hp-saturn/opcodes/1[BF]nnnnn_D[01]_EQ_5n.v
2019-02-09 19:18:58 +01:00

50 lines
No EOL
1.2 KiB
Verilog

/******************************************************************************
*1bnnnnn DO=(5) nnnnn
*
*
*/
`include "decstates.v"
`DEC_D1_EQ_4N,
`DEC_D0_EQ_5N, `DEC_D1_EQ_5N: begin
case (decstate)
`DEC_D1_EQ_4N: t_cnt <= 3;
`DEC_D0_EQ_5N, `DEC_D1_EQ_5N: t_cnt <= 4;
endcase
t_ctr <= 1;
case (decstate)
`DEC_D0_EQ_5N: begin
D0[3:0] <= nb_in;
decstate <= `DEC_D0_EQ_LOOP;
end
`DEC_D1_EQ_4N, `DEC_D1_EQ_5N: begin
D1[3:0] <= nb_in;
decstate <= `DEC_D1_EQ_LOOP;
end
endcase
end
`DEC_D0_EQ_LOOP, `DEC_D1_EQ_LOOP: begin
if (decstate == `DEC_D0_EQ_LOOP)
D0[t_ctr*4+:4] <= nb_in;
else
D1[t_ctr*4+:4] <= nb_in;
if (t_ctr == t_cnt) begin
decstate <= `DEC_START;
`ifdef SIM
$write("%5h D%b=(%1d)\t%1h", inst_start_PC,
(decstate == `DEC_D0_EQ_LOOP)?1'b0:1'b1,
(t_cnt + 1), nb_in);
for(t_ctr = 0; t_ctr != t_cnt; t_ctr ++)
$write("%1h",
(decstate == `DEC_D0_EQ_LOOP)?
D0[(t_cnt - t_ctr - 4'h1)*4+:4]:
D1[(t_cnt - t_ctr - 4'h1)*4+:4]
);
$write("\n");
`endif
end else
t_ctr <= t_ctr + 1;
end