diff --git a/src/mame/drivers/agat.cpp b/src/mame/drivers/agat.cpp
index 6a899e085bd..4f7b20828b4 100644
--- a/src/mame/drivers/agat.cpp
+++ b/src/mame/drivers/agat.cpp
@@ -585,10 +585,24 @@ uint8_t agat_base_state::controller_strobe_r()
 
 void agat_base_state::controller_strobe_w(uint8_t data)
 {
-	m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_joy1x->read();
-	m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_joy1y->read();
-	m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_joy2x->read();
-	m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_joy2y->read();
+	// 555 monostable one-shot timers; a running timer cannot be restarted
+	if (machine().time().as_double() >= m_joystick_x1_time) 
+	{
+		m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_joy1x->read();
+	}
+	if (machine().time().as_double() >= m_joystick_y1_time) 
+	{
+		m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_joy1y->read();
+	}
+	if (machine().time().as_double() >= m_joystick_x2_time) 
+	{
+		m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_joy2x->read();
+	}
+	if (machine().time().as_double() >= m_joystick_y2_time) 
+	{
+		m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_joy2y->read();
+	}
+
 }
 
 uint8_t agat_base_state::c080_r(offs_t offset)
diff --git a/src/mame/drivers/apple2.cpp b/src/mame/drivers/apple2.cpp
index 21cc5fcfc00..d43eb3fa842 100644
--- a/src/mame/drivers/apple2.cpp
+++ b/src/mame/drivers/apple2.cpp
@@ -677,10 +677,24 @@ u8 apple2_state::controller_strobe_r()
 
 void apple2_state::controller_strobe_w(u8 data)
 {
-	m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl0_r();
-	m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl1_r();
-	m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl2_r();
-	m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl3_r();
+	// 558 monostable one-shot timers; a running timer cannot be restarted
+	if (machine().time().as_double() >= m_joystick_x1_time) 
+	{
+		m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl0_r();
+	}
+	if (machine().time().as_double() >= m_joystick_y1_time) 
+	{
+		m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl1_r();
+	}
+	if (machine().time().as_double() >= m_joystick_x2_time) 
+	{
+		m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl2_r();
+	}
+	if (machine().time().as_double() >= m_joystick_y2_time) 
+	{
+		m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl3_r();
+	}
+
 }
 
 u8 apple2_state::c080_r(offs_t offset)
diff --git a/src/mame/drivers/apple2e.cpp b/src/mame/drivers/apple2e.cpp
index da3b6038563..d0279537c2c 100644
--- a/src/mame/drivers/apple2e.cpp
+++ b/src/mame/drivers/apple2e.cpp
@@ -1903,10 +1903,23 @@ void apple2e_state::do_io(int offset, bool is_iic)
 				accel_normal_speed();
 			}
 
-			m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl0_r();
-			m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl1_r();
-			m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl2_r();
-			m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl3_r();
+			// 558 monostable one-shot timers; a running timer cannot be restarted
+			if (machine().time().as_double() >= m_joystick_x1_time) 
+			{
+				m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl0_r();
+			}
+			if (machine().time().as_double() >= m_joystick_y1_time) 
+			{
+				m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl1_r();
+			}
+			if (machine().time().as_double() >= m_joystick_x2_time) 
+			{
+				m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl2_r();
+			}
+			if (machine().time().as_double() >= m_joystick_y2_time) 
+			{
+				m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl3_r();
+			}
 			break;
 
 		default:
diff --git a/src/mame/drivers/apple2gs.cpp b/src/mame/drivers/apple2gs.cpp
index 1fc12562cd1..80f4588bcfe 100644
--- a/src/mame/drivers/apple2gs.cpp
+++ b/src/mame/drivers/apple2gs.cpp
@@ -2187,10 +2187,23 @@ void apple2gs_state::do_io(int offset)
 				accel_normal_speed();
 			}
 
-			m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl0_r();
-			m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl1_r();
-			m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl2_r();
-			m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl3_r();
+			// 558 monostable one-shot timers; a running timer cannot be restarted
+			if (machine().time().as_double() >= m_joystick_x1_time) 
+			{
+				m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl0_r();
+			}
+			if (machine().time().as_double() >= m_joystick_y1_time) 
+			{
+				m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl1_r();
+			}
+			if (machine().time().as_double() >= m_joystick_x2_time) 
+			{
+				m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl2_r();
+			}
+			if (machine().time().as_double() >= m_joystick_y2_time) 
+			{
+				m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl3_r();
+			}
 			break;
 
 		default:
@@ -2627,10 +2640,24 @@ u8 apple2gs_state::c000_r(offs_t offset)
 					accel_normal_speed();
 				}
 
-				m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl0_r();
-				m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl1_r();
-				m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl2_r();
-				m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl3_r();
+				// 558 monostable one-shot timers; a running timer cannot be restarted
+				if (machine().time().as_double() >= m_joystick_x1_time) 
+				{
+					m_joystick_x1_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl0_r();
+				}
+				if (machine().time().as_double() >= m_joystick_y1_time) 
+				{
+					m_joystick_y1_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl1_r();
+				}
+				if (machine().time().as_double() >= m_joystick_x2_time) 
+				{
+					m_joystick_x2_time = machine().time().as_double() + m_x_calibration * m_gameio->pdl2_r();
+				}
+				if (machine().time().as_double() >= m_joystick_y2_time) 
+				{
+					m_joystick_y2_time = machine().time().as_double() + m_y_calibration * m_gameio->pdl3_r();
+				}
+
 			}
 
 			return m_rom[offset + 0x3c000];