diff --git a/src/emu/machine/mos6526.c b/src/emu/machine/mos6526.c
index a44336fb23b..94f1c667bfa 100644
--- a/src/emu/machine/mos6526.c
+++ b/src/emu/machine/mos6526.c
@@ -588,6 +588,7 @@ mos6526_device::mos6526_device(const machine_config &mconfig, device_type type,
 		device_execute_interface(mconfig, *this),
 		m_icount(0),
 		m_variant(variant),
+		m_tod_clock(0),
 		m_write_irq(*this),
 		m_write_pc(*this),
 		m_write_cnt(*this),