diff --git a/src/mess/includes/c128.h b/src/mess/includes/c128.h
index 6d12f52d038..2c9351f462b 100644
--- a/src/mess/includes/c128.h
+++ b/src/mess/includes/c128.h
@@ -179,35 +179,9 @@ public:
 
 /*----------- defined in machine/c128.c -----------*/
 
-WRITE8_HANDLER(c128_mmu8722_port_w);
-READ8_HANDLER(c128_mmu8722_port_r);
-WRITE8_HANDLER(c128_mmu8722_ff00_w);
-READ8_HANDLER(c128_mmu8722_ff00_r);
-WRITE8_HANDLER(c128_write_0000);
-WRITE8_HANDLER(c128_write_1000);
-WRITE8_HANDLER(c128_write_4000);
-WRITE8_HANDLER(c128_write_8000);
-WRITE8_HANDLER(c128_write_a000);
-WRITE8_HANDLER(c128_write_c000);
-WRITE8_HANDLER(c128_write_d000);
-WRITE8_HANDLER(c128_write_e000);
-WRITE8_HANDLER(c128_write_ff00);
-WRITE8_HANDLER(c128_write_ff05);
-
-
-extern MACHINE_START( c128 );
-extern MACHINE_RESET( c128 );
 extern INTERRUPT_GEN( c128_frame_interrupt );
 
-void c128_bankswitch_64(running_machine &machine, int reset);
-
-extern READ8_DEVICE_HANDLER(c128_m6510_port_read);
-extern WRITE8_DEVICE_HANDLER(c128_m6510_port_write);
-
 extern const mos6526_interface c128_ntsc_cia0, c128_pal_cia0;
 extern const mos6526_interface c128_ntsc_cia1, c128_pal_cia1;
 
-WRITE_LINE_DEVICE_HANDLER( c128_iec_srq_w );
-WRITE_LINE_DEVICE_HANDLER( c128_iec_data_w );
-
 #endif /* __C128_H__ */
diff --git a/src/mess/machine/c128.c b/src/mess/machine/c128.c
index dcc8fd7328f..0bb4eee5e75 100644
--- a/src/mess/machine/c128.c
+++ b/src/mess/machine/c128.c
@@ -251,19 +251,12 @@ const mos6526_interface c128_pal_cia0 =
 
 WRITE_LINE_MEMBER( c128_state::iec_srq_w )
 {
-	if (!MMU_FSDIR)
-	{
-		mos6526_flag_w(m_cia1, state);
-		mos6526_cnt_w(m_cia1, state);
-	}
+	mos6526_cnt_w(m_cia1, MMU_FSDIR || state);
 }
 
 WRITE_LINE_MEMBER( c128_state::iec_data_w )
 {
-	if (!MMU_FSDIR)
-	{
-		mos6526_sp_w(m_cia1, state);
-	}
+	mos6526_sp_w(m_cia1, MMU_FSDIR || state);
 }
 
 /*
@@ -830,6 +823,8 @@ WRITE8_MEMBER( c128_state::mmu8722_port_w )
 		bankswitch(0);
 		iec_srq_out_w();
 		iec_data_out_w();
+		mos6526_cnt_w(m_cia1, MMU_FSDIR || m_iec->srq_r());
+		mos6526_sp_w(m_cia1, MMU_FSDIR || m_iec->data_r());
 		break;
 	case 0:
 	case 6:
diff --git a/src/mess/machine/c1571.c b/src/mess/machine/c1571.c
index 6773991fe8c..bf2b1addd55 100644
--- a/src/mess/machine/c1571.c
+++ b/src/mess/machine/c1571.c
@@ -252,11 +252,8 @@ WRITE8_MEMBER( base_c1571_device::via0_pa_w )
 		set_iec_data();
 		set_iec_srq();
 
-		if (!m_ser_dir)
-		{
-			//m_cia->cnt_w(m_bus->srq_r());
-			//m_cia->sp_w(m_bus->data_r());
-		}
+		m_cia->cnt_w(m_ser_dir || m_bus->srq_r());
+		m_cia->sp_w(m_ser_dir || m_bus->data_r());
 	}
 
 	// side select
@@ -802,10 +799,7 @@ void base_c1571_device::device_reset()
 
 void base_c1571_device::cbm_iec_srq(int state)
 {
-	if (!m_ser_dir)
-	{
-		m_cia->cnt_w(state);
-	}
+	m_cia->cnt_w(m_ser_dir || state);
 }
 
 
@@ -828,10 +822,7 @@ void base_c1571_device::cbm_iec_atn(int state)
 
 void base_c1571_device::cbm_iec_data(int state)
 {
-	if (!m_ser_dir)
-	{
-		m_cia->sp_w(state);
-	}
+	m_cia->sp_w(m_ser_dir || state);
 }
 
 
diff --git a/src/mess/machine/c1581.c b/src/mess/machine/c1581.c
index f1c649538db..6f633a1f0b4 100644
--- a/src/mess/machine/c1581.c
+++ b/src/mess/machine/c1581.c
@@ -260,10 +260,18 @@ WRITE8_MEMBER( base_c1581_device::cia_pb_w )
 	m_atn_ack = BIT(data, 4);
 
 	// fast serial direction
-	m_fast_ser_dir = BIT(data, 5);
+	int fast_ser_dir = BIT(data, 5);
 
-	set_iec_data();
-	set_iec_srq();
+	if (m_fast_ser_dir != fast_ser_dir)
+	{
+		m_fast_ser_dir = fast_ser_dir;
+
+		set_iec_data();
+		set_iec_srq();
+
+		m_cia->cnt_w(m_fast_ser_dir || m_bus->srq_r());
+		m_cia->sp_w(m_fast_ser_dir || m_bus->data_r());
+	}
 }
 
 static MOS8520_INTERFACE( cia_intf )
@@ -458,10 +466,7 @@ void base_c1581_device::device_reset()
 
 void base_c1581_device::cbm_iec_srq(int state)
 {
-	if (!m_fast_ser_dir)
-	{
-		m_cia->cnt_w(state);
-	}
+	m_cia->cnt_w(m_fast_ser_dir || state);
 }
 
 
@@ -483,10 +488,7 @@ void base_c1581_device::cbm_iec_atn(int state)
 
 void base_c1581_device::cbm_iec_data(int state)
 {
-	if (!m_fast_ser_dir)
-	{
-		m_cia->sp_w(state);
-	}
+	m_cia->sp_w(m_fast_ser_dir || state);
 }