Check for floating bus

Fixes CosmosOS#1056: Does not boot if there is no IDE Secondary Master (VirtualBox)
nealhoang · Oct 11, 2018 · 87a233a · 87a233a
1 parent 2ca4b2a
commit 87a233a
Showing 1 changed file with 8 additions and 0 deletions.
diff --git a/source/Cosmos.HAL2/BlockDevice/AtaPio.cs b/source/Cosmos.HAL2/BlockDevice/AtaPio.cs
@@ -163,6 +163,14 @@ public AtaPio(Core.IOGroup.ATA aIO, Ata.ControllerIdEnum aControllerId, Ata.BusP
 		public SpecLevel DiscoverDrive()
 		{
 			SelectDrive(0);
+
+			// Read status before sending command. If 0xFF, it's a floating
+			// bus (nothing connected)
+			if (IO.Status.Byte == 0xFF)
+			{
+				return SpecLevel.Null;
+			}
+
 			var xIdentifyStatus = SendCmd(Cmd.Identify, false);
 			// No drive found, go to next
 			if (xIdentifyStatus == Status.None)