diff --git a/src/devices/bus/isa/aha1542.h b/src/devices/bus/isa/aha1542.h
index 96a02757999..e2d51d8f048 100644
--- a/src/devices/bus/isa/aha1542.h
+++ b/src/devices/bus/isa/aha1542.h
@@ -28,6 +28,7 @@ class aha1542_device : public device_t,
 						public device_isa16_card_interface
 {
 public:
+	static constexpr feature_type unemulated_features() { return feature::DISK; }
 	// construction/destruction
 	aha1542_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);
 
diff --git a/src/devices/bus/isa/cga.h b/src/devices/bus/isa/cga.h
index 5dd14acd103..d482859fbb4 100644
--- a/src/devices/bus/isa/cga.h
+++ b/src/devices/bus/isa/cga.h
@@ -26,6 +26,7 @@ class isa8_cga_device :
 	friend class isa8_cga_pc1512_device;
 
 public:
+	static constexpr feature_type imperfect_features() { return feature::GRAPHICS; }
 	// construction/destruction
 	isa8_cga_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock);