The X16 has a built-in screen editor that is backwards-compatible with the C64, but has many new features.
The editor's default mode is 80x60 text mode. The following text mode resolutions are supported:
Mode | Description |
---|---|
$00 | 80x60 text |
$01 | 80x30 text |
$02 | 40x60 text |
$03 | 40x30 text |
$04 | 40x15 text |
$05 | 20x30 text |
$06 | 20x15 text |
$80 | 320x200@256c 40x25 text |
Mode $80 contains two layers: a text layer on top of a graphics screen. In this mode, text color 0 is translucent instead of black.
To switch modes, use the BASIC statement SCREEN
or the
KERNAL API screen_mode
. In BASIC, the F4 key toggles
between modes 0 (80x60) and 3 (40x30).
In addition to PETSCII, the X16 also supports the ISO-8859-15 character encoding. In ISO-8859-15 mode ("ISO mode"):
CHR$()
in BASIC and BSOUT
in
machine language) now complies with ASCII and ISO-8859-15.This is the encoding:
0123456789ABCDEF
0x| |
1x| |
2x| !"#$%&'()*+,-./|
3x|0123456789:;<=>?|
4x|@ABCDEFGHIJKLMNO|
5x|PQRSTUVWXYZ[\]^_|
6x|`abcdefghijklmno|
7x|pqrstuvwxyz{|}~ |
8x| |
9x| |
Ax| ¡¢£€¥Š§š©ª«¬ ®¯|
Bx|°±²³Žµ¶·ž¹º»ŒœŸ¿|
Cx|ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏ|
Dx|ÐÑÒÓÔÕÖרÙÚÛÜÝÞß|
Ex|àáâãäåæçèéêëìíîï|
Fx|ðñòóôõö÷øùúûüýþÿ|
ISO mode can be enabled and disabled using two new control codes:
CHR$($0F)
: enable ISO modeCHR$($8F)
: enable PETSCII mode (default)You can also enable ISO mode in direct mode by pressing
Ctrl+O
.
Important: In ISO mode, BASIC keywords need to be written in upper case, that is, they have to be entered with the Shift key down, and abbreviating keywords is no longer possible.
In regular BASIC text mode, the video controller supports 16 foreground colors and 16 background colors for each character on the screen.
The new "swap fg/bg color" code is useful to change the background color of the cursor, like this:
PRINT CHR$(1); : REM SWAP FG/BG
PRINT CHR$($1C); : REM SET FG COLOR TO RED
PRINT CHR$(1); : REM SWAP FG/BG
The new BASIC instruction COLOR
makes this easier, but
the trick above can also be used from machine code programs.
To set the background color of the complete screen, it just has to be cleared after setting the color:
PRINT CHR$(147);
The C64 editor could only scroll the screen up (when overflowing the last line or printing or entering DOWN on the last line). The X16 editor scrolls both ways: When the cursor is on the first line and UP is printed or entered, the screen contents scroll down by a line.
This is the set of all supported PETSCII control characters. Entries in bold indicate new codes compared to the C64:
Code | Code | ||||
---|---|---|---|---|---|
$00 | NULL | VERBATIM MODE | $80 | ||
$01 | SWAP COLORS | COLOR: ORANGE | $81 | ||
$02 | PAGE DOWN/UP | $82 | |||
$03 | STOP/RUN | $83 | |||
$04 | END | HELP | $84 | ||
$05 | COLOR: WHITE | F1 | $85 | ||
$06 | MENU | F3 | $86 | ||
$07 | BELL | F5 | $87 | ||
$08 | BACKSPACE | F7 | $88 | ||
$09 | TAB | F2 | $89 | ||
$0A | LF | F4 | $8A | ||
$0B | - | F6 | $8B | ||
$0C | - | F8 | $8C | ||
$0D | REGULAR/SHIFTED RETURN | $8D | |||
$0E | CHARSET: LOWER/UPPER CASE | $8E | |||
$0F | CHARSET: ISO ON/OFF | $8F | |||
$10 | F9 | COLOR: BLACK | $90 | ||
$11 | CURSOR: DOWN/UP | $91 | |||
$12 | REVERSE ON/OFF | $92 | |||
$13 | HOME/CLEAR | $93 | |||
$14 | DEL/INSERT | $94 | |||
$15 | F10 | COLOR: BROWN | $95 | ||
$16 | F11 | COLOR: LIGHT RED | $96 | ||
$17 | F12 | COLOR: DARK GRAY | $97 | ||
$18 | SHIFT+TAB | COLOR: MIDDLE GRAY | $98 | ||
$19 | FWD DEL | COLOR: LIGHT GREEN | $99 | ||
$1A | - | COLOR: LIGHT BLUE | $9A | ||
$1B | ESC | COLOR: LIGHT GRAY | $9B | ||
$1C | COLOR: RED | COLOR: PURPLE | $9C | ||
$1D | CURSOR: RIGHT | CURSOR: LEFT | $9D | ||
$1E | COLOR: GREEN | COLOR: YELLOW | $9E | ||
$1F | COLOR: BLUE | COLOR: CYAN | $9F |
Notes:
GRAPH_put_char
.The editor supports multiple keyboard layouts.
