Showing changes from revision #7 to #8:
Added | Removed | Changed
A table below lists the VDU codes and their meanings. Some VDU codes require parameters sending as extra bytes; e.g. VDU 22 (select screen mode) requires the screen mode passing as a parameter (one extra byte). The number of extra bytes required is also listed.
VDU code | Ctrl plus | Extra bytes | Meaning | ||||
---|---|---|---|---|---|---|---|
# | # Hex | Ctrl plus | Extra bytes | Meaning | |||
0 | &00 | @ | 0 | Does nothing | |||
1 | &01 | A | 1 | Sends next character to printer only | |||
2 | &02 | B | 0 | Enables printer | |||
3 | &03 | C | 0 | Disables printer | |||
4 | &04 | D | 0 | Writes text at text cursor | |||
5 | &05 | E | 0 | Writes text at graphics cursor | |||
6 | &06 | F | 0 | Enables VDU driver | |||
7 | &07 | G | 0 | Generates bell sound | |||
8 | &08 | H | 0 | Moves cursor back one character | |||
9 | &09 | I | 0 | Moves cursor forward one character | |||
10 | &0A | J | 0 | Moves cursor down one line | |||
11 | &0B | K | 0 | Moves cursor up one line | |||
12 | &0C | L | 0 | Clears text window/form feed | |||
13 | &0D | M | 0 | Carriage return (moves cursor to start of subsequent line) | |||
14 | &0E | N | 0 | Turns on paged mode | |||
15 | &0F | O | 0 | Turns off paged mode | |||
16 | &10 | P | 0 | Clears graphics window | |||
17 | &11 | Q | 1 | Defines text colour | |||
18 | &12 | R | 2 | Defines graphics colour | |||
19 | &13 | S | 5 | Defines logical colour | |||
20 | &14 | T | 0 | Restores default logical colours | |||
21 | &15 | 0 | Disables VDU drivers | ||||
22 | &16 | V | 1 | Selects screen mode | |||
23 | &17 | W | 9 | Multi-purpose command: | |||
23,0 | Sets the interlace and controls cursor appearance | ||||||
23,1 | Controls text cursor appearance | ||||||
23,2-5 | Defines ECF pattern and colours | ||||||
23,6 | Sets dot-dash line style | ||||||
23,7 | Scrolls text window or screen | ||||||
23,8 | Clears a block of the text window | ||||||
23,9 | Sets first flash time | ||||||
23,10 | Sets second flash time | ||||||
23,11 | Sets default patterns | ||||||
23,12-15 | Defines simple ECF patterns and colours | ||||||
23,16 | Controls cursor movement after printing | ||||||
23,17,0-3 | Sets the tint for a colour | ||||||
23,17,4 | Chooses ECF patterns | ||||||
23,17,5 | Exchanges text foreground and background colours | ||||||
23,17,6 | Sets ECF origin | ||||||
23,17,7 | Sets character size/spacing | ||||||
23,18-24 | Reserved for future expansion | ||||||
23,25-26 | Private Font Manager calls | ||||||
23,27 | Private Sprite Manager calls | ||||||
23,28-31 | Reserved for use by application programs | ||||||
23,32-255 | Redefines printable characters | ||||||
24 | &18 | X | 8 | Defines graphics window | |||
25 | &19 | Y | 5 | PLOT command | |||
26 | &1A | Z | 0 | Restores default windows | |||
27 | &1B | [ | 0 | Does nothing | |||
28 | &1C | \ | 4 | Defines text window | |||
29 | &1D | ] | 4 | Defines graphics origin | |||
30 | &1E | ^ | 0 | Homes text cursor | |||
31 | &1F | _ | 2 | Moves text cursor | |||
127 | &7F | 0 | Delete |