diff --git a/src/mame/drivers/ksys573.c b/src/mame/drivers/ksys573.c
index 5ea5a41a18c..7b24779f9b8 100644
--- a/src/mame/drivers/ksys573.c
+++ b/src/mame/drivers/ksys573.c
@@ -756,14 +756,19 @@ TIMER_CALLBACK_MEMBER(ksys573_state::atapi_xfer_end)
 
 	address_space &space = m_maincpu->space(AS_PROGRAM);
 
-	while( m_atapi_xfersize > 0 )
+	for (int i = 0; i < m_atapi_xfersize; i++)
 	{
 		UINT32 d = m_ata->read_cs0(space, (UINT32) 0, (UINT32) 0xffff) << 0;
 		d |= m_ata->read_cs0(space, (UINT32) 0, (UINT32) 0xffff) << 16;
 
 		m_p_n_psxram[ m_atapi_xferbase / 4 ] = d;
 		m_atapi_xferbase += 4;
-		m_atapi_xfersize--;
+	}
+
+	/// HACK: konami80s only works if you dma more data than requested
+	if ((m_ata->read_cs1(space, (UINT32) 6, (UINT32) 0xffff) & 8) != 0)
+	{
+		m_atapi_timer->adjust(m_maincpu->cycles_to_attotime((ATAPI_CYCLES_PER_SECTOR * (m_atapi_xfersize/512))));
 	}
 }