On boot, the US layout (ABC/X16
) is active:
Key | Result |
---|---|
Alt+1 |
¡ |
Alt+3 |
£ |
Alt+4 |
¢ |
Alt+5 |
§ |
Alt+7 |
¶ |
Alt+9 |
ª |
Alt+0 |
º |
Alt+q |
œ |
Alt+r |
® |
Alt+t |
Þ |
Alt+y |
¥ |
Alt+o |
ø |
Alt+\ |
« |
Alt+s |
ß |
Alt+d |
ð |
Alt+g |
© |
Alt+l |
¬ |
Alt+' |
æ |
Alt+m |
µ |
Alt+/ |
÷ |
Shift+Alt+2 |
€ |
Shift+Alt+8 |
° |
Shift+Alt+9 |
· |
Shift+Alt+- |
\xad (SHY) |
Shift+Alt+= |
± |
Shift+Alt+q |
Œ |
Shift+Alt+t |
þ |
Shift+Alt+\ |
» |
Shift+Alt+a |
¹ |
Shift+Alt+d |
Ð |
Shift+Alt+' |
Æ |
Shift+Alt+c |
³ |
Shift+Alt+b |
² |
Shift+Alt+/ |
¿ |
The following combinations are dead keys:
6
e
u
p
a
k
;
x
c
v
n
,
.
S
They generate additional characters when combined with a second keypress:
First Key |
Second Key |
Result |
---|---|---|
Alt+` | a |
à |
Alt+` | e |
è |
Alt+` | i |
ì |
Alt+` | o |
ò |
Alt+` | u |
ù |
Alt+` | A |
À |
Alt+` | E |
È |
Alt+` | I |
Ì |
Alt+` | O |
Ò |
Alt+` | U |
Ù |
Alt+` | ␣ |
` |
Alt+6 |
e |
ê |
Alt+6 |
u |
û |
Alt+6 |
i |
î |
Alt+6 |
o |
ô |
Alt+6 |
a |
â |
Alt+6 |
E |
Ê |
Alt+6 |
U |
Û |
Alt+6 |
I |
Î |
Alt+6 |
O |
Ô |
Alt+6 |
A |
 |
Alt+e |
e |
é |
Alt+e |
y |
ý |
Alt+e |
u |
ú |
Alt+e |
i |
í |
Alt+e |
o |
ó |
Alt+e |
a |
á |
Alt+e |
E |
É |
Alt+e |
Y |
Ý |
Alt+e |
U |
Ú |
Alt+e |
I |
Í |
Alt+e |
O |
Ó |
Alt+e |
A |
Á |
Alt+u |
e |
ë |
Alt+u |
y |
ÿ |
Alt+u |
u |
ü |
Alt+u |
i |
ï |
Alt+u |
o |
ö |
Alt+u |
a |
ä |
Alt+u |
E |
Ë |
Alt+u |
Y |
Ÿ |
Alt+u |
U |
Ü |
Alt+u |
I |
Ï |
Alt+u |
O |
Ö |
Alt+u |
A |
Ä |
Alt+p |
␣ |
, |
Alt+a |
␣ |
¯ |
Alt+k |
a |
å |
Alt+k |
A |
Å |
Alt+x |
␣ |
. |
Alt+c |
c |
ç |
Alt+c |
C |
Ç |
Alt+v |
s |
š |
Alt+v |
z |
ž |
Alt+v |
S |
Š |
Alt+v |
Z |
Ž |
Alt+n |
o |
õ |
Alt+n |
a |
ã |
Alt+n |
n |
ñ |
Alt+n |
O |
Õ |
Alt+n |
A |
à |
Alt+n |
N |
Ñ |
Shift+Alt+s |
␣ |
\xa0 |
Shift+Alt+; |
= |
× |
"␣" denotes the space bar.
