diff --git a/src/devices/video/topcat.cpp b/src/devices/video/topcat.cpp
index 7565dd57791..db162733fcd 100644
--- a/src/devices/video/topcat.cpp
+++ b/src/devices/video/topcat.cpp
@@ -11,8 +11,8 @@ DEFINE_DEVICE_TYPE(TOPCAT, topcat_device, "topcat", "HP Topcat ASIC")
 
 topcat_device::topcat_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock) :
 	device_t(mconfig, type, tag, owner, clock),
-	m_cursor_timer(nullptr),
 	m_int_write_func(*this),
+	m_cursor_timer(nullptr),
 	m_vram(*this, "^vram")
 {
 }
diff --git a/src/devices/video/topcat.h b/src/devices/video/topcat.h
index 367311cd0a6..1f73c90729e 100644
--- a/src/devices/video/topcat.h
+++ b/src/devices/video/topcat.h
@@ -41,7 +41,6 @@ public:
 
 	bool plane_enabled();
 
-	devcb_write_line m_int_write_func;
 protected:
 	topcat_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock);
 
@@ -123,6 +122,9 @@ private:
 	}
 
 	void update_int();
+
+	devcb_write_line m_int_write_func;
+
 	uint16_t m_vblank;
 	uint8_t m_wmove_active;
 	uint16_t m_vert_retrace_intrq;