mirror of
https://github.com/sxpert/hp-saturn
synced 2024-11-16 19:50:19 +01:00
33 lines
935 B
Verilog
33 lines
935 B
Verilog
/******************************************************************************
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* 6xxx GOTO xxx
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*
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*
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*/
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`include "decstates.v"
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`include "bus_commands.v"
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`DEC_GOTO: begin
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//$display("DEC_GOTO : nibble %h", nibble);
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jump_base <= PC;
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jump_offset <= 0;
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t_cnt <= 2;
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t_ctr <= 1;
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jump_offset[3:0] <= nibble;
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decstate <= `DEC_GOTO_LOOP;
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end
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`DEC_GOTO_LOOP: begin
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//$display("jump_base %h | t_cnt %d | t_ctr %d | jump_offset %h", jump_base, t_cnt, t_ctr, jump_offset);
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jump_offset[t_ctr*4+:4] <= nibble;
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if (t_ctr == t_cnt) begin
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new_PC <= jump_base + {8'h00, nibble, jump_offset[7:0]};
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next_cycle <= `BUSCMD_LOAD_PC;
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decstate <= `DEC_START;
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`ifdef SIM
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$display("%5h GOTO\t%3h\t=> %05h",
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inst_start_PC,
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{nibble, jump_offset[7:0]},
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jump_base + {8'h00, nibble, jump_offset[7:0]});
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`endif
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end else t_ctr <= t_ctr + 1;
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end
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