RCA CDP18S711 manual The Power Supply

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RCA COSMAC VIP Instruction Manual

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RCA COSMAC VIP Instruction Manual

CHIP-8 includes a real time clock, random number generator, decimal conversion, and digit or graphic display capability. It only uses 512 bytes of RAM leaving over 1024 bytes for programs in a 2048-byte system. (You can get an additional 2048 bytes of RAM by plugging four more RAM chips into your card.)

With the aid of the User Manual for the CDPI802 COSMAC Microprocessor, MPM-201, you can explore the fascinating world of machine language programming. You can even combine, machine language programs with CHIP-8 programs or develop your own interpretive languages.

For hardware hackers, COSMAC VIP provides complete external interface capabilities. Some suggestions for inexpensive external devices and applications are listed in Section VI. Logic diagrams, data sheets, trouble -shooting hints, and test programs are provided so that you can explore the hardware in as much detail as you want.

This manual assumes that you are familiar with computer basics from reading one or more of the excellent magazines devoted to home computing. You should understand RAM, ROM, memory addressing, instructions, bytes, etc. The use of a scope

will facilitate setting up the cassette system and iden- tifying hardware problems in the rare case where they occur. Hex notation is used in this manual unless noted otherwise. (One byte equals two hex digits.)

The Power Supply

The output wires of the internally regulated power converter supplied with the COSMAC VIP CDP18S711 are connected to the +V DC and GND pads at the back left comer of the PC card. The power converter output is regulated +5 V DC at 600 mA. If you wish to add more RAM to your system, however, you may need a higher-current power supply. A 2048-byte system requires about 350 mA (600 mA worst case). A 4096-byte system should require average current of about 600 mA. If, however, your RAM chips require above average power, you may need to supply as much as 900 mA at 5 V DC, regulated. You can also use your own unregulated 8 to 10 V DC power supply by adding voltage regulator U28 (plus heatsink) to your COSMAC VIP card and cutting the printed circuit link called LKI. Never apply more than +5 V DC to the card unless the U28 regulator has been added and link LKI cut.

Photograph of COSMAC VIP (Video Interface Processor) CDP18S711 The cables in the upper right are for the video display and for cassette operation. Cable on the upper left goes to the power converter.

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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 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 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 No Sound VIL Troubleshooting HintsOther Problems Signal TracingLast 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 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
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