg_hst;
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wire [15:0] ctrl_reg_st;
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wire [15:0] ctrl_reg_st;
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wire [3:0] ctrl_reg_p;
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wire [3:0] ctrl_reg_p;
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@ -158,6 +160,7 @@ saturn_debugger debugger (
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/* debugger interface */
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/* debugger interface */
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.i_current_pc (ctrl_current_pc),
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.i_current_pc (ctrl_current_pc),
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.i_reg_alu_mode (ctrl_reg_alu_mode),
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.i_reg_alu_mode (ctrl_reg_alu_mode),
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.i_reg_carry (ctrl_reg_carry),
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.i_reg_hst (ctrl_reg_hst),
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.i_reg_hst (ctrl_reg_hst),
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.i_reg_st (ctrl_reg_st),
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.i_reg_st (ctrl_reg_st),
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.i_reg_p (ctrl_reg_p),
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.i_reg_p (ctrl_reg_p),
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@ -46,6 +46,7 @@ module saturn_control_unit (
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o_current_pc,
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o_current_pc,
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o_reg_alu_mode,
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o_reg_alu_mode,
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o_reg_carry,
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o_reg_p,
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o_reg_p,
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o_reg_hst,
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o_reg_hst,
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o_reg_st,
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o_reg_st,
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@ -91,7 +92,7 @@ assign o_error = control_unit_error || dec_error;
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output wire [19:0] o_current_pc;
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output wire [19:0] o_current_pc;
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output wire [0:0] o_reg_alu_mode;
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output wire [0:0] o_reg_alu_mode;
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assign o_reg_alu_mode = reg_alu_mode;
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output wire [0:0] o_reg_carry;
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output wire [3:0] o_reg_p;
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output wire [3:0] o_reg_p;
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output wire [3:0] o_reg_hst;
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output wire [3:0] o_reg_hst;
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output wire [15:0] o_reg_st;
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output wire [15:0] o_reg_st;
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@ -114,6 +115,8 @@ output wire [0:0] o_instr_decoded;
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output wire [0:0] o_instr_execute;
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output wire [0:0] o_instr_execute;
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assign o_current_pc = reg_PC;
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assign o_current_pc = reg_PC;
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assign o_reg_alu_mode = reg_alu_mode;
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assign o_reg_carry = reg_CARRY;
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assign o_reg_p = reg_P;
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assign o_reg_p = reg_P;
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assign o_reg_hst = reg_HST;
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assign o_reg_hst = reg_HST;
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assign o_reg_st = reg_ST;
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assign o_reg_st = reg_ST;
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@ -157,6 +160,7 @@ saturn_inst_decoder instruction_decoder(
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.o_alu_opcode (dec_alu_opcode),
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.o_alu_opcode (dec_alu_opcode),
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.o_jump_length (dec_jump_length),
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.o_jump_length (dec_jump_length),
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.o_block_0x (dec_block_0x),
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.o_instr_type (dec_instr_type),
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.o_instr_type (dec_instr_type),
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.o_push_pc (dec_push_pc),
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.o_push_pc (dec_push_pc),
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@ -175,6 +179,8 @@ wire [3:0] dec_alu_imm_value;
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wire [4:0] dec_alu_opcode;
