SILICON GATE MOS 8702A

PROGRAMMING INSTRUCTIONS FOR THE 8702A

I.Operation of the 8702A in Program Mode

Initially, all 2048 bits of the ROM are in the "0" state (output low). Information is introduced by se\ectively program- ming "1 "s (output high) in the proper bit locations.

Word address selection is done by the same decoding circuitry used in the READ mode (see table on page 6 for logic levels). All 8 address bits must be in the binary complement state when pulsed VDD and VGG move to their nega- tive levels. The addresses must be held in their binary complement state for a minimum of 25 p'secafter VDD and VGG have moved to their negative levels. The addresses must then make the transition to their true state a minimum of 10 p'secbefore the program pulse

is applied. The addresses should be programmed in the sequenc~ 0 through 255 for a minimum of 32 times. The eight output terminals are used as data inputs to determine the information pattern in the eight bits of each word. A low data input level (- 48V) will pro- gram a "1" and a high data input level (ground) will leave a "0" (see table on page 6). All eight bits of one word are programmed simultaneously by setting the desired bit information patterns on the data input terminals.

During the programming, VGG , VDD and the Program Pulse are pulsed signals.

II.Programming of the 8702A Using Intel ® Microcomputers

Intel provides low cost program devel- opment systems which may be used to program its electrically programmable ROMs. Note that the programming specifications that apply to the 8702A are identical to those for Intel's1702A.

A.Intellec®

The Intellec series of program de- velopment systems, the Intellec 8/Mod 8 and Intellec 8/Mod 80, are used as program development tools for the 8008 and 8080 microproces- sors respectively. As such, they are equipped with a PROM programmer card and may be used to program Intel'selectrically programmable and ultraviolet erasable ROMs.

An ASR-33 teletype terminal is used as the input device. Through use of the InteHec software system monitor, programs to be loaded into PROM may be typed in directly or loaded through the paper tape reader. The system monitor allows the program to be reviewed or altered at will prior to actually programming the PROM. For more complete informa- tion on these program development systems, refer to the Intel Micro- computer Catalog or the Intellec Specifications.

B.Users of the SIM8 microcomputer programming systems may also program the 8702A using the MP7-03 programmer card and the appropriate control ROMs:

SIM8 system-Control ROMs A0860, A0861 and A0863.

III. 8702A Erasing Procedure

The 8702A may be erased by expo- sure to high intensity short-wave ultra- violet light at a wavelength of 2537A. The recommended integrated dose (Le., UV intensity x exposure time) is

6W-sec/cm2•Examples of ultraviolet sources which can erase the 8702A in 10 to 20 minutes are the Model UVS-54 and Model S-52 short-wave ultraviolet lamps manufactured by Ultra-Violet Products, Inc. (5114 Walnut Grove Avenue, San Gabriel, California). The lamps should be used without short-wave filters, and the 8702A to be erased should be placed about one inch away from the lamp tubes.

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Intel 8080 manual Programming Instructions for the 8702A, Operation of the 8702A in Program Mode, III a Erasing Procedure
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8080 specifications

The Intel 8085 and 8080 microprocessors were groundbreaking innovations in the world of computing, paving the way for future microprocessor development and personal computing.

The Intel 8080, introduced in 1974, was an 8-bit microprocessor that played a fundamental role in the early days of personal computing. With a 16-bit address bus, it had the capability to address 64 KB of memory. Running at clock speeds of 2 MHz, the 8080 was notable for its instruction set, which included 78 instructions and 246 opcodes. It supported a range of addressing modes including direct, indirect, and register addressing. The 8080 was compatible with a variety of peripherals and played a crucial role in the development of many early computers.

The microprocessor's architecture was based on a simple and efficient design, making it accessible for hobbyists and engineers alike. It included an 8-bit accumulator, which allowed for data manipulation and storage during processing. Additionally, the 8080 featured registers like the program counter and stack pointer, which facilitated program flow control and data management. Its ability to handle interrupts also made it suitable for multitasking applications.

The Intel 8085, introduced in 1976, was an enhancement of the 8080 microprocessor. It maintained a similar architecture but included several key improvements. Notably, the 8085 had a built-in clock oscillator, simplifying system design by eliminating the need for external clock circuitry. It also featured a 5-bit control signal for status line management, which allowed for more flexible interfacing with peripheral devices. The 8085 was capable of running at speeds of up to 3 MHz and had an extended instruction set with 74 instructions.

One of the standout features of the 8085 was its support for 5 extra instructions for stack manipulation and I/O operations, which optimized the programming process. Additionally, it supported serial communication, making it suitable for interfacing with external devices. Its 16-bit address bus retained the 64 KB memory addressing capability of its predecessor.

Both the 8080 and 8085 microprocessors laid the groundwork for more advanced microprocessors in the years that followed. They demonstrated the potential of integrated circuits in computing and influenced the design and architecture of subsequent Intel microprocessors. Their legacy endures in the way they revolutionized computing, making technology accessible to a broader audience, and their influence is still felt in the design and architecture of modern microprocessors today.
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