diff --git a/tests/mfpi.mac b/tests/mfpi.mac
new file mode 100644
index 0000000..2dfadcf
--- /dev/null
+++ b/tests/mfpi.mac
@@ -0,0 +1,65 @@
+; make sure current run-mode is kernel and previous is user
+	MOV	#0177776,R0
+	MOV	#030000,(R0)
+	NOP
+
+; initialize kernel- and user stackpointers
+; kernel
+	MOV	#1000,R6
+;; user
+;	MOV	#0177717,R0
+;	MOV	#1000,(R0)
+
+; user: 060000-080000 will be mapped to physical address 020000
+	MOV	#0177646,R0
+; 020000 / 0100 (0100 => 64 decimal)
+	MOV	#0200,(R0)
+	NOP
+
+; user: make sure write- and read-access is possible
+	MOV	#0177606,R0
+	MOV	#077406,(R0)
+
+; kernel: flat mapping
+; 0-010000 -> 0
+	MOV	#0172340,R0
+	MOV	#0000,(R0)
+; 060000-0100000 -> 060000
+	MOV	#0172346,R0
+	MOV	#0600,(R0)
+	NOP
+
+; kernel: make sure write- and read-access is possible
+; 0-010000
+	MOV	#0172300,R0
+	MOV	#077406,(R0)
+; 060000-0100000
+	MOV	#0172306,R0
+	MOV	#077406,(R0)
+
+; place a value at 020000 kernelspace which is
+; 060000 in userspace
+	MOV	#020000,R0
+	MOV	#01234,(R0)
+
+; MRR0
+	MOV	#0177572,R0
+; enable MMU traps
+	BIS	#512,(R0)
+; enable MMU
+	BIS	#1,(R0)
+
+; get word from 060000 in userspace and put that on
+; the kernel stack
+	MOV	#060000,R0
+	MFPI	(R0)
+	NOP
+
+; check for 01234
+	MOV	(SP)+,R0
+	CMP	#01234,R0
+	NOP
+
+	HALT
+
+	make_raw
diff --git a/tty.h b/tty.h
index 20d3d6f..abe6090 100644
--- a/tty.h
+++ b/tty.h
@@ -25,7 +25,6 @@ private:
 	bool     have_char_1  { false };  // RCVR BUSY bit high (11)
 	bool     have_char_2  { false };  // RCVR DONE bit high (7)
 	uint16_t registers[4] { 0 };
-	bool     withUI       { false };
 
 public:
 	tty(console *const c);