Acy\VT100 Emulation


Acnin5\To properly emulate a VT100 it is necessary to send the proper command sequences.  The following information is taken from the Digital VT240 manual.

In line-editing mode (monitor mode), the cursor controls are:
Cursor up     CSI A
Cursor down   CSI B
Cursor right  CSI C
Cursor left   CSI D


In application mode (editors), the cursor controls and keypad controls are:
Cursor up     SS3 A
Cursor down   SS3 B
Cursor right  SS3 C
Cursor left   SS3 D

PF1           SS3 P
PF2           SS3 Q
PF3           SS3 R
PF4           SS3 S

Keypad 0      SS3 p
Keypad 1      SS3 q
Keypad 2      SS3 r
Keypad 3      SS3 s
Keypad 4      SS3 t
Keypad 5      SS3 u
Keypad 6      SS3 v
Keypad 7      SS3 w
Keypad 8      SS3 x
Keypad 9      SS3 y
Keypad -      SS3 m
Keypad ,      SS3 l
Keypad .      SS3 n
Keypad ENTER  SS3 M

Where CSI is decimal 155 and SS3 is decimal 143 in ACSII 8-bit code.  Alternatively, the seven-bit escape sequences ESC [ and ESC O may be used, respectively.  In VAX/VMS the escape sequences are recognized without the second character.  The Commodore left arrow sends the decimal code 27 coresponding to the ASCII ESC.  I have not been able to find the equivalences for CSI (decimal 155) and SS3 (143).

I have tested the escape sequences with KERMIT2A which still has VT52 emulation as far as the keyboard and it works both in line-editing mode and in application mode (for the screen editor EVE).  I attempted to use ITT but it is inconsistent with my current system since I have a dial phone and 1670 modem and ITT does not pass the necessary Hayes characters.  However, one should be able to redefine the tables used by ITT or other similar programs to send the appropriate control or escape sequences.

Also, VAX/VMS is very forgiving on the escape sequences and one does not have to send the second character (i.e. [ or O).