character	VT-52				M100 w DVI
--------------------------------------------------------------------------
NUL (^@)	ignored				ignored
BEL (^G)	bell				bell
BS  (^H)	backspace			backspace
		UNLESS AT START OF LINE
TAB (^I)	moves to next tab stop		moves to next tab stop
		UNLESS AT END OF LINE
LF  (^J)	cursor down one	line 		cursor down one line
CR  (^M)	Cursor to start of current	Cursor to start of current
		line				line
ESC (^[)	start of escape sequence	start of escape sequence
DEL		ignored				destructive backspace

ESCape sequence	VT-52				M100 w DVI
--------------------------------------------------------------------------
ESC =		enter alternate keypad mode	ignored
ESC >		exit  alternate keypad mode	ignored
ESC A		cursor up			cursor up
ESC B		cursor down			cursor down
ESC C		cursor right			cursor right
ESC D		cursor left			cursor left
ESC F		enter graphics mode		ignored
ESC G		exit graphics mode		ignored
ESC H		cursor home			cursor home
ESC I		reverse lf			reverse lf
ESC J		erase to end of screen		erase to end of screen
ESC K		erase to end of line		erase to end of line
ESC Y		direct cursor addressing	direct cursor addressing
ESC Z		send terminal id string		ignored
		(ESC /K for VT52 without
		hard copy unit,
		ESC /L for VT-52 with
		hard copy unit)
ESC [		enter hold screen mode		ignored
ESC \		exit  hold screen mode		ignored

VT52 keypad codes
key			numeric mode		alternate mode
--------------------------------------------------------------------------
0			0			ESC ?p
1			1			ESC ?q
2			2			ESC ?r
3			3			ESC ?s
4			4			ESC ?t
5			5			ESC ?u
6			6			ESC ?v
7			7			ESC ?w
8			8			ESC ?x
9			9			ESC ?y
.			.			ESC ?n
ENTER			CR			ESC ?M
up arrow		ESC A			ESC A
down arrow		ESC B			ESC B
right arrow		ESC C			ESC C
left arrow		ESC D			ESC D
left blank key		ESC P			ESC P
center blank key	ESC Q			ESC Q
right blank key		ESC R			ESC R

VT-52 graphics
ASCII	normal	graphics		M100 graphics
--------------------------------------------------------------------------
 94	^	blank
 95	_	blank
 96	`	reserved		?
 97	a	solid rectangle		239
 98	b	1/			n/a
 99	c	3/			n/a
100	d	5/			n/a
101	e	7/			n/a
102	f	degrees			166
103	g	plus or minus		141
104	h	right arrow		154
105	i	ellipsis		?
106	j	divide by		n/a
107	k	down arrow		153
108	l	bar at scan 0		n/a
109	m	bar at scan 1		n/a
110	n	bar at scan 2		n/a
111	o	bar at scan 3		241
112	p	bar at scan 4		n/a
113	q	bar at scan 5		n/a
114	r	bar at scan 6		n/a
115	s	bar at scan 7		_ (95)
116	t	subscript 0		n/a
117	u	subscript 1		n/a
118	v	subscript 2		n/a
119	w	subscript 3		n/a
120	x	subscript 4		n/a
121	y	subscript 5		n/a
122	z	subscript 6		n/a
123	{	subscript 7		n/a
124	|	subscript 8		n/a
125	}	subscript 9		n/a
126	~	paragraph		175