--- nono/vm/sio.h	2026/04/29 17:04:50	1.1.1.6
+++ nono/vm/sio.h	2026/04/29 17:05:07	1.1.1.8
@@ -9,8 +9,7 @@
 #include "device.h"
 #include "upd7201.h"
 
-class SIODevice
-	: public uPD7201Device
+class SIODevice : public uPD7201Device
 {
 	using inherited = uPD7201Device;
  public:
@@ -27,6 +26,8 @@ class SIODevice
 	static const uint32 NPORT = 4;
 	uint64 Peek(uint32 offset);
 
+	void Tx(int ch, uint32 data) override;
+
  private:
 	void Interrupt() override;
 };