UARTReplacement now always returns 1 for port 0x133b bit 4 (1 if the …

…Tx buffer is empty).
Threetwosevensixseven · Dec 16, 2024 · 7cab4c1 · 7cab4c1
1 parent 713b016
commit 7cab4c1
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Showing 2 changed files with 9 additions and 3 deletions.
diff --git a/UARTReplacement/Properties/AssemblyInfoExtra.cs b/UARTReplacement/Properties/AssemblyInfoExtra.cs
@@ -4,7 +4,7 @@
 
 using System.Reflection;
 
-[assembly: AssemblyConfiguration("7e20a6b")]
+[assembly: AssemblyConfiguration("713b016")]
 [assembly: AssemblyCopyright("Copyright © 2019-2024 Robin Verhagen-Guest")]
 [assembly: AssemblyVersion("1.6.0.0")]
 [assembly: AssemblyFileVersion("1.6.0.0")]
diff --git a/UARTReplacement/UARTReplacement_Device.cs b/UARTReplacement/UARTReplacement_Device.cs
@@ -223,10 +223,16 @@ public byte Read(eAccess _type, int _port, int _id, out bool _isvalid)
                         // Reads from this port return a status flag in bit 0 indicating whether 
                         // there is any data available to read from the UART buffer.
                         _isvalid = true;
+                        // bit 4 = 1 if the Tx buffer is empty. Hardcode this to 1 for now, as the PC OS has a very large TX buffer.
+                        //   It will work better for program that wait for this flag to be 1 before continuing.
+                        // bit 0 = 1 if the Rx buffer contains bytes. This is reporting our internal RX buffer, which is drained as
+                        //   fast as possble from the serial buffer, and kept in currentBuffer for port 0x143b reads to return it.
+                        //   In future, consider also including the serial port .BytesToRead count.
+                        // Other flags can also be implemented in future.
                         if (currentBuffer.Count > 0)
-                            return 1;
+                            return 0b_0001_0001;
                         else
-                            return 0;
+                            return 0b_0001_0000;
                 }
             }
             catch (Exception ex)