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wire [4:0] dec_alu_opcode;
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wire [2:0] dec_jump_length;
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wire [2:0] dec_jump_length;
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/* this is necessary to identify possible RTN in time */
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wire [0:0] dec_block_0x;
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wire [3:0] dec_instr_type;
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wire [3:0] dec_instr_type;
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wire [0:0] dec_push_pc;
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wire [0:0] dec_push_pc;
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@ -189,6 +195,7 @@ wire [0:0] dec_error;
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wire [0:0] inst_alu = (dec_instr_type == `INSTR_TYPE_ALU);
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wire [0:0] inst_alu = (dec_instr_type == `INSTR_TYPE_ALU);
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wire [0:0] inst_jump = (dec_instr_type == `INSTR_TYPE_JUMP);
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wire [0:0] inst_jump = (dec_instr_type == `INSTR_TYPE_JUMP);
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wire [0:0] inst_rtn = (dec_instr_type == `INSTR_TYPE_RTN);
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wire [0:0] reg_dest_c = (dec_alu_reg_dest == `ALU_REG_C);
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wire [0:0] reg_dest_c = (dec_alu_reg_dest == `ALU_REG_C);
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wire [0:0] reg_dest_hst = (dec_alu_reg_dest == `ALU_REG_HST);
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wire [0:0] reg_dest_hst = (dec_alu_reg_dest == `ALU_REG_HST);
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@ -236,7 +243,9 @@ saturn_regs_pc_rstk regs_pc_rstk (
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.i_nibble (i_nibble),
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.i_nibble (i_nibble),
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.i_jump_instr (inst_jump),
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.i_jump_instr (inst_jump),
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.i_jump_length (dec_jump_length),
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.i_jump_length (dec_jump_length),
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.i_block_0x (dec_block_0x),
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.i_push_pc (dec_push_pc),
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.i_push_pc (dec_push_pc),
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.i_rtn_instr (inst_rtn),
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.o_current_pc (reg_PC),
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.o_current_pc (reg_PC),
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.o_reload_pc (reload_PC),
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.o_reload_pc (reload_PC),
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@ -254,6 +263,7 @@ saturn_regs_pc_rstk regs_pc_rstk (
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reg [0:0] reg_alu_mode;
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reg [0:0] reg_alu_mode;
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reg [0:0] reg_CARRY;
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reg [3:0] reg_C[0:15];
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reg [3:0] reg_C[0:15];
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reg [3:0] reg_HST;
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reg [3:0] reg_HST;
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reg [15:0] reg_ST;
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reg [15:0] reg_ST;
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@ -284,6 +294,7 @@ reg [4:0] bus_program[0:31];
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reg [4:0] bus_prog_addr;
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reg [4:0] bus_prog_addr;
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reg [2:0] addr_nibble_ptr;
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reg [2:0] addr_nibble_ptr;
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reg [0:0] load_pc_loop;
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reg [0:0] load_pc_loop;
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reg [0:0] send_reg_C_A;
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reg [0:0] send_pc_read;
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reg [0:0] send_pc_read;
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wire [3:0] reg_PC_nibble = reg_PC[addr_nibble_ptr*4+:4];
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wire [3:0] reg_PC_nibble = reg_PC[addr_nibble_ptr*4+:4];
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@ -301,9 +312,12 @@ initial begin
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bus_prog_addr = 5'd0;
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bus_prog_addr = 5'd0;
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addr_nibble_ptr = 3'd0;
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addr_nibble_ptr = 3'd0;
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load_pc_loop = 1'b0;
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load_pc_loop = 1'b0;
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send_reg_C_A = 1'b0;
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send_pc_read = 1'b0;
