RCA CDP18S711 manual VIP Kaleidoscope

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1. VIP Kaleidoscope

This program uses the CHIP-8 INTERPRETER at

0000-01FF. Four spots appear in a group at the center of the screen. Press keys 2, 4, 6, or 8 to create a pattern. Keep your pattern smaller than 138 key depressions. Push key 0 to terminate pattern

RCA COSMAC VIP Instruction Manual

entry. Pushing key 0 causes your pattern to be continuously repeated forming a fascinating, changing kaleidoscope display on the screen. A "44444442220" key sequence provides a very nice effect Experiment to find other nice patterns. The subroutine at 0232-0274 causes your pattern to be duplicated in the four quadrants of the screen.

0200	6000	V0=00	023C	7101	V1+01
0202	6380	V3=80	023E	4008	SKIP;V0 NE 08
0204	611F	V1=1F	0240	7201	V2+01
0206	620F	V2=0F	0242	A277	I=0277
0208	2232	DO 0232	0244	6AEO VA=E0
020A	A200	I=0200	0246	8A12	VA=VA&Vl
020C	F31E I=I+V3		0248	6B1F VB=1F
020E	F00A V0=KEY		024A	81B2	VI=Vl&VB
0210	F055	MI-V0:V0	024C	3AOO SKIP;VA EQ 00
0212	4000	SKIP;V0 NE 00	024E	7201	V2+01
0214	121C	GO 021C	0250	6AFO VA=FO
0216	7301	V3+01	0252	8A22	VA=VA&V2
0218	3300	SKIP;V3 EQ 00	0254	6BOF VB=OF
021A	1208	GO 0208	0256	8282	V2=V2&VB
021C	6380	V3=80	0258	3AOO SKIP; VAEQ 00
021E	A200	I=0200	025A	7101	V1+01
0220	F31E I=I+V3		025C	6BIF VB=1F
0222	F065	VO:VO=MI	025E	81B2	Vl=Vl&VB
0224	4000	SKIP;VO NE 00	0260	D121	SHOW 1MI@VlV2
0226	121C	GO 021C	0262	8A10	VA=Vl
0228	7301	V3+01	0264	6B1F VB=1F
022A	4300	SKIP;V3 NE 00	0266	8B25	VB=VB-V2
022C	121C	GO 021C	0268	DAB1 SHOW 1MI@VAVB
022E	2232	DO 0232	026A	6A3F VA=3F
0230	121E	GO 021E	026C	8A15	VA=VA-VI
0232	4002	SKIP;V0 NE 02	026E	DABI SHOW 1MI@VAVB
0234	72FF V2+FF		0270	8B20	VB=V2
0236	4004	SKIP;VO NE 04	0272	DAB1 SHOW 1MI@VAVB
0238	71FF VI+FF		0274	00EE RET
023A	4006	SKIP;V0 NE 06	0276	0180
			0278	0000