Pressing the F9
key cycles through the keyboard layouts
stored in ROM, in the following order:
Identifier | Description | Code |
---|---|---|
ABC/X16 |
ABC - Extended (X16) | - |
EN-US/INT |
United States - International | 00020409 |
EN-GB |
United Kingdom | 00000809 |
SV-SE |
Swedish | 0000041D |
DE-DE |
German | 00000407 |
DA-DK |
Danish | 00000406 |
IT-IT |
Italian | 00000410 |
PL-PL |
Polish (Programmers) | 00000415 |
NB-NO |
Norwegian | 00000414 |
HU-HU |
Hungarian | 0000040E |
ES-ES |
Spanish | 0000040A |
FI-FI |
Finnish | 0000040B |
PT-BR |
Portuguese (Brazil ABNT) | 00000416 |
CS-CZ |
Czech | 00000405 |
JA-JP |
Japanese | 00000411 |
FR-FR |
French | 0000040C |
DE-CH |
Swiss German | 00000807 |
EN-US/DVO |
United States - Dvorak | 00010409 |
ET-EE |
Estonian | 00000425 |
FR-BE |
Belgian French | 0000080C |
EN-CA |
Canadian French | 00001009 |
IS-IS |
Icelandic | 0000040F |
PT-PT |
Portuguese | 00000816 |
HR-HR |
Croatian | 0000041A |
SK-SK |
Slovak | 0000041B |
SL-SI |
Slovenian | 00000424 |
LV-LV |
Latvian | 00000426 |
LT-LT |
Lithuanian IBM | 00000427 |
All remaining keyboards are based on the respective Windows layouts.
EN-US/INT
differs from EN-US
only in Alt/AltGr
combinations and some dead keys.
The BASIC command KEYMAP
allows activating a specific
keyboard layout. It can be added to the auto-boot file, e.g.:
10 KEYMAP"NB-NO"
SAVE"AUTOBOOT.X16
The tables for the active keyboard layout reside in banked RAM, at $A000 on bank 0:
Adresses | Description |
---|---|
$A000-$A07F | Table 0 |
$A080-$A0FF | Table 1 |
$A100-$A17F | Table 2 |
$A180-$A1FF | Table 3 |
$A200-$A27F | Table 4 |
$A280-$A07F | Table 5 |
$A300-$A37F | Table 6 |
$A380-$A3FF | Table 7 |
$A400-$A47F | Table 8 |
$A480-$A4FF | Table 9 |
$A500-$A57F | Table 10 |
$A580-$A58F | big-endian bitfield: PS/2 scancodes for which Caps means Shift |
$A590-$A66F | dead key table |
$A670-$A67E | ASCIIZ identifier (e.g. "ABC/X16") |
The first byte of each of the 11 tables is the table ID which contains the encoding and the combination of modifiers that this table is for.
Bit | Description |
---|---|
7 | 0: PETSCII, 1: ISO |
6-3 | always 0 |
2 | Ctrl |
1 | Alt |
0 | Shift |
The identifier is followed by 127 output codes for the scancode inputs 1-127.
Keys with $E0/$E1-prefixed PS/2 scancodes (cursor keys etc.) are hardcoded and cannot be changed using these tables.
The dead key table has one section for every dead key with the following layout:
Byte | Description |
---|---|
0 | dead key ID (PETSCII/ISO and Shift/Alt/Ctrl) |
1 | dead key scancode |
2 | full length of this table in bytes |
3 | first additional key ISO code |
4 | first effective key ISO code |
5 | second additional key ISO code |
6 | second effective key ISO code |
... | ... |
n-1 | terminator 0xFF |
Custom layouts can be loaded from disk like this:
LOAD"KEYMAP",8,0,$A000
Here is an example that activates a layout derived from "ABC/X16", with unshifted Y and Z swapped in PETSCII mode:
100 KEYMAP"ABC/X16" :REM START WITH DEFAULT LAYOUT
110 POKE0,0 :REM ACTIVATE RAM BANK 0
120 FORI=0TO11:B=$A000+128*I:IFPEEK(B)<>0THENNEXT :REM SEARCH FOR TABLE $00
130 POKEB+$1A,ASC("Y") :REM SET SCAN CODE $1A ('Z') to 'Y'
140 POKEB+$35,ASC("Z") :REM SET SCAN CODE $35 ('Y') to 'Z'
170 REM
180 REM *** DOING THE SAME FOR SHIFTED CHARACTERS
190 REM *** IS LEFT AS AN EXERCISE TO THE READER
If you need more control over the translation of scancodes into PETSCII/ISO codes, or if you need to intercept any key down or up event, you can hook the custom scancode handler vector at $032E/$032F.
On all key down and key up events, the keyboard driver calls this vector with
The handler has to return a key event the same way in .X/.A/.C.
kbdbuf_put
KERNAL API.You can even write a completely custom keyboard translation layer:
kbdbuf_put
to store it in the keyboard buffer.;EXAMPLE: A custom handler that prints "A" on Alt key down
setup:
sei
lda #<keyhandler
sta $032e
lda #>keyhandler
sta $032f
cli
rts
keyhandler:
php ;Save input on stack
pha
phx
bcs exit ;C=1 is key up
cmp #$11 ;Alt key scancode
bne exit
lda #'a'
jsr $ffd2
exit:
plx ;Restore input
pla
plp
rts