sinclair/sprinter.cpp: Added access to internal z84 IO through the BUS (#14189)

Author: holub

src/mame/sinclair/sprinter.cpp

@@ -1429,6 +1429,19 @@ void sprinter_state::init_taps()
 			check_accel(false, offset, data);
 		}
 	});
+
+	m_maincpu->space(AS_IO).install_write_tap(0x0000, 0xffff, "cpu_io_w", [this](offs_t offset, u8 &data, u8 mem_mask)
+	{
+		// Internal z84 ports are not accesable through IO map, hence they need special case here
+		static const std::unordered_set<u8> z84_int = {
+			0x10, 0x11, 0x12, 0x13,
+			0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+			0xee, 0xef,
+			0xf0, 0xf1, 0xf4
+		};
+		if (z84_int.find(u8(offset)) != z84_int.end())
+			dcp_w(offset, data);
+	});
 }
 
 void sprinter_state::machine_start()