diff --git a/BizHawk.Emulation.Cores/CPUs/LR35902/Execute.cs b/BizHawk.Emulation.Cores/CPUs/LR35902/Execute.cs
index d549963f60..2d26819a9d 100644
--- a/BizHawk.Emulation.Cores/CPUs/LR35902/Execute.cs
+++ b/BizHawk.Emulation.Cores/CPUs/LR35902/Execute.cs
@@ -562,8 +562,16 @@ namespace BizHawk.Emulation.Cores.Components.LR35902
 			// reset
 			instr_table[256 * 60 * 2] = IDLE;
 			instr_table[256 * 60 * 2 + 1] = IDLE;
-			instr_table[256 * 60 * 2 + 2] = HALT_CHK;
-			instr_table[256 * 60 * 2 + 3] = OP;
+			instr_table[256 * 60 * 2 + 2] = IDLE;
+			instr_table[256 * 60 * 2 + 3] = IDLE;
+			instr_table[256 * 60 * 2 + 4] = IDLE;
+			instr_table[256 * 60 * 2 + 5] = IDLE;
+			instr_table[256 * 60 * 2 + 6] = IDLE;
+			instr_table[256 * 60 * 2 + 7] = IDLE;
+			instr_table[256 * 60 * 2 + 8] = IDLE;
+			instr_table[256 * 60 * 2 + 9] = IDLE;
+			instr_table[256 * 60 * 2 + 10] = HALT_CHK;
+			instr_table[256 * 60 * 2 + 11] = OP;
 
 			// halt loop
 			instr_table[256 * 60 * 2 + 60] = IDLE;
diff --git a/BizHawk.Emulation.Cores/CPUs/LR35902/LR35902.cs b/BizHawk.Emulation.Cores/CPUs/LR35902/LR35902.cs
index ef62f3a6fb..ef7f03ab72 100644
--- a/BizHawk.Emulation.Cores/CPUs/LR35902/LR35902.cs
+++ b/BizHawk.Emulation.Cores/CPUs/LR35902/LR35902.cs
@@ -77,7 +77,7 @@ namespace BizHawk.Emulation.Cores.Components.LR35902
 			ResetRegisters();
 			ResetInterrupts();
 			BuildInstructionTable();
-			TotalExecutedCycles = 8;
+			TotalExecutedCycles = 0;
 			stop_check = false;
 			instr_pntr = 256 * 60 * 2; // point to reset
 			stopped = jammed = halted = FlagI = false;
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/SerialPort.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/SerialPort.cs
index 80495a8e07..62aac56059 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/SerialPort.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/SerialPort.cs
@@ -1,5 +1,6 @@
 using BizHawk.Common.NumberExtensions;
 using BizHawk.Common;
+using System;
 
 namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 {
@@ -48,12 +49,13 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 							if (((value & 2) > 0) && Core.GBC_compat)
 							{
 								clk_rate = 16;
+								serial_clock = (15 - (int)(Core.cpu.TotalExecutedCycles % 16)) + 1;
 							}
 							else
 							{
 								clk_rate = 512;
-							}						
-							serial_clock = clk_rate;
+								serial_clock = (511 - (int)(Core.cpu.TotalExecutedCycles % 512)) + 1;
+							}
 							can_pulse = true;
 						}
 						else
@@ -70,12 +72,13 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 							if (((value & 2) > 0) && Core.GBC_compat)
 							{
 								clk_rate = 16;
+								serial_clock = (15 - (int)(Core.cpu.TotalExecutedCycles % 16)) + 1;
 							}
 							else
 							{
 								clk_rate = 512;
-							}
-							serial_clock = clk_rate;
+								serial_clock = (511 - (int)(Core.cpu.TotalExecutedCycles % 512)) + 1;
+							}					
 							can_pulse = true;
 						}
 						else
diff --git a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/Timer.cs b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/Timer.cs
index 666cebdeb5..65fdc112d8 100644
--- a/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/Timer.cs
+++ b/BizHawk.Emulation.Cores/Consoles/Nintendo/GBHawk/Timer.cs
@@ -139,7 +139,7 @@ namespace BizHawk.Emulation.Cores.Nintendo.GBHawk
 
 		public void Reset()
 		{
-			divider_reg = 8; // probably always 8 but not confirmed for GB as far as I know
+			divider_reg = 0;
 			timer_reload = 0;
 			timer = 0;
 			timer_old = 0;