h6. [[Programmer's Reference Manuals]] h6(. » VDU Codes h2. VDU Codes 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. table(bordered). |_\2~={width:12em}. VDU code|_/2~<{width:3em}. Ctrl plus|_/2~<{width:4em}. Extra bytes|_/2~<{width:30em}. Meaning| |_~<{width:7em}. #|_~<{width:5em}. # Hex| |<^(#0). 0|<^. &00|<^. @|<^. 0|<^. Does nothing| |<^(#1). 1|<^. &01|<^. A|<^. 1|<^. Sends next character to printer only| |<^(#2). 2|<^. &02|<^. B|<^. 0|<^. Enables printer| |<^(#3). 3|<^. &03|<^. C|<^. 0|<^. Disables printer| |<^(#4). 4|<^. &04|<^. D|<^. 0|<^. Writes text at text cursor| |<^(#5). 5|<^. &05|<^. E|<^. 0|<^. Writes text at graphics cursor| |<^(#6). 6|<^. &06|<^. F|<^. 0|<^. Enables VDU driver| |<^(#7). 7|<^. &07|<^. G|<^. 0|<^. Generates bell sound| |<^(#8). 8|<^. &08|<^. H|<^. 0|<^. Moves cursor back one character| |<^(#9). 9|<^. &09|<^. I|<^. 0|<^. Moves cursor forward one character| |<^(#10). 10|<^. &0A|<^. J|<^. 0|<^. Moves cursor down one line| |<^(#11). 11|<^. &0B|<^. K|<^. 0|<^. Moves cursor up one line| |<^(#12). 12|<^. &0C|<^. L|<^. 0|<^. Clears text window/form feed| |<^(#13). 13|<^. &0D|<^. M|<^. 0|<^. Carriage return (moves cursor to start of subsequent line)| |<^(#14). 14|<^. &0E|<^. N|<^. 0|<^. Turns on paged mode| |<^(#15). 15|<^. &0F|<^. O|<^. 0|<^. Turns off paged mode| |<^(#16). 16|<^. &10|<^. P|<^. 0|<^. Clears graphics window| |<^(#17). [[VDU 17|17]]|<^. &11|<^. Q|<^. 1|<^. [[VDU 17|Defines text colour]]| |<^(#18). [[VDU 18|18]]|<^. &12|<^. R|<^. 2|<^. [[VDU 18|Defines graphics colour]]| |<^(#19). [[VDU 19|19]]|<^. &13|<^. S|<^. 5|<^. [[VDU 19|Defines logical colour]]| |<^(#20). 20|<^. &14|<^. T|<^. 0|<^. Restores default logical colours| |<^(#21). 21|<^. &15|<^. |<^. 0|<^. Disables VDU drivers| |<^(#22). 22|<^. &16|<^. V|<^. 1|<^. Selects screen mode| |<^(#23). 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). [[VDU 24|24]]|<^. &18|<^. X|<^. 8|<^. [[VDU 24|Defines graphics window]] | |<^(#25). [[VDU 25|25]]|<^. &19|<^. Y|<^. 5|<^. [[VDU 25|PLOT command]]| |<^(#26). 26|<^. &1A|<^. Z|<^. 0|<^. Restores default windows| |<^. 27|<^. &1B|<^. [|<^. 0|<^. Does nothing| |<^(#28). [[VDU 28|28]]|<^. &1C|<^. \|<^. 4|<^. [[VDU 28|Defines text window]]| |<^(#29). [[VDU 29|29]]|<^. &1D|<^. ]|<^. 4|<^. [[VDU 29|Defines graphics origin]]| |<^(#30). 30|<^. &1E|<^. ^|<^. 0|<^. Homes text cursor| |<^(#31). [[VDU 31|31]]|<^. &1F|<^. _|<^. 2|<^. [[VDU 31|Moves text cursor]]| |<^. 127|<^. &7F|<^. |<^. 0|<^. Delete|