diff --git a/src/mame/drivers/osi.cpp b/src/mame/drivers/osi.cpp
index 96f82f51165..9334a256333 100644
--- a/src/mame/drivers/osi.cpp
+++ b/src/mame/drivers/osi.cpp
@@ -827,6 +827,7 @@ void c1p_state::c1p(machine_config &config)
 	m_discrete->set_intf(osi600c_discrete_interface);
 	m_discrete->add_route(ALL_OUTPUTS, "mono", 0.50);
 	BEEP(config, "beeper", 300).add_route(ALL_OUTPUTS, "mono", 0.50);
+	TIMER(config, m_beep_timer).configure_generic(FUNC(c1p_state::beep_timer));
 
 	PIA6821(config, "pia_1", 0);
 	PIA6821(config, "pia_2", 0);
@@ -922,22 +923,15 @@ ROM_END
 
 /* Driver Initialization */
 
-void c1p_state::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
+TIMER_DEVICE_CALLBACK_MEMBER(c1p_state::beep_timer)
 {
-	switch (id)
-	{
-	case TIMER_SETUP_BEEP:
-		m_beeper->set_state(0);
-		m_beeper->set_clock(300);
-		break;
-	default:
-		throw emu_fatalerror("Unknown id in c1p_state::device_timer");
-	}
+	m_beeper->set_state(0);
+	m_beeper->set_clock(300);
 }
 
 void c1p_state::init_c1p()
 {
-	timer_set(attotime::zero, TIMER_SETUP_BEEP);
+	m_beep_timer->adjust(attotime::zero);
 }
 
 
diff --git a/src/mame/includes/osi.h b/src/mame/includes/osi.h
index 379eb16001b..3d459cdc7f9 100644
--- a/src/mame/includes/osi.h
+++ b/src/mame/includes/osi.h
@@ -101,25 +101,21 @@ public:
 	c1p_state(const machine_config &mconfig, device_type type, const char *tag)
 		: sb2m600_state(mconfig, type, tag)
 		, m_beeper(*this, "beeper")
+		, m_beep_timer(*this, "beep_timer")
 	{ }
 
 	void init_c1p();
 	void c1p(machine_config &config);
 
 protected:
-	enum
-	{
-		TIMER_SETUP_BEEP
-	};
-
 	virtual void machine_start() override;
-	virtual void device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) override;
-
 	void osi630_ctrl_w(uint8_t data);
 	void osi630_sound_w(uint8_t data);
 	void c1p_mem(address_map &map);
+	TIMER_DEVICE_CALLBACK_MEMBER(beep_timer);
 
 	required_device<beep_device> m_beeper;
+	required_device<timer_device> m_beep_timer;
 };
 
 class c1pmf_state : public c1p_state