diff --git a/Machines/Acorn/Archimedes/FloppyDisc.hpp b/Machines/Acorn/Archimedes/FloppyDisc.hpp
index f203f84d6..a60097f2c 100644
--- a/Machines/Acorn/Archimedes/FloppyDisc.hpp
+++ b/Machines/Acorn/Archimedes/FloppyDisc.hpp
@@ -16,7 +16,7 @@ template <typename InterruptObserverT>
 class FloppyDisc: public WD::WD1770, public WD::WD1770::Delegate {
 public:
 	FloppyDisc(InterruptObserverT &observer) : WD::WD1770(P1772), observer_(observer) {
-		emplace_drives(1, 8000000, 300, 2, Storage::Disk::Drive::ReadyType::IBMRDY);	// A guess at RDY type.
+		emplace_drives(1, 8000000, 300, 2, Storage::Disk::Drive::ReadyType::ShugartModifiedRDY);	// A guess at RDY type.
 		set_delegate(this);
 	}
 
diff --git a/Machines/Acorn/Archimedes/InputOutputController.hpp b/Machines/Acorn/Archimedes/InputOutputController.hpp
index ebaa1f1bc..6311a6fcc 100644
--- a/Machines/Acorn/Archimedes/InputOutputController.hpp
+++ b/Machines/Acorn/Archimedes/InputOutputController.hpp
@@ -202,7 +202,7 @@ struct InputOutputController: public ClockingHint::Observer {
 						uint8_t value = control_ | 0xc0;
 						value &= ~(i2c_.data() ? 0x01 : 0x00);
 						value &= ~(i2c_.clock() ? 0x02 : 0x00);
-						value &= ~(floppy_.ready() ? 0x04 : 0x00);
+						value &= ~(floppy_.ready() ? 0x00 : 0x04);
 						value &= ~(video_.flyback_active() ? 0x00 : 0x80);	// i.e. high during flyback.
 						set_byte(value);
 //						logger.error().append("IOC control read: C:%d D:%d", !(value & 2), !(value & 1));
diff --git a/Storage/Disk/Controller/DiskController.hpp b/Storage/Disk/Controller/DiskController.hpp
index ae7fbe163..a1a1a4a39 100644
--- a/Storage/Disk/Controller/DiskController.hpp
+++ b/Storage/Disk/Controller/DiskController.hpp
@@ -122,6 +122,9 @@ class Controller:
 		Drive &get_drive(size_t index) {
 			return *drives_[index];
 		}
+		const Drive &get_drive(size_t index) const {
+			return *drives_[index];
+		}
 
 		void for_all_drives(const std::function<void(Drive &, size_t)> &func) {
 			size_t index = 0;