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/* registers */
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/* registers */
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reg_alu_mode = 1'b0;
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reg_alu_mode = 1'b0;
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reg_CARRY = 1'b0;
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reg_HST = 4'b0;
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reg_HST = 4'b0;
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reg_ST = 16'b0;
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reg_ST = 16'b0;
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reg_P = 4'b0;
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reg_P = 4'b0;
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@ -448,6 +462,17 @@ always @(posedge i_clk) begin
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reg_alu_mode <= dec_alu_imm_value[0];
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reg_alu_mode <= dec_alu_imm_value[0];
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end
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end
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`INSTR_TYPE_JUMP: begin end
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`INSTR_TYPE_JUMP: begin end
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`INSTR_TYPE_RTN:
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begin
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case (dec_alu_opcode)
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`ALU_OP_SET_CRY: reg_CARRY <= o_alu_imm_value[0];
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default:
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begin
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$display("CTRL %0d: [%d] alu_opcode for RTN %0d", i_phase, i_cycle_ctr, dec_alu_opcode);
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control_unit_error <= 1'b1;
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end
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endcase
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end
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`INSTR_TYPE_LOAD:
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`INSTR_TYPE_LOAD:
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begin
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begin
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case (dec_alu_reg_dest)
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case (dec_alu_reg_dest)
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@ -457,9 +482,21 @@ always @(posedge i_clk) begin
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$display("CTRL %0d: [%d] C[%2d] <= %h", i_phase, i_cycle_ctr, dec_alu_ptr_begin, dec_alu_imm_value);
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$display("CTRL %0d: [%d] C[%2d] <= %h", i_phase, i_cycle_ctr, dec_alu_ptr_begin, dec_alu_imm_value);
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reg_C[dec_alu_ptr_begin] <= dec_alu_imm_value;
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reg_C[dec_alu_ptr_begin] <= dec_alu_imm_value;
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end
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end
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default: $display("CTRL %0d: [%d] unsupported register for load %0d", i_phase, i_cycle_ctr, dec_alu_reg_dest);
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default:
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begin
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$display("CTRL %0d: [%d] unsupported register for load %0d", i_phase, i_cycle_ctr, dec_alu_reg_dest);
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control_unit_error <= 1'b1;
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end
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endcase
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endcase
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end
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end
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`INSTR_TYPE_CONFIG:
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begin
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$display("CTRL %0d: [%d] exec : CONFIG", i_phase, i_cycle_ctr);
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bus_program[bus_prog_addr] <= {1'b1, `BUSCMD_CONFIGURE };
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bus_prog_addr <= bus_prog_addr + 5'd1;
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addr_nibble_ptr <= 3'b0;
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send_reg_C_A <= 1'b1;
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end
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`INSTR_TYPE_RESET:
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`INSTR_TYPE_RESET:
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begin
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begin
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$display("CTRL %0d: [%d] exec : RESET", i_phase, i_cycle_ctr);
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$display("CTRL %0d: [%d] exec : RESET", i_phase, i_cycle_ctr);
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@ -470,10 +507,29 @@ always @(posedge i_clk) begin
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default:
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default:
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begin
