INTRODUCTION The Hewlett-Packard 2100A Computer is a compact data processor featuring a powerful, extended instruction set, plug-in interfaces, and modular software. Standard features include memory parity generation and checking, memory and I/O protect for executive systems, extended arithmetic capability, and power fail interrupt with automatic restart. Optional features include two-channel di- rect memory access, multiplexed input/output, a controller panel, and the I/O interfaces. The controller panel, which provides a mini- mum of controls and indicators, is available for applications where the full complement of controls and indicators provided on the operator panel is not necessary. The logical design and software follow conventional standards of computer usage and notation so that the 2100A may be used as a free-standing device or in systems such as process control, media conversion, data reduction, communications, or time-sharing. [PHOTO] Figure 1.1 Hewlett-Packard 2100A Computer 1-1 Memory * Magnetic core storage * 980 nanosecond cycle time * Parity generation and checking is standard in all units * Six memory sizes available, 4096 to 32768 words; field-expandable by plug-in cards * 1024-word page size * Protected 64-word block for stored loader Processor * 80 basic instructions, including extended arithmetic * Up to eight instructions may be combined into one word (register reference group) * Two accumulators, addressable as memory locations * Unlimited levels of indirect addressing allowed * Six working registers, may be selected for display and instant modification (A,B,T,P,M,S) * Illuminated control pushbuttons allow simultaneous display and control of internal functions * All instructions fully executed in 1.96 microseconds, except ISZ and extended arithmetic (2.94 to 16.7 microseconds) * Only 980 nanoseconds added for each level of indirect addressing * Memory and I/O protection is standard Software * FORTRAN, FORTRAN IV, ALGOL, and BASIC languages * Extended Assembly language * Editor, subroutine library, Formatter, and Debug routine * Several operating systems, including: Basic Control System Magnetic Tape System Disc Operating System Time-Shared BASIC System Input/Ouput System * 14 Internal I/O channels, externally expandable to 45 * Optional multiplexed I/O extends capability to 56 channels; may be plugged into any slot * All channels buffered and bi-directional * Multilevel priority interrupt for device servicing * Peripherals interfaced simply with plug-in cards * Optional dual-channel direct memory access, can transfer 1,020,400 words per second * General-purpose interface cards available Table 1.1. 2100A General Specifications 1-2 Peripherals * Magnetic Tape Read and write 9-track IBM-compatible magnetic tape, 800 and 1600 cpi, at speeds of 25, 37.5, or 45 inches per second; also read and write 7-track IBM-compatible magnetic tape at speeds of 25, 37.5, or 45 inches per second with switch-selectable densities of 200, 556, and 800 cpi. * Disc Memory Fixed head-per-track design for rapid access, capacities range from 262,144 to 1,048,576 words * Cartridge Disc Moving-head disc for low-cost mass storage; capacities range from 2.5 million to 4.9 million bytes * Disc File Moving head mass storage; 11.7 million words per drive, 8 drives maximum * Card Reader Reads punched 80-column cards, 12 bits in parallel, at 1000 cards per minute * Mark Reader Reads punched and pencil-marked cards at 200 cards per minute * Line Printers Print 120 or 132 columns per line at 300 or 600 lines per minute; ASCII 64-character set. Also from 356 lines per minute (80 columns) to 1110 lines per minute (20 columns); 64-character set * Keyboard Display Terminal CRT screen displays 25 lines, 72 characters per line; standard tele- printer keyboard plus 10-key numerical keyboard; speeds of 10 to 200 characters per second, switch selectable * Tape Readers Read 5- and 8-level punched paper tape at up to 500 characters per second; with or without automatic reroller * Tape Punch Punches 5- and 8-level code at 120 characters per second; also 5- and 8-level code at 75 characters per second Table 1.2. 2100A Peripherals 1-3 [PHOTO] HP 7900 [PHOTO] HP 7901 Figure 1.2. The HP 7900 and 7901 Cartidge Disc Drives allow the 2100 user to economically and efficiently add on-line mass storage capability. The 7900 provides 4.9 million bytes of storage and an average access time of 30 milliseconds. 