diff --git a/src/mame/drivers/ti74.cpp b/src/mame/drivers/ti74.cpp
index dce46d5969c..ed51e4dffce 100644
--- a/src/mame/drivers/ti74.cpp
+++ b/src/mame/drivers/ti74.cpp
@@ -378,10 +378,10 @@ static INPUT_PORTS_START( ti74 )
 	PORT_BIT( 0x80, IP_ACTIVE_HIGH, IPT_UNUSED )
 
 	PORT_START("IN.7")
-	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_PLUS_PAD) PORT_CHAR(UCHAR_MAMEKEY(PLUS_PAD)) PORT_NAME("+     s(y)")
+	PORT_BIT( 0x01, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_PLUS_PAD) PORT_CHAR('+') PORT_NAME("+     s(y)")
 	PORT_BIT( 0x02, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_MINUS_PAD) PORT_CODE(KEYCODE_MINUS) PORT_CHAR('-') PORT_NAME("-     s(x)")
-	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_ASTERISK) PORT_CHAR(UCHAR_MAMEKEY(ASTERISK)) PORT_NAME("*     y" UTF8_NONSPACE_MACRON)
-	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_SLASH_PAD) PORT_CODE(KEYCODE_SLASH) PORT_CHAR(UCHAR_MAMEKEY(SLASH_PAD)) PORT_NAME("/     x" UTF8_NONSPACE_MACRON)
+	PORT_BIT( 0x04, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_ASTERISK) PORT_CHAR('*') PORT_NAME("*     y" UTF8_NONSPACE_MACRON)
+	PORT_BIT( 0x08, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_SLASH_PAD) PORT_CODE(KEYCODE_SLASH) PORT_CHAR('/') PORT_NAME("/     x" UTF8_NONSPACE_MACRON)
 	PORT_BIT( 0x10, IP_ACTIVE_HIGH, IPT_UNUSED )
 	PORT_BIT( 0x20, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_LALT) PORT_CODE(KEYCODE_RALT) PORT_CHAR(UCHAR_MAMEKEY(F1)) PORT_NAME("FN     hyp")
 	PORT_BIT( 0x40, IP_ACTIVE_HIGH, IPT_KEYBOARD ) PORT_CODE(KEYCODE_LCONTROL) PORT_CODE(KEYCODE_RCONTROL) PORT_CHAR(UCHAR_SHIFT_2) PORT_NAME("CTL     STAT")