split: add some split-screen demos

split_screen/Makefile

@@ -0,0 +1,26 @@
+include ../Makefile.inc
+
+DOS33 = ../dos33fs-utils/dos33
+TOKENIZE = ../asoft_basic-utils/tokenize_asoft
+
+all:	split.dsk
+
+split.dsk:	BISHOP BISHOP.BAS RAINBOW.BAS
+	$(DOS33) -y split.dsk BSAVE -a 0x0300 BISHOP
+	$(DOS33) -y split.dsk SAVE A BISHOP.BAS
+	$(DOS33) -y split.dsk SAVE A RAINBOW.BAS
+
+BISHOP:	bishop.o
+	ld65 -o BISHOP bishop.o -C ../linker_scripts/apple2_300.inc
+
+bishop.o:	bishop.s
+	ca65 -o bishop.o bishop.s -l bishop.lst
+
+BISHOP.BAS:	bishop.bas
+	$(TOKENIZE) < bishop.bas > BISHOP.BAS
+
+RAINBOW.BAS:	rainbow.bas
+	$(TOKENIZE) < rainbow.bas > RAINBOW.BAS
+
+clean:	
+	rm -f *~ *.o *.lst BISHOP

split_screen/bishop.bas

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+' Bob Bishop screen splitting demo 
+' Softalk, October 1982
+' See http://rich12345.tripod.com/aiivideo/softalk.html
+10 PRINT CHR$(4)"BLOAD BISHOP"
+100 HOME
+200 FOR K = 0 TO 39
+210 POKE 1448 + K, 14 * 16
+220 POKE 2000 + K, 10 * 16
+230 COLOR= K + 4
+240 VLIN 25,45 AT K
+250 NEXT K
+300 VTAB 6: HTAB 17
+310 PRINT "APPLE II"
+400 CALL 768
+500 GOTO 400

split_screen/bishop.s

@@ -0,0 +1,19 @@
+	STA $C052
+	LDA #$E0
+l0305:
+	LDX #$04
+l0307:
+	CMP $C051
+	BNE l0305
+	DEX
+	BNE l0307
+	LDA #$A0
+l0311:
+	LDX #$04
+l0313:
+	CMP $C050
+	BNE l0311
+	DEX
+	BNE l0313
+	STA $C051
+	RTS

split_screen/rainbow.bas

@@ -0,0 +1,22 @@
+10 A = 9200 :B = 13168:C=100:X=279
+20 TEXT : HOME :GOTO 40
+30 HPLOT 0,Y TO X,Y:RETURN
+40 DATA 173,87,192,173,83,192,173,84,192,173,80,192
+50 DATA 208,251,173,86,192,160,22,136,208,253,234,173,87,192,76,9,3
+60 FOR I = 768 TO 796:READ N:POKE I,N:NEXT
+70 HGR : POKE  - 16302,0
+80 HCOLOR= 4:HPLOT 0,0: CALL 62454
+90 HCOLOR= 2:Y=63:GOSUB 30:Y=62:GOSUB 30
+100 HCOLOR= 6:Y=61:GOSUB 30:Y=60:GOSUB 30
+110 HCOLOR= 1:Y=59:GOSUB 30:Y=58:GOSUB 30
+120 HCOLOR= 5:Y=55:GOSUB 30:Y=54:GOSUB 30
+130 HCOLOR= 0:X=C
+140 Y=123:GOSUB 30:Y=122:GOSUB 30
+150 Y=119:GOSUB 30:Y=118:GOSUB 30
+160 COLOR= 0:FOR I = 0 TO 39:VLIN 0,39 AT I:NEXT
+170 COLOR= 13:HLIN 0,39 AT 14
+180 FOR I = 0 TO 7:POKE A + I,0:POKE B + I,0:NEXT
+190 COLOR= 1:HLIN 0,39 AT 13
+200 VTAB 21:PRINT TAB(16)"RAINBOW"
+210 PRINT:PRINT "MIXED GRAPHICS (HI-RES/COLOR)"
+220 CALL 768