RCA CDP18S711 manual CHIP-8Memory Map, CDP1802 Register Use for CHIP-8, Interpreter

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36RCA COSMAC VIP Instruction Manual

36RCA COSMAC VIP Instruction Manual

CHIP-8 Memory Map	CDP1802 Register Use for CHIP-8
	Interpreter
	R0	= DMA pointer (page 0X for display refresh)
	R1	= INTERRUPT routine program counter
	R2	= Stack pointer
	R3	= INTERPRETER subroutine program counter
	R4	= CALL subroutine program counter
	R5	= CHIP-8 instruction program counter
	R6	= VX pointer (R6.1 must not be changed)
	R7	= VY pointer (available for machine-language subroutines)
	R8	= Timers (R8.1 = timer, R8.0 = tone duration)
	R9	= Random number (+1 in INTERRUPT routine)
	RA = I pointer

RB = Display page pointer (RB.1 = 0X)

RC =Available

RD = Available

RE = Available

RF = Available

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Contents Page VIP-311 RCA COSMAC VIP CDP18S711 Instruction ManualACKNOWLEDGMENT Contents Contents Continued What This Manual Covers 1. Getting StartedThe Power Supply 1. Getting Started What You SeeTurning It On Memory Write Using the Operating System11.COSMAC VIP Operation Tape Read Memory ReadTape Write 11.COSMAC VIP Operation Testing Your Cassette SystemBranch Instructions How to Change and Use the VariablesIII.CHIP-8Language Programming Using the Display Instructions 020C F090 020E F000 III. CHIP-8 Language Programming0200 A20A I=020A 0202 6100 V1=00 0204 6200 V2=00 0206 D125 SHOW 5MI@VlV2 0208 1208 GO 020A F090Applying CHIP-8 111. CHIP-8Language Programming Some Program Ideas25.PROGRAMMED SPOT - Introduce children to programming concepts by letting them preprogram the movements of a spot or object on the screen VIP Machine Coding IV. Machine Language ProgrammingMachine Language Programming Summed Up How the Input/Output Works V. Logic DescriptionHow Memory Is Addressed pressed. A 62 machine instruction causes the least significant 4 bits of memory byte to be latched into U13. These 4 bits are decoded to bring one of the 16 U13 output lines low. If the key that corresponds to this output line is pressed, the CDPI802 EF3 input will go low. The 4-bitcodes latched into U13 correspond to the equivalent key positions. After the program send8 a 4-bitcode to U13, it subsequently examines the EF3 line to see if the key corresponding to this code is pressed or not. In this manner, a program can determine when any specific key is pressed or can sequentially scan all keys while waiting for any one to be pressed. Key debounce delays must be provided in the program when required. A program can also cause a speaker tone to occur when a key is pressed. Only one key at a time should be pressed with this method of interfacing the keyboard V1. Expansion Considerations and Connections Using the Byte Input/OutputI RCA COSMAC VIP Instruction Manual Using the Expansion InterfaceSome Expansion Ideas Table III - External Option Terminal Connections Pin SignalV1. Expansion Considerations and Connections 2.Composing poetry or pictures with printer output No Sound VIL Troubleshooting HintsOther Problems Signal TracingLast Resorts Beeper Program Appendix A - Test and Operating DataByte Pattern for Displaying COSMAC Test Program Cassette Attachment Diagram Cassette Phase TestSignals Cassette Data Test Memory Test Program Cassette Recording GuidelinesOperating System Listing Appendix B - Operating SystemR3 = Machine Language Subroutine Program Counter Operating System Register TableOperating System Summary CHIP-8Interpreter Listing Appendix C - CHIP-8InterpreterInterpreter CHIP-8Memory MapCDP1802 Register Use for CHIP-8 Appendix C - CHIP-8Interpreter RCA COSMAC VIP Instruction Manual CHIP-8User NotesPage 1. VIP Kaleidoscope 2. VIP Video Display Drawing Game Circuits Appendix E - Logic DiagramsFig. E-5Power Supply Circuit and Byte Fig. E-1Microprocessor and Display InterfacePage Appendix E - Logic Diagrams Fig. E-2- ROM Circuits and Expansion InterfacePage Appendix E - Logic Diagrams Fig. E-4- RAM CircuitsRCA COSMAC VIP Instruction Manuel RCA COSMAC VIP Instruction Manual 1.Printed Circuit Board Layout Board Layout, Parts List, and Expansion NotesAppendix F 2.Parts List for RCA COSMAC VIP CDP18S711RCA COSMAC VIP Instruction Manual Page 2. Parts List for RCA COSMAC VIP CDP18S711 Page Resistors - Supplied 1 /4 W except as noted RCA COSMAC VIP Instruction ManualPage 3. COSMAC VIP Expansion Notes