diff --git a/scripts/target/mame/arcade.lua b/scripts/target/mame/arcade.lua
index 44e7d5dd37e..7902a86ae4f 100644
--- a/scripts/target/mame/arcade.lua
+++ b/scripts/target/mame/arcade.lua
@@ -4693,11 +4693,8 @@ files {
 	MAME_DIR .. "src/mame/drivers/s11.cpp",
 	MAME_DIR .. "src/mame/includes/s11.h",
 	MAME_DIR .. "src/mame/drivers/s11a.cpp",
-	MAME_DIR .. "src/mame/includes/s11a.h",
 	MAME_DIR .. "src/mame/drivers/s11b.cpp",
-	MAME_DIR .. "src/mame/includes/s11b.h",
 	MAME_DIR .. "src/mame/drivers/s11c.cpp",
-	MAME_DIR .. "src/mame/includes/s11c.h",
 	MAME_DIR .. "src/mame/audio/pinsnd88.cpp",
 	MAME_DIR .. "src/mame/audio/pinsnd88.h",
 	MAME_DIR .. "src/mame/audio/s11c_bg.cpp",
diff --git a/src/mame/drivers/s11a.cpp b/src/mame/drivers/s11a.cpp
index d76670df158..27daaa3be04 100644
--- a/src/mame/drivers/s11a.cpp
+++ b/src/mame/drivers/s11a.cpp
@@ -23,7 +23,7 @@ Note: To start a game, certain switches need to be activated.  You must first pr
 *****************************************************************************************/
 
 #include "emu.h"
-#include "includes/s11a.h"
+#include "includes/s11.h"
 
 #include "cpu/m6809/m6809.h"
 #include "speaker.h"
diff --git a/src/mame/drivers/s11b.cpp b/src/mame/drivers/s11b.cpp
index d56ab229041..e8e23d23703 100644
--- a/src/mame/drivers/s11b.cpp
+++ b/src/mame/drivers/s11b.cpp
@@ -42,7 +42,7 @@
 */
 
 #include "emu.h"
-#include "includes/s11b.h"
+#include "includes/s11.h"
 
 #include "cpu/m6809/m6809.h"
 #include "speaker.h"
diff --git a/src/mame/drivers/s11c.cpp b/src/mame/drivers/s11c.cpp
index ec438e3d20f..33a9e3abfe6 100644
--- a/src/mame/drivers/s11c.cpp
+++ b/src/mame/drivers/s11c.cpp
@@ -5,7 +5,7 @@
 */
 
 #include "emu.h"
-#include "includes/s11c.h"
+#include "includes/s11.h"
 
 #include "cpu/m6809/m6809.h"
 #include "speaker.h"
diff --git a/src/mame/includes/s11.h b/src/mame/includes/s11.h
index 8bd831bcaf4..6f54d8f32e4 100644
--- a/src/mame/includes/s11.h
+++ b/src/mame/includes/s11.h
@@ -80,8 +80,8 @@ public:
 	void dig0_w(uint8_t data);
 	void dig1_w(uint8_t data);
 	void lamp0_w(uint8_t data);
-	void lamp1_w(uint8_t data) { };
-	void sol2_w(uint8_t data) { }; // solenoids 8-15
+	void lamp1_w(uint8_t data) { }
+	void sol2_w(uint8_t data) { } // solenoids 8-15
 	void sol3_w(uint8_t data); // solenoids 0-7
 	void sound_w(uint8_t data);
 
@@ -94,11 +94,11 @@ public:
 	DECLARE_WRITE_LINE_MEMBER(pias_ca2_w);
 	DECLARE_WRITE_LINE_MEMBER(pias_cb2_w);
 	DECLARE_WRITE_LINE_MEMBER(pia21_ca2_w);
-	DECLARE_WRITE_LINE_MEMBER(pia21_cb2_w) { }; // enable solenoids
-	DECLARE_WRITE_LINE_MEMBER(pia24_cb2_w) { }; // dummy to stop error log filling up
-	DECLARE_WRITE_LINE_MEMBER(pia28_ca2_w) { }; // comma3&4
-	DECLARE_WRITE_LINE_MEMBER(pia28_cb2_w) { }; // comma1&2
-	DECLARE_WRITE_LINE_MEMBER(pia30_cb2_w) { }; // dummy to stop error log filling up
+	DECLARE_WRITE_LINE_MEMBER(pia21_cb2_w) { } // enable solenoids
+	DECLARE_WRITE_LINE_MEMBER(pia24_cb2_w) { } // dummy to stop error log filling up
+	DECLARE_WRITE_LINE_MEMBER(pia28_ca2_w) { } // comma3&4
+	DECLARE_WRITE_LINE_MEMBER(pia28_cb2_w) { } // comma1&2
+	DECLARE_WRITE_LINE_MEMBER(pia30_cb2_w) { } // dummy to stop error log filling up
 	DECLARE_WRITE_LINE_MEMBER(pia_irq);
 	DECLARE_WRITE_LINE_MEMBER(main_irq);
 
@@ -163,4 +163,66 @@ private:
 	bool m_pia_irq_active;
 };
 
