diff --git a/Machines/Apple/AppleII/AppleII.cpp b/Machines/Apple/AppleII/AppleII.cpp
index 8e04458d5..8a857c6ef 100644
--- a/Machines/Apple/AppleII/AppleII.cpp
+++ b/Machines/Apple/AppleII/AppleII.cpp
@@ -372,6 +372,14 @@ template <Analyser::Static::AppleII::Target::Model model> class ConcreteMachine:
 			}
 			const auto roms = rom_fetcher(rom_descriptions);
 
+			// Try to install a Disk II card now, before checking the ROM list,
+			// to make sure that Disk II dependencies have been communicated.
+			if(target.disk_controller != Target::DiskController::None) {
+				// Apple recommended slot 6 for the (first) Disk II.
+				install_card(6, new Apple::II::DiskIICard(rom_fetcher, target.disk_controller == Target::DiskController::SixteenSector));
+			}
+
+			// Now, check and move the ROMs.
 			if(!roms[0] || !roms[1]) {
 				throw ROMMachine::Error::MissingROMs;
 			}
@@ -383,11 +391,6 @@ template <Analyser::Static::AppleII::Target::Model model> class ConcreteMachine:
 
 			video_.set_character_rom(*roms[0]);
 
-			if(target.disk_controller != Target::DiskController::None) {
-				// Apple recommended slot 6 for the (first) Disk II.
-				install_card(6, new Apple::II::DiskIICard(rom_fetcher, target.disk_controller == Target::DiskController::SixteenSector));
-			}
-
 			// Set up the default memory blocks. On a II or II+ these values will never change.
 			// On a IIe they'll be affected by selection of auxiliary RAM.
 			set_main_paging();
diff --git a/Machines/Apple/AppleII/DiskIICard.cpp b/Machines/Apple/AppleII/DiskIICard.cpp
index dae7b30cf..11349e1fc 100644
--- a/Machines/Apple/AppleII/DiskIICard.cpp
+++ b/Machines/Apple/AppleII/DiskIICard.cpp
@@ -15,7 +15,7 @@ DiskIICard::DiskIICard(const ROMMachine::ROMFetcher &rom_fetcher, bool is_16_sec
 	if(is_16_sector) {
 		roms = rom_fetcher({
 			{"DiskII", "the Disk II 16-sector boot ROM", "boot-16.rom", 256, 0xce7144f6},
-			{"DiskII", "the Disk II 16-sector state machine ROM", "state-machine-16.rom", 256, { 0xce7144f6, 0xb72a2c70 } }
+			{"DiskII", "the Disk II 16-sector state machine ROM", "state-machine-16.rom", 256, { 0x9796a238, 0xb72a2c70 } }
 		});
 	} else {
 		roms = rom_fetcher({
@@ -23,6 +23,10 @@ DiskIICard::DiskIICard(const ROMMachine::ROMFetcher &rom_fetcher, bool is_16_sec
 			{"DiskII", "the Disk II 13-sector state machine ROM", "state-machine-13.rom", 256, 0x62e22620 }
 		});
 	}
+	if(!roms[0] || !roms[1]) {
+		throw ROMMachine::Error::MissingROMs;
+	}
+
 	boot_ = std::move(*roms[0]);
 	diskii_.set_state_machine(*roms[1]);
 	set_select_constraints(None);
diff --git a/Machines/Oric/Oric.cpp b/Machines/Oric/Oric.cpp
index bbeea6290..b90ce9fd8 100644
--- a/Machines/Oric/Oric.cpp
+++ b/Machines/Oric/Oric.cpp
@@ -241,6 +241,7 @@ template <Analyser::Static::Oric::Target::DiskInterface disk_interface> class Co
 					rom_names.emplace_back(machine_name, "Pravetz BASIC", "pravetz.rom", 16*1024, 0x58079502);
 				break;
 			}
+			size_t diskii_state_machine_index = 0;
 			switch(disk_interface) {
 				default: break;
 				case Analyser::Static::Oric::Target::DiskInterface::Microdisc:
@@ -248,6 +249,9 @@ template <Analyser::Static::Oric::Target::DiskInterface disk_interface> class Co
 				break;
 				case Analyser::Static::Oric::Target::DiskInterface::Pravetz:
 					rom_names.emplace_back(machine_name, "the 8DOS boot ROM", "8dos.rom", 512, 0x49a74c06);
+					// These ROM details are coupled with those in the DiskIICard.
+					diskii_state_machine_index = rom_names.size();
+					rom_names.push_back({"DiskII", "the Disk II 16-sector state machine ROM", "state-machine-16.rom", 256, { 0x9796a238, 0xb72a2c70 }});
 				break;
 			}
 
@@ -272,12 +276,7 @@ template <Analyser::Static::Oric::Target::DiskInterface disk_interface> class Co
 					pravetz_rom_ = std::move(*roms[2]);
 					pravetz_rom_.resize(512);
 
-					// This ROM name is coupled with that in the DiskIICard.
-					const auto state_machine_rom = rom_fetcher({ {"DiskII", "the Disk II 16-sector state machine ROM", "state-machine-16.rom", 256, { 0xce7144f6, 0xb72a2c70 } } });
-					if(!state_machine_rom[0]) {
-						throw ROMMachine::Error::MissingROMs;
-					}
-					diskii_.set_state_machine(*state_machine_rom[0]);
+					diskii_.set_state_machine(*roms[diskii_state_machine_index]);
 				} break;
 			}