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begin
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$display("CTRL %0d: [%d] unsupported instruction", i_phase, i_cycle_ctr);
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$display("CTRL %0d: [%d] unsupported instruction", i_phase, i_cycle_ctr);
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control_unit_error <= 1'b1;
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end
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end
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endcase
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endcase
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end
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end
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/*
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* send C(A)
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* used for CONFIG and UNCNFG
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*/
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if (send_reg_C_A) begin
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bus_program[bus_prog_addr] <= { 1'b0, reg_C[{1'b0, addr_nibble_ptr}]};
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addr_nibble_ptr <= addr_nibble_ptr + 3'd1;
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bus_prog_addr <= bus_prog_addr + 5'd1;
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if (addr_nibble_ptr == 3'd4) begin
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addr_nibble_ptr <= 3'd0;
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send_pc_read <= 1'b1;
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send_reg_C_A <= 1'b0;
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end
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end
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/*
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* sends the PC_READ command to restore devices after some other bus command
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*/
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if (send_pc_read) begin
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if (send_pc_read) begin
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$display("CTRL %0d: [%d] exec : RESET - send PC_READ", i_phase, i_cycle_ctr);
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$display("CTRL %0d: [%d] exec : RESET - send PC_READ", i_phase, i_cycle_ctr);
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bus_program[bus_prog_addr] <= {1'b1, `BUSCMD_PC_READ };
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bus_program[bus_prog_addr] <= {1'b1, `BUSCMD_PC_READ };
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@ -493,9 +549,12 @@ always @(posedge i_clk) begin
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bus_prog_addr <= 5'd0;
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bus_prog_addr <= 5'd0;
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addr_nibble_ptr <= 3'd0;
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addr_nibble_ptr <= 3'd0;
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load_pc_loop <= 1'b0;
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load_pc_loop <= 1'b0;
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send_reg_C_A <= 1'b0;
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send_pc_read <= 1'b0;
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/* registers */
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/* registers */
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reg_alu_mode <= 1'b0;
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reg_alu_mode <= 1'b0;
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reg_CARRY <= 1'b0;
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reg_HST <= 4'b0;
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reg_HST <= 4'b0;
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reg_ST <= 16'b0;
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reg_ST <= 16'b0;
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reg_P <= 4'b0;
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reg_P <= 4'b0;
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@ -36,6 +36,7 @@ module saturn_debugger (
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/* interface from the control unit */
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/* interface from the control unit */
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i_current_pc,
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i_current_pc,
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i_reg_alu_mode,
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i_reg_alu_mode,
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i_reg_carry,
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i_reg_hst,
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i_reg_hst,
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i_reg_st,
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i_reg_st,
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i_reg_p,
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i_reg_p,
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@ -81,6 +82,7 @@ output reg [0:0] o_debug_cycle;
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/* inteface from the control unit */
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/* inteface from the control unit */
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input wire [19:0] i_current_pc;
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input wire [19:0] i_current_pc;
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input wire [0:0] i_reg_alu_mode;
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input wire [0:0] i_reg_alu_mode;
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input wire [0:0] i_reg_carry;
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input wire [3:0] i_reg_hst;
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input wire [3:0] i_reg_hst;
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input wire [15:0] i_reg_st;
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input wire [15:0] i_reg_st;
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input wire [3:0] i_reg_p;
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input wire [3:0] i_reg_p;
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@ -135,8 +137,6 @@ reg [6:0] registers_state;
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reg [5:0] registers_reg_ptr;
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reg [5:0] registers_reg_ptr;
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reg [0:0] registers_done;
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reg [0:0] registers_done;
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reg [0:0] carry;
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initial begin
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initial begin
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o_debug_cycle = 1'b0;
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o_debug_cycle = 1'b0;
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counter = 9'd0;
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counter = 9'd0;
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@ -164,7 +164,6 @@ initial begin
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registers_done = 1'b0;
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registers_done = 1'b0;
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o_char_valid = 1'b0;
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o_char_valid = 1'b0;
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o_char_send = 1'b0;
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o_char_send = 1'b0;
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carry = 1'b1;
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end
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end
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/**************************************************************************************************
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/**************************************************************************************************
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@ -243,7 +242,7 @@ always @(posedge i_clk) begin
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6'd4: registers_str[registers_ctr] <= "y";
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6'd4: registers_str[registers_ctr] <= "y";
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6'd5: registers_str[registers_ctr] <= ":";
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6'd5: registers_str[registers_ctr] <= ":";
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6'd6: registers_str[registers_ctr] <= " ";
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6'd6: registers_str[registers_ctr] <= " ";
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6'd7: registers_str[registers_ctr] <= hex[{3'b000,carry}];
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6'd7: registers_str[registers_ctr] <= hex[{3'b000,i_reg_carry}];
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6'd8: registers_str[registers_ctr] <= " ";
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6'd8: registers_str[registers_ctr] <= " ";
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endcase
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endcase
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registers_reg_ptr <= registers_reg_ptr + 6'd1;
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registers_reg_ptr <= registers_reg_ptr + 6'd1;
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@ -538,36 +537,15 @@ always @(posedge i_clk) begin
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end
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end
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end
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end
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/*
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* dumps nibbles read from the bus
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*/
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if (i_bus_read_valid) begin
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if (i_bus_read_valid) begin
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||||||
o_char_send <= ~o_char_send;
|
o_char_send <= ~o_char_send;
|
||||||
o_char_to_send <= hex[i_bus_nibble_in];
|
o_char_to_send <= hex[i_bus_nibble_in];
|
||||||
o_char_valid <= 1'b1;
|
o_char_valid <= 1'b1;
|
||||||
end
|
end
|
||||||
|
|
||||||
if (i_clk_en && i_bus_busy) begin
|
|
||||||
o_char_send <= ~o_char_send;
|
|
||||||
case (i_phase)
|
|
||||||
2'b00: o_char_to_send <= "!";
|
|
||||||
2'b01: o_char_to_send <= "@";
|
|
||||||
2'b10: o_char_to_send <= "#";
|
|
||||||
2'b11: o_char_to_send <= "$";
|
|
||||||
endcase
|
|
||||||
if (i_instr_decoded) o_char_to_send <= "=";
|
|
||||||
o_char_valid <= 1'b1;
|
|
||||||
end
|
|
||||||
|
|
||||||
if (i_clk_en && i_instr_execute && i_phases[3]) begin
|
|
||||||
o_char_send <= ~o_char_send;
|
|
||||||
o_char_to_send <= "^";
|
|
||||||
o_char_valid <= 1'b1;
|
|
||||||
end
|
|
||||||
|
|
||||||
if (i_clk_en && i_instr_decoded && i_phases[3]) begin
|
|
||||||
o_char_send <= ~o_char_send;
|
|
||||||
o_char_to_send <= "|";
|
|
||||||
o_char_valid <= 1'b1;
|
|
||||||
end
|
|
||||||
|
|
||||||
/* clear the char clock enable */
|
/* clear the char clock enable */
|
||||||
if (o_char_valid) begin
|
if (o_char_valid) begin
|
||||||
o_char_valid <= 1'b0;
|
o_char_valid <= 1'b0;
|
||||||
|
|
|
@ -47,6 +47,7 @@
|
||||||
`define ALU_OP_JMP_ABS5 20
|
`define ALU_OP_JMP_ABS5 20
|
||||||
`define ALU_OP_CLR_MASK 21
|
`define ALU_OP_CLR_MASK 21
|
||||||
|
|
||||||
|
`define ALU_OP_SET_CRY 28
|
||||||
`define ALU_OP_TEST_GO 30
|
`define ALU_OP_TEST_GO 30
|
||||||
`define ALU_OP_NOP 31
|
`define ALU_OP_NOP 31
|
||||||
|
|
||||||
|
@ -101,8 +102,11 @@
|
||||||
`define INSTR_TYPE_ALU 1
|
`define INSTR_TYPE_ALU 1
|
||||||
`define INSTR_TYPE_SET_MODE 2
|
`define INSTR_TYPE_SET_MODE 2
|
||||||
`define INSTR_TYPE_JUMP 3
|
`define INSTR_TYPE_JUMP 3
|
||||||
`define INSTR_TYPE_LOAD 4
|
`define INSTR_TYPE_RTN 4
|
||||||
`define INSTR_TYPE_RESET 5
|
`define INSTR_TYPE_LOAD 5
|
||||||
|
`define INSTR_TYPE_CONFIG 6
|
||||||
|
`define INSTR_TYPE_RESET 7
|
||||||
|
|
||||||
|
|
||||||
`define INSTR_TYPE_NONE 15
|
`define INSTR_TYPE_NONE 15
|
||||||
|
|
||||||
|
|
|
@ -47,6 +47,7 @@ module saturn_inst_decoder (
|
||||||
o_alu_opcode,
|
o_alu_opcode,
|
||||||
|
|
||||||
o_jump_length,
|
o_jump_length,
|
||||||
|
o_block_0x,
|
||||||
|
|
||||||
o_instr_type,
|
o_instr_type,
|
||||||
o_push_pc,
|
o_push_pc,
|
||||||
|
@ -82,6 +83,8 @@ output reg [3:0] o_alu_imm_value;
|
||||||
output reg [4:0] o_alu_opcode;
|
output reg [4:0] o_alu_opcode;
|
||||||
|
|
||||||
output reg [2:0] o_jump_length;
|
output reg [2:0] o_jump_length;
|
||||||
|
output wire [0:0] o_block_0x;
|
||||||
|
assign o_block_0x = block_0x;
|
||||||
|
|
||||||
output reg [3:0] o_instr_type;
|
output reg [3:0] o_instr_type;
|
||||||
output reg [0:0] o_push_pc;
|
output reg [0:0] o_push_pc;
|
||||||
|
@ -247,6 +250,16 @@ always @(posedge i_clk) begin
|
||||||
|
|
||||||
if (block_0x) begin
|
if (block_0x) begin
|
||||||
case (i_nibble)
|
case (i_nibble)
|
||||||
|
4'h2, 4'h3:
|
||||||
|
begin
|
||||||
|
$display("DECODER %0d: [%d] RTN%cC", i_phase, i_cycle_ctr, i_nibble[0]?"C":"S");
|
||||||
|
o_instr_type <= `INSTR_TYPE_RTN;
|
||||||
|
o_alu_imm_value <= {3'b000, !i_nibble[0]};
|
||||||
|
o_alu_opcode <= `ALU_OP_SET_CRY;
|
||||||
|
o_instr_decoded <= 1'b1;
|
||||||
|
o_instr_execute <= 1'b1;
|
||||||
|
decode_started <= 1'b0;
|
||||||
|
end
|
||||||
4'h4, 4'h5:
|
4'h4, 4'h5:
|
||||||
begin
|
begin
|
||||||
o_instr_type <= `INSTR_TYPE_SET_MODE;
|
o_instr_type <= `INSTR_TYPE_SET_MODE;
|
||||||
|
@ -323,6 +336,13 @@ always @(posedge i_clk) begin
|
||||||
|
|
||||||
if (block_80x) begin
|
if (block_80x) begin
|
||||||
case (i_nibble)
|
case (i_nibble)
|
||||||
|
4'h5: /* CONFIG */
|
||||||
|
begin
|
||||||
|
o_instr_type <= `INSTR_TYPE_CONFIG;
|
||||||
|
o_instr_decoded <= 1'b1;
|
||||||
|
o_instr_execute <= 1'b1;
|
||||||
|
decode_started <= 1'b0;
|
||||||
|
end
|
||||||
4'hA: /* RESET */
|
4'hA: /* RESET */
|
||||||
begin
|
begin
|
||||||
o_instr_type <= `INSTR_TYPE_RESET;
|
o_instr_type <= `INSTR_TYPE_RESET;
|
||||||
|
|
|
@ -33,7 +33,9 @@ module saturn_regs_pc_rstk (
|
||||||
i_nibble,
|
i_nibble,
|
||||||
i_jump_instr,
|
i_jump_instr,
|
||||||
i_jump_length,
|
i_jump_length,
|
||||||
|
i_block_0x,
|
||||||
i_push_pc,
|
i_push_pc,
|
||||||
|
i_rtn_instr,
|
||||||
|
|
||||||
o_current_pc,
|
o_current_pc,
|
||||||
o_reload_pc,
|
o_reload_pc,
|
||||||
|
@ -56,7 +58,9 @@ input wire [0:0] i_bus_busy;
|
||||||
input wire [3:0] i_nibble;
|
input wire [3:0] i_nibble;
|
||||||
input wire [0:0] i_jump_instr;
|
input wire [0:0] i_jump_instr;
|
||||||
input wire [2:0] i_jump_length;
|
input wire [2:0] i_jump_length;
|
||||||
|
input wire [0:0] i_block_0x;
|
||||||
input wire [0:0] i_push_pc;
|
input wire [0:0] i_push_pc;
|
||||||
|
input wire [0:0] i_rtn_instr;
|
||||||
|
|
||||||
output wire [19:0] o_current_pc;
|
output wire [19:0] o_current_pc;
|
||||||
output reg [0:0] o_reload_pc;
|
output reg [0:0] o_reload_pc;
|
||||||
|
@ -196,6 +200,32 @@ always @(posedge i_clk) begin
|
||||||
o_reload_pc <= 1'b0;
|
o_reload_pc <= 1'b0;
|
||||||
end
|
end
|
||||||
|
|
||||||
|
/*
|
||||||
|
* RTN instruction
|
||||||
|
*/
|
||||||
|
|
||||||
|
/* this happens at the same time in the decoder */
|
||||||
|
if (i_phases[2] && i_block_0x && (i_nibble[3:2] == 2'b00)) begin
|
||||||
|
/* this is an RTN */
|
||||||
|
$write("PC_RSTK %0d: [%d] RTN", i_phase, i_cycle_ctr);
|
||||||
|
case (i_nibble)
|
||||||
|
4'h0: $display("SXM");
|
||||||
|
4'h2: $display("SC");
|
||||||
|
4'h3: $display("CC");
|
||||||
|
default: begin end
|
||||||
|
endcase
|
||||||
|
o_reload_pc <= 1'b1;
|
||||||
|
end
|
||||||
|
|
||||||
|
if (i_phases[3] && i_rtn_instr) begin
|
||||||
|
$display("PC_RSTK %0d: [%d] execute RTN back to %5h", i_phase, i_cycle_ctr, reg_RSTK[reg_rstk_ptr]);
|
||||||
|
reg_PC <= reg_RSTK[reg_rstk_ptr];
|
||||||
|
reg_RSTK[reg_rstk_ptr] <= 20'h00000;
|
||||||
|
reg_rstk_ptr <= (reg_rstk_ptr - 3'd1) & 3'd7;
|
||||||
|
/* o_reload_pc was set in advance above */
|
||||||
|
o_reload_pc <= 1'b0;
|
||||||
|
end
|
||||||
|
|
||||||
end
|
end
|
||||||
|
|
||||||
// if (i_phases[0] && i_clk_en) begin
|
// if (i_phases[0] && i_clk_en) begin
|
||||||
|
|
Loading…
Reference in a new issue