LARGE adds a command for printing text at any size and at any pixel position. After the code is installed, PRINT USR large;AT X,Y;W,H;"text" prints the text with its top-left corner at pixel column X (0–255) and line Y (0–191), each letter W characters wide and H characters high. The text can be a quoted string or a string variable, and PAPER, INK and FLASH work inside the PRINT as usual. The demonstration prints “2068 LARGE print” again and again at random sizes, places and colours.
LARGE was the type-in in Michael J. Di Rienzo’s “Mike’s Notebook” column in RMG Enterprises’ April 1991 UPDATE disk magazine, which also says this was the column’s last regular appearance. The listing here was typed from that column; its DATA total matches the column’s checksum, 31728.
Program Analysis
Structure
Lines 10–90 are the demonstration. Lines 100–140 clear memory to 59399, POKE the 350 bytes of DATA (lines 150–190) into 60400–60749 with a checksum test, and RUN the demonstration. As the column says, run line 100 first; this tape starts there automatically.
Notable Techniques
- The routine is called as a function inside
PRINT, so it can parse the rest of the statement itself: it checks for theATtoken and the separators and reports “Nonsense in BASIC” on a syntax error. - Text that runs off the screen wraps around to the opposite side, so long strings need planning.
The code is not relocatable. The program was tested in ZEsarUX: the code installs, the checksum passes and the demonstration prints at random sizes.
Image Gallery
Source Code
10 BORDER 0: PAPER 0: INK 7: CLS : OUT 254,1: LET large=60400
20 LET d$="2068 LARGE print"
30 RANDOMIZE
40 LET w=INT (1+RND*2)
50 LET h=INT (1+RND*12)
60 LET x=INT (RND*(256-(w*8*16)))
70 LET y=INT (RND*(192-(h*8)))
80 LET i=INT (1+RND*6)
90 PRINT INK i;USR large;AT x,y;w,h;d$: PAUSE 100: CLS : GO TO 40
100 CLEAR 59399: LET t=0
110 FOR n=60400 TO 60749
120 READ a: POKE n,a: LET t=t+a
130 NEXT n: IF t<>31728 THEN PRINT FLASH 1;"Data Error!": PRINT "Recheck DATA lines": STOP
140 RUN
150 DATA 17,117,33,225,167,237,82,32,250,213,223,254,59,32,40,231,254,172,32,35,205,220,27,205,96,38,237,67,10,91,223,254,59,32,20,205,220,27,205,96,38,237,67,12,91,62,8,50,14,91,223,254,59,40,2,207,11,231,205,239,27,205,175,47,33,15,91,235,237,176,62,255,18
160 DATA 33,15,91,126,35,34,0,91,111,60,200,38,0,41,41,41,237,75,54,92,9,62,8,50,4,91,58,11,91,50,9,91,58,10,91,50,8,91,62,9,50,5,91,126,35,34,2,91,7,50,6,91,58,5,91,61,32,50,58,4,91,61,32,24,58,14
170 DATA 91,71,58,12,91,79,58,10,91,129,5,32,252,50,10,91,42,0,91,195,60,236,50,4,91,58,13,91,71,58,9,91,128,50,9,91,42,2,91,195,89,236,50,5,91,58,12,91,71,58,9,91,50,7,91,58,13,91,79,197,205,221,236,193,58,7
180 DATA 91,60,50,7,91,13,32,241,58,8,91,60,50,8,91,5,32,221,58,6,91,195,105,236,128,64,32,16,8,4,2,1,58,142,92,238,255,71,58,143,92,160,71,58,8,91,230,248,111,58,7,91,254,192,208,31,31,31,230,31,103,203,28,203,29,203,28,203,29,203,28,203,29,62,88,180
190 DATA 103,58,142,92,166,176,119,58,7,91,71,230,7,246,64,103,120,31,31,31,230,24,180,103,120,23,23,230,224,111,58,8,91,71,31,31,31,230,31,181,111,235,33,213,236,120,230,7,79,6,0,9,70,26,33,6,91,203,70,40,3,176,18,201,47,176,47,18,201Note: Type-in program listings on this website use ZMAKEBAS notation for graphics characters.