diff --git a/.gitignore b/.gitignore
index 8284932..1ccbce1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -61,6 +61,11 @@ impact*
 *.asc
 *.onl
 
+# Test
+*.vcd
+*.actual
+*.expected
+
 # binary files
 *.gb
 
diff --git a/doc/control_unit.ods b/doc/control_unit.ods
index 1d72287..c64e646 100644
Binary files a/doc/control_unit.ods and b/doc/control_unit.ods differ
diff --git a/rtl/alu.v b/rtl/alu.v
index 2cd78b0..01748cb 100644
--- a/rtl/alu.v
+++ b/rtl/alu.v
@@ -102,7 +102,7 @@ module alu(
                     ~({1'b0, alu_b[7:4]}) +
                     {4'b0, ~result_low[4]};
                 alu_flags_out[F_C] = result_high[4];
-                alu_result = (alu_op == OP_CP) ? (alu_b[7:0]) : {result_high[3:0], result_low[3:0]};
+                alu_result = (alu_op == OP_CP) ? (alu_a[7:0]) : {result_high[3:0], result_low[3:0]};
                 alu_flags_out[F_Z] = ({result_high[3:0], result_low[3:0]} == 8'd0) ? 1'b1 : 1'b0;
             end
             OP_AND: begin
diff --git a/rtl/control.v b/rtl/control.v
index 275045c..53937d6 100644
--- a/rtl/control.v
+++ b/rtl/control.v
@@ -200,6 +200,22 @@ module control(
                     // RETI
                     ime_clear = 1'b1;
                 end
+                else if ((opcode == 8'h07) || 
+                        (opcode == 8'h17) || 
+                        (opcode == 8'h0F) || 
+                        (opcode == 8'h1F)) begin
+                    flags_pattern = 2'b10;
+                end
+                else if ((opcode == 8'hC7) ||
+                        (opcode == 8'hD7) ||
+                        (opcode == 8'hE7) ||
+                        (opcode == 8'hF7) ||
+                        (opcode == 8'hCF) ||
+                        (opcode == 8'hEF) ||
+                        (opcode == 8'hDF) ||
+                        (opcode == 8'hFF)) begin
+                    //bus_op = 2'b10;
+                end
                 else if ((opcode == 8'h04) ||
                         (opcode == 8'h14) ||
                         (opcode == 8'h24) ||
@@ -229,8 +245,15 @@ module control(
                         (opcode == 8'h9B) ||
                         (opcode == 8'h9C) ||
                         (opcode == 8'h9D) ||
-                        (opcode == 8'h9F)) begin
-                    // SUB
+                        (opcode == 8'h9F) ||
+                        (opcode == 8'hB8) ||
+                        (opcode == 8'hB9) ||
+                        (opcode == 8'hBA) ||
+                        (opcode == 8'hBB) ||
+                        (opcode == 8'hBC) ||
+                        (opcode == 8'hBD) ||
+                        (opcode == 8'hBF)) begin
+                    // SUB, CP
                     alu_src_xchg = 1'b1;
                 end
                 else if ((opcode == 8'h86) ||
@@ -436,8 +459,8 @@ module control(
                         rf_wr_sel = 3'b111;
                         rf_rd_sel = 3'b101;
                     end
-                    else if ((opcode == 8'h96) || (opcode == 8'h9E) || (opcode == 8'hD6) || (opcode == 8'hDE)) begin
-                        // SUB [HL] or SUB n
+                    else if ((opcode == 8'h96) || (opcode == 8'h9E) || (opcode == 8'hD6) || (opcode == 8'hDE) || (opcode == 8'hBE) || (opcode == 8'hFE)) begin
+                        // SUB [HL], SUB n, CP [HL], CP n
                         alu_src_xchg = 1;
                     end
                     else if (opcode == 8'hCB) begin
@@ -536,6 +559,7 @@ module control(
                     pc_src = 2'b01;
                     pc_we = 1'b1;
                     bus_op = 2'b10;
+                    ct_op = 2'b00;
                     next = 1'b1;
                 end
                 else if (((opcode == 8'hC4) && (!f_z)) ||    // CALL NZ
diff --git a/rtl/ppu.v b/rtl/ppu.v
index baa9557..b65b371 100644
--- a/rtl/ppu.v
+++ b/rtl/ppu.v
@@ -330,7 +330,7 @@ module ppu(
     // Data that will be pushed into pixel FIFO
     // Organized in pixels
     reg [31:0] current_fetch_result;
-    always@(current_tile_data_1, current_tile_data_0) begin
+    always@(*) begin
         for (i = 0; i < 8; i = i + 1) begin
             current_fetch_result[i*4+3] = current_tile_data_1[i];
             current_fetch_result[i*4+2] = current_tile_data_0[i];
@@ -359,7 +359,7 @@ module ppu(
     // Cascade mux used to implement the searching of next id would be triggered
     reg [3:0] obj_trigger_id_from[0:10];
     reg [3:0] obj_trigger_id_next;
-    always@(h_pix_obj, obj_trigger_id) begin
+    always@(*) begin
         obj_trigger_id_from[10] = OBJ_TRIGGER_NOT_FOUND; // There is no more after the 10th
         for (i = 9; i >= 0; i = i - 1) begin
             obj_trigger_id_from[i] = 
@@ -553,7 +553,7 @@ module ppu(
     end
     
     reg [31:0] half_merge_result;
-    always @(current_fetch_result, pf_data) begin
+    always @(*) begin
         for (i = 0; i < 8; i = i + 1) begin
             if ((pf_data[32+i*4+1] == PPU_PAL_BG[1])&&(pf_data[32+i*4+0] == PPU_PAL_BG[0])) begin
                 half_merge_result[i*4+3] = current_fetch_result[i*4+3];