0 'Club 100 Library, Modem 415-939-1246
1 'SCROLL.200 by James Yi 8/27/86
2 'Scroll up dot by dot
100 FORL=0TO25:PRINT@600,:NEXT:'Clear screen
110 S=PEEK(65196)+PEEK(65197)*256:'Top left Screen position
120 S=(S+3072)MOD8192:'Make line 0 appear at line 17
130 FORL=0TO7:'Scroll 8 rows at a time
140 IFINKEY$<>""GOTO230
150 IF L=0THENREADM$:IFM$="end"GOTO220ELSEPRINT@0,M$+SPACE$(40-LEN(M$));:GOTO170:'Print a line of message
160 FORW=0TO48:NEXT
170 S=S+40:S=SMOD8192:A=S-INT(S/256)*256:B=S/256:'Add 40(40 bytes in a line) to the pointer
180 OUT255,8:OUT254,A:OUT255,9:OUT254,B:'Send this value to the LCD
190 NEXT:'Completely scroll up a character
200 P=PEEK(65196)+PEEK(65197)*256:P=(P+320)MOD8192:A=P-INT(P/256)*256:B=P/256:POKE65196,A:POKE65197,B:'Next print position
210 GOTO130
220 RESTORE:GOTO150
230 OUT255,8:OUT254,PEEK(65196):OUT255,9:OUT254,PEEK(65197):END:'Return to normal position
240 DATA As you can see screen scrolls up dot by,dot.  The trick is done by assigning
250 DATAdifferent values to the screen locator,of the Tandy 200's LCD unit.  It can be,altered so that any one of 8 byte
260 DATAportion of any character on any position,on the screen can be displayed anywhere,else without moving it.
270 DATA The position of the byte that is,displayed at the top left corner of the,screen is in addresses 65196 and 65197.
280 DATA  There are 8192 bytes of graphics data,in LCD and any one byte can take the
290 DATAtop left corner position by sending a,value of 0 to 8191 via OUT statement,                                      .
300 DATAEnter your own message in data lines,A line consists of 40 characters.
310 DATA Press any key to end.,----------------------------------------
320 DATA end