diff --git a/src/mess/machine/c2040.c b/src/mess/machine/c2040.c
index c8dfe218b3a..406488a21fe 100644
--- a/src/mess/machine/c2040.c
+++ b/src/mess/machine/c2040.c
@@ -1477,6 +1477,7 @@ c2040_device::c2040_device(const machine_config &mconfig, device_type type, cons
 		m_atna(1),
 		m_ds(-1),
 		m_bit_count(0),
+		m_sr(0),
 		m_pi(0),
 		m_ready(0),
 		m_mode(0),
@@ -1513,6 +1514,7 @@ c2040_device::c2040_device(const machine_config &mconfig, const char *tag, devic
 		m_atna(1),
 		m_ds(-1),
 		m_bit_count(0),
+		m_sr(0),
 		m_pi(0),
 		m_ready(0),
 		m_mode(0),