Cut 1 at ADD HL,...
authorJoshua Wise <joshua@rebirth.joshuawise.com>
Fri, 9 May 2008 09:34:07 +0000 (05:34 -0400)
committerJoshua Wise <joshua@rebirth.joshuawise.com>
Fri, 9 May 2008 09:34:07 +0000 (05:34 -0400)
GBZ80Core.v
Makefile
allinsns.v
insn_add_hl.v [new file with mode: 0644]
opcodes

index 29aab52..053df4a 100644 (file)
@@ -79,6 +79,7 @@
 `define INSN_BIT               9'b101xxxxxx
 `define INSN_RES               9'b110xxxxxx
 `define INSN_SET               9'b111xxxxxx
+`define INSN_ADD_HL            9'b000xx1001
 
 `define INSN_cc_NZ             2'b00
 `define INSN_cc_Z              2'b01
index 5e50da8..40ea542 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -8,7 +8,7 @@ VLOGS_ALL = $(VLOGS) insn_call-callcc.v insn_incdec16.v insn_jr-jrcc.v \
        CPUDCM.v insn_alu_a.v insn_halt.v insn_jp-jpcc.v insn_ld_hl_reg.v \
        insn_ld_reg_imm8.v insn_ldx_ahl.v insn_push_reg.v insn_vop_intr.v \
        insn_ldm8_a.v insn_ldm16_a.v insn_ldbcde_a.v insn_alu_ext.v \
-       insn_bit.v insn_two_byte.v insn_incdec_reg8.v
+       insn_bit.v insn_two_byte.v insn_incdec_reg8.v insn_add_hl.v
 
 all: CoreTop.svf
 
index 6c1c487..dfdf04f 100644 (file)
@@ -29,3 +29,4 @@
 `include "insn_two_byte.v"
 `include "insn_bit.v"
 `include "insn_alu_ext.v"
+`include "insn_add_hl.v"
diff --git a/insn_add_hl.v b/insn_add_hl.v
new file mode 100644 (file)
index 0000000..8ff25f4
--- /dev/null
@@ -0,0 +1,33 @@
+`ifdef EXECUTE
+       `INSN_ADD_HL: begin
+               case (cycle)
+               0:      case (opcode[5:4])
+                       `INSN_reg16_BC: {tmp,tmp2} <= `_BC;
+                       `INSN_reg16_DE: {tmp,tmp2} <= `_DE;
+                       `INSN_reg16_HL: {tmp,tmp2} <= `_HL;
+                       `INSN_reg16_SP: {tmp,tmp2} <= `_SP;
+                       endcase
+               1:      begin
+                               `EXEC_INC_PC
+                               `EXEC_NEWCYCLE
+                       end
+               endcase
+       end
+`endif
+
+`ifdef WRITEBACK
+       `INSN_ADD_HL: begin
+               case (cycle)
+               0:      {tmp,tmp2} <= `_HL + {tmp,tmp2};
+               1:      begin
+                               `_F <=  { /* Z */ `_F[7],
+                                         /* N */ 1'b0,
+                                         /* H */ (({`_HL} + {tmp,tmp2}) & 16'h1000) ? 1'b1 : 1'b0,
+                                         /* C */ (({1'b0,`_HL} + {1'b0,tmp,tmp2}) >> 16 == 1) ? 1'b1 : 1'b0,
+                                         `_F[3:0]
+                                       };
+                               `_HL <= {tmp, tmp2};
+                       end
+               endcase
+       end
+`endif
diff --git a/opcodes b/opcodes
index 09f68fb..451a6b6 100644 (file)
--- a/opcodes
+++ b/opcodes
@@ -8,11 +8,7 @@ imm16 = 16-bit immediate value
 
 bits         insn                 notes
 0000 1000    LD    16m16,SP      loads SP
-0000 1001    ADD   HL,   BC
 0001 0000    STOP
-0001 1001    ADD   HL,   DE
-0010 1001    ADD   HL,   HL
-0011 1001    ADD   HL,   SP
 0111 0110    HALT                 Danger! Helvetica!
 1100 1011    -     -     -        see two-byte opcodes below
 1110 1000    ADD   SP,   imm8
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