+
+class s11a_state : public s11_state
+{
+public:
+	s11a_state(const machine_config &mconfig, device_type type, const char *tag)
+		: s11_state(mconfig, type, tag)
+	{ }
+
+	void s11a_base(machine_config &config);
+	void s11a(machine_config &config);
+	void s11a_obg(machine_config &config);
+
+	void init_s11a();
+
+	void dig0_w(uint8_t data);
+};
+
+
+class s11b_state : public s11a_state
+{
+public:
+	s11b_state(const machine_config &mconfig, device_type type, const char *tag)
+		: s11a_state(mconfig, type, tag)
+	{ }
+
+	void s11b_base(machine_config &config);
+	void s11b(machine_config &config);
+	void s11b_jokerz(machine_config &config);
+
+	void init_s11b();
+	void init_s11b_invert();
+
+protected:
+	virtual void machine_reset() override;
+	void set_invert(bool inv) { m_invert = inv; }
+
+	void dig1_w(uint8_t data);
+	void pia2c_pa_w(uint8_t data);
+	void pia2c_pb_w(uint8_t data);
+	void pia34_pa_w(uint8_t data);
+
+private:
+	bool m_invert;  // later System 11B games start expecting inverted data to the display LED segments.
+};
+
+
+class s11c_state : public s11b_state
+{
+public:
+	s11c_state(const machine_config &mconfig, device_type type, const char *tag)
+		: s11b_state(mconfig, type, tag)
+	{ }
+
+	void s11c(machine_config &config);
+
+	void init_s11c();
+
+protected:
+	virtual void machine_reset() override;
+};
+
+
 #endif // MAME_INCLUDES_S11_H
diff --git a/src/mame/includes/s11a.h b/src/mame/includes/s11a.h
deleted file mode 100644
index 61e9878dd75..00000000000
--- a/src/mame/includes/s11a.h
+++ /dev/null
@@ -1,30 +0,0 @@
-// license:BSD-3-Clause
-// copyright-holders:Miodrag Milanovic
-/*
- * s11a.h
- *
- *  Created on: 1/01/2013
- */
-
-#ifndef MAME_INCLUDES_S11A_H
-#define MAME_INCLUDES_S11A_H
-
-#include "includes/s11.h"
-
-class s11a_state : public s11_state
-{
-public:
-	s11a_state(const machine_config &mconfig, device_type type, const char *tag)
-		: s11_state(mconfig, type, tag)
-	{ }
-
-	void s11a_base(machine_config &config);
-	void s11a(machine_config &config);
-	void s11a_obg(machine_config &config);
-
-	void init_s11a();
-
-	void dig0_w(uint8_t data);
-};
-
-#endif // MAME_INCLUDES_S11A_H
diff --git a/src/mame/includes/s11b.h b/src/mame/includes/s11b.h
deleted file mode 100644
index 4436e812525..00000000000
--- a/src/mame/includes/s11b.h
+++ /dev/null
@@ -1,41 +0,0 @@
-// license:BSD-3-Clause
-// copyright-holders:Miodrag Milanovic
-/*
- * s11b.h
- *
- *  Created on: 1/01/2013
- */
-
-#ifndef MAME_INCLUDES_S11B_H
-#define MAME_INCLUDES_S11B_H
-
-#include "includes/s11a.h"
-
-class s11b_state : public s11a_state
-{
-public:
-	s11b_state(const machine_config &mconfig, device_type type, const char *tag)
-		: s11a_state(mconfig, type, tag)
-	{ }
-
-	void s11b_base(machine_config &config);
-	void s11b(machine_config &config);
-	void s11b_jokerz(machine_config &config);
-
-	void init_s11b();
-	void init_s11b_invert();
-
-protected:
-	virtual void machine_reset() override;
-	void set_invert(bool inv) { m_invert = inv; }
-
-	void dig1_w(uint8_t data);
-	void pia2c_pa_w(uint8_t data);
-	void pia2c_pb_w(uint8_t data);
-	void pia34_pa_w(uint8_t data);
-
-private:
-	bool m_invert;  // later System 11B games start expecting inverted data to the display LED segments.
-};
-
-#endif // MAME_INCLUDES_S11B_H
diff --git a/src/mame/includes/s11c.h b/src/mame/includes/s11c.h
deleted file mode 100644
index 6d7709c0b7c..00000000000
--- a/src/mame/includes/s11c.h
+++ /dev/null
@@ -1,30 +0,0 @@
-// license:BSD-3-Clause
-// copyright-holders:Miodrag Milanovic
-/*
- * s11c.h
- *
- *  Created on: 1/01/2013
- */
-
-#ifndef MAME_INCLUDES_S11C_H
-#define MAME_INCLUDES_S11C_H
-
-#include "includes/s11b.h"
-
-class s11c_state : public s11b_state
-{
-public:
-	s11c_state(const machine_config &mconfig, device_type type, const char *tag)
-		: s11b_state(mconfig, type, tag)
-	{ }
-
-	void s11c(machine_config &config);
-
-	void init_s11c();
-
-protected:
-	virtual void machine_reset() override;
-};
-
-
-#endif // MAME_INCLUDES_S11C_H