1-4 1.1 INTERFACING Interfacing of peripheral devices is accomplished by plug-in inter- face cards. The computer mainframe can accommodate up to 14 interface cards, expandable to a total of 45 when the optional 2155A I/O Extender is used. Interrupt and addressing capabilities are present for 56 channels so that, using multiplexed I/O and an external controller, up to 56 devices can be handled. Interface cards are available for a wide variety of peripheral devices, and virtually all interfaces used in 2114/2115/2116-series computers may be used with the 2100A Computer. No power supply extenders are necessary for any combination of interfaces installed. All I/O channels are buffered and bi-directional, and are serviced through a multilevel priority interrupt structure. The two optional [PHOTO] Figure 1.3. The HP 2155A Input/Output Extender adds 31 addi- tional I/O slots to the 2100. Full interrupt and addressing capabil- ities are included, plus sufficient power for any combination of interfaces. 1-5 direct memory access (DMA) channels are program-assignable to any two of the 14 interface slots in the mainframe, expandable to 45 slots if DMA is also installed in the extender, and can be dynam- ically reassigned. DMA transfers occur on a cycle-stealing basis, not subject to the I/O priority structure. The total bandwidth through both DMA channels is more than one million words per second. A unique channel identification and service priority interrupt is provided for every Input/Output channel used. Priority levels of the peripheral equipment connected to the computer can be altered simply by changing the positions of the interface cards in the I/O slots. Virtually every Hewlett-Packard measurement instrument provides a digital data output that can be interfaced to the 2100. a. Digital voltmeters and associated signal converters for measuring dc and ac voltages, currents, and resistances. With suit- able transducers, physical quantities such as pressures, loads, tem- peratures, and fluid flows can be measured with an HP computer. b. Electronic counters for frequency or period measure- ments from a few cycles per second into the microwave region. c. Scaler timers for nuclear radiation measurements. d. Digital test subsystems for measurement of integrated circuits, p.c. cards, components or assembled equipment. Analog input scanners are available for multiplexing signals into these measuring instruments. Digital scanners are also available for applications where it is desirable to multiplex the data outputs of these instruments before entry into the computer. Complete information on HP computer peripherals and measurement instru- mentation are available from your local HP field sales office. Off-the-shelf interface cards enable the customer to operate a wide variety of devices of his own choosing with the 2100. These in- clude 8- or 16-Bit Duplex Register cards, Microcircuit Interface card, a Relay Output card, a D-to-A Converter card, and Multi- plexed Input/Output for connection of up to 56 devices to the 2100. 1-6 1.2 INPUT/OUTPUT DEVICES Instructions or data may be entered on punched tape through a teleprinter, keyboard-display terminal, high-speed photoelectric tape reader or card reader. Data output devices include the tele- printer, which provides typewritten and punched tape records, tape punches, magnetic tape units (for IBM-compatible, 7- and 9-channel records) and line printers. Fixed-head disc or removable disc storage units are available for on-line mass storage requirements. Data can be entered on-line from Hewlett-Packard data sources and computed in real-time, or recorded on punched tape, magnetic tape, or disc for subsequent computer processing. Data-Set inter- faces are also available, which enable information to be transmitted over the telephone system, into or out of the HP computer. 1.3 SOFTWARE Software for the 2100 Computer includes four high-level pro- gramming languages: HP FORTRAN, HP FORTRAN IV, HP ALGOL, and HP BASIC, plus an efficient, extended assembler which is callable by FORTRAN and ALGOL. Utility software in- cludes a debugging routine, a symbolic editor, and a library of commonly used computational procedures such as Boolean, trigo- nometric, and plotting functions, real/integer conversions, natural log, square root, etc. Hewlett-Packard provides several systems built around BASIC in- terpreters. The single-terminal BASIC system allows the user to prepare and run BASIC language programs conversationally through a teleprinter. Programs can also be entered through a tape reader and punched out on tape punches. A memory of at least 8K words is required. A similar system, Educational BASIC, allows BASIC programs to be translated from marked cards. Several operating systems are available, covering a wide range of applications. The Basic Control System, which simplifies the con- trol of input/output operations, also provides relocatable loading and linking of user programs. The time-shared systems, using con- versational BASIC language, permit 16 or 32 terminals to be con- nected to the system, either directly or by telephone lines via Dataphones. The Hewlett-Packard Real-Time Executive (RTE) sys- tem permits several programs to run in real-time concurrently with 1-7 general-purpose background programs. This allows multiple data processing capabilities where separate computers are not econom- ically feasable. The user can write programs in HP Assembly, FORTRAN, or ALGOL languages. A Magnetic Tape System and a Disc Operating System are also available. These systems greatly increase the speed and simplicity of assembling, compiling, loading, and executing user programs. 1.4 SYSTEM EXPANSION FEATURES Memory sizes for the 2100A Computer are available in six con- figurations: 4K, 8K, 12K, 16K, 24K, and 32K. All core memory is accommodated in the computer main-frame and is field-installable. Figure 1.4 illustrates the configuration of the basic 2100A Com- puter and the expansion capabilities of memory and input/output. This figure approximately represents the top view and layout of the computer. For 4K or 8K memory, a card with appropriate stack configuration is installed in position A. For 12K or 16K [DIAGRAM] Figure 1.4. Internal Configuration 1-8 memory, the appropriate combination of 4K and 8K stacks is in- stalled in positions A and B. For 24K, positions A and B have 8K stacks and an 8K stack is added in position C. For 32K, a final 8K stack is added in position D. Expansion of input/output beyond the capability of the mainframe is accomplished by plugging an extender interface card into the highest address I/O slot (represented by E in figure 1.4), in place of an I/O interface card. This card is then cabled to an equivalent card in the 2155A I/O Extender Unit. The address formerly as- signed to slot E, and all higher addresses, are available in the extender. 1.5 FLOATING POINT HARDWARE The Floating Point Hardware option (12901A) supplies six addi- tional arithmetic instructions in the 2100's basic instruction set. These instructions provide a 5- to 20-fold increase in the perform- ance of floating point arithmetic functions. Firmware coding is stored in bipolar Read-Only-Memories (ROM's) contained in the microprocessor of the 2100. Floating Point Hardware may be used with the 2100 Basic Control System, Magnetic Tape System, Disc Operating System or Real- Time Executive System. It can be either field or factory installed and includes an Assembler, Cross Reference Symbol Table Genera- tor, Program Library, and a Diagnostic for the appropriate operat- ing system and memory size. 1.6 MICROPROGRAMMING THE 2100A Microprogramming allows the 2100's basic instruction set to be tailored to specific applications. Control storage in the 2100 con- sists of 1024 24-bit words organized into four modules. Micropro- grams for the basic 2100 instruction set are contained in the first 256 word module. A total of 768 words is available for extensions to the basic instruction set. (Firmware for the 12901A Floating Point option is stored in the first module and is reserved for this purpose.) 1-9 The Writable Control Store (WCS) option (12908A) provides the capability to microprogram the 2100 easily and conveniently. WCS consists of a single card which plugs into a computer I/O slot eliminating extensive cabling or additional power supply require- ments. The card contains 256 24-bit words of Random-Access- Memory, including all necessary address and read/write circuits. WCS can be programmed and verified under computer control using standard input/output instructions. WCS is read at full speed via a flat cable connecting it to the control section of the com- puter. Up to three WCS cards may be included for development and execution of user microcode. Software supplied with WCS included a micro-assembler, utility and I/O routines, drivers and diagnostics. The microassembler and utility routines require 8K of core (12K for use with a disc-operating system). Once devel- oped, microprograms will operate in any core size. The 12909A PROM Writer allows a user to convert microprograms developed with WCS to Read-Only-Memory, which can then be added to the control section of the computer. Programmable ROM's provide an economical way to reproduce debugged instruc- tion extensions once dynamic WCS is no longer required. The PROM Writer is located on a single card which fits in a com- puter I/O slot. This allows the PROM Writer to be implemented without extensive cabling or additional power supply. A stand- alone computer program, supplied with the PROM Writer, writes and verifies PROM chips using a punched tape. An 8K memory is required. 