RCA CDP18S711 manual CHIP-8User Notes, RCA COSMAC VIP Instruction Manual

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RCA COSMAC VIP Instruction Manual

CHIP-8 User Notes

1Do not use any of the CDP1802 three-cycle machine language instructions in CHIP-8 programs.

2.CDP1802 R5 is used as the CHIP-8 instruction counter. It will he addressing the byte following a 0MMM instruction for machine language subroutines and can be used to pass 2-byte parameters. Refer to the operating system register table in Appendix B to examine this register during CHIP-8 program debugging.

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5.R7, RC, RD, RE, and RF can be used as working registers in machine language subroutines. Changing other registers can cause the CHIP-8 interpreter to malfunction.

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7.Program bugs can destroy the CHIP-8 in- terpreter at locations 0000-01FF. If you suspect that this has happened, reload the interpreter.

8.The CHIP-8 interpreter uses subroutines and digit patterns contained in the operating system ROM. If you modify this operating system, the CHIP-8 interpreter should not be used.

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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 Turning It On What You See1. Getting Started 11.COSMAC VIP Operation Using the Operating SystemMemory Write Tape Write Memory ReadTape Read 11.COSMAC VIP Operation Testing Your Cassette SystemIII.CHIP-8Language Programming How to Change and Use the VariablesBranch Instructions Using the Display Instructions 0200 A20A I=020A 0202 6100 V1=00 0204 6200 V2=00 III. CHIP-8 Language Programming0206 D125 SHOW 5MI@VlV2 0208 1208 GO 020A F090 020C F090 020E F000Applying 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 Memory Is Addressed V. Logic DescriptionHow the Input/Output Works 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/OutputSome Expansion Ideas Using the Expansion InterfaceI RCA COSMAC VIP Instruction Manual V1. Expansion Considerations and Connections Pin SignalTable III - External Option Terminal Connections 2.Composing poetry or pictures with printer output Other Problems VIL Troubleshooting HintsSignal Tracing No SoundLast Resorts Byte Pattern for Displaying COSMAC Appendix A - Test and Operating DataBeeper Program Signals Cassette Attachment Diagram Cassette Phase TestTest Program Cassette Data Test Memory Test Program Cassette Recording GuidelinesOperating System Listing Appendix B - Operating SystemOperating System Summary Operating System Register TableR3 = Machine Language Subroutine Program Counter CHIP-8Interpreter Listing Appendix C - CHIP-8InterpreterCDP1802 Register Use for CHIP-8 CHIP-8Memory MapInterpreter Appendix C - CHIP-8Interpreter RCA COSMAC VIP Instruction Manual CHIP-8User NotesPage 1. VIP Kaleidoscope 2. VIP Video Display Drawing Game Fig. E-5Power Supply Circuit and Byte Appendix E - Logic DiagramsFig. E-1Microprocessor and Display Interface CircuitsPage 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 Appendix F Board Layout, Parts List, and Expansion Notes2.Parts List for RCA COSMAC VIP CDP18S711 1.Printed Circuit Board LayoutRCA 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