1.7 PHYSICAL SPECIFICATIONS 1.7.1 POWER REQUIREMENTS a. Line Voltage: 115 Vac (+-10%), single phase 12A or 230 Vac (+-10%), single phase 6A b. Line Frequency: 47.5 to 66 Hz c. Computer power consumption with internal supplied loaded to capacity by plug-in options: 800 watts 1-10 d. Power Cable: 10 feet, NEMA Type 5-15P (115 Vac operation) or NEMA Type 6-15P (230 Vac operation) 1.7.2 CURRENT AVAILABLE TO I/O 2100A 2155A Voltage Mainframe Mainframe +4.85 V 16.8 A 45.8 A - 2 V 7.0 A 19.5 A +12 V 3.0 A 5.0 A -12 V 3.0 A 5.0 A 1.7.3 ENVIRONMENTAL LIMITS a. Operating Temperature: 0 to 55 deg C (+32 to +131 deg F) b. Relative Humidity: 50 to 95% at 25 to 40 deg C (+77 to +104 deg F) 1.7.4 VENTILATION a. Intake: Rear Panel b. Exhaust: Sides of front panel and cabinet c. Air Flow: 400 cubic feet per minute d. Heat Dissipation: 2300 BTU/hour maximum 1.7.5 ALTITUDE a. Operating: 15,000 feet b. Non-operating: 25,000 feet 1.7.6 DIMENSIONS a. Width: 16 3/4 inches (42,5 cm) with adapters for mount- ing in 19 inch (48.3 cm) rack 1-11 b. Height: 12 1/4 inches (31,1 cm) (rack mounted) c. Depth: 2100A 26 inches (66 cm), 23 inches (58,4 cm) behind rack mounting ears 2155A 23 1/2 inches (59,6 cm), 23 inches (58,4 cm) behind rack mounting ears * Except as noted, specifications apply to both the 2100A and the 2155A I/O Extender. 1.7.7 CLEARANCE REQUIREMENTS a. Recommended Cable Clearance at Rear: 5 inches (127 mm) minimum b. Recommended Air Exhaust at Top: 3 inches (76,2 mm) minumum c. Recommended Air Exhaust at Sides: 2 inches (50,8 mm) minumum 1.7.8 WEIGHT a. Minimum: 92 pounds (41 Kg) b. Maximum: 115 pounds (52,2 Kg) with 32K and all I/O slots filled 1.7.9 SERVICE ACCESS a. Top panel slides back and up permitting top access to input/output connectors, test switches, plug-in circuit boards, and wiring. b. Bottom panel is removable for access to backplane wiring. 1-12 1.8 SYSTEM DOCUMENTATION Full hardware documentation is provided with each computer shipped to a customer and consists of five volumes as follows: a. 2100A Reference Manual. This manual describes the specifications, operating instructions and programming information for the computer. [This manual] b. Installation and Maintenance Manual. The I and MM contains instructions for installation, maintenance, troubleshooting and repair, except as covered in the power supply manual. c. Diagrams Manual. This manual provides interconnecting information and schematic diagrams for all assemblies of the computer except the power supply. d. IPB Manual. Replaceable parts ordering information, replaceable parts lists, exploded views, part locating diagrams, and numerical lists of parts for all assemblies of the computer except the power supply are covered in the IPB manual. e. Power Supply Manual. The power supply manual contains information necessary to troubleshoot and repair the power supply. This includes installation instructions, schematic diagrams, and replaceable parts information. Information on microprogramming the 2100 is contained in two publications. A 2100 Microprogramming Guide (5951-3028) serves as a complete reference on how to use the microprogramming capability of the 2100. Microassembler documentation is also required in order to format and assemble microprograms correctly. A software microprogramming guide (02100-90133) describes the various aspects of microprogramming software. All software supplied with HP computer systems is supported by complete user documentation. General types of software manuals include language manuals, operating system manuals, software operating procedures, user manuals, application manuals, and small program manuals. A "Software Installation Record" supplied 1-13 with each system lists all software furnished with the original equipment and provides an index to the software documentation. Software manuals typically sent with a 2100 computer system are listed below. (This pocket manual includes the first four of the listed reference manuals.) 1. HP Assembler 2. Basic Control System 3. HP FORTRAN 4. HP BASIC 5. ALGOL 6. Operating System Manual (Disc Operating System, Real- Time Executive System, or Magnetic Tape System, etc.) 7. Symbolic Editor 8. Relocatable Subroutines 9. System Operating Procedures In addition to the manuals shipped with each computer, a manual titled "Preface to Programming" (5951-1354) is also available. This manual is designed to provide a general introduction to the types of languages, operating systems, and user aids available for the 2100 computer line. 1-14