The Z80 took over from the 8080 and its offspring, the 8085, in the processor market, and became one of the most popular 8-bit CPUs.

Although the 8085 is an 8-bit processor, it also has some 16-bit operations.

It could also accept a second 8085 processor, allowing a limited form of multi-processor operation where both processors ran simultaneously and independently.

The CMOS version 80C85 of the NMOS / HMOS 8085 processor has several manufacturers.

In many engineering schools the 8085 processor is used in introductory microprocessor courses.

* GNUSim8085 – An open source simulator software for the 8085 processor.

The processor was an 8-bit Intel 8085, with bank switching logic to manage 256 kB of memory.

* ISIS ( operating system ), used on the Intel 8085 processor

The same basic idea was employed for the Intel 8086, although, to allow for more radical extensions, binary-compatibility with the 8080 was not attempted here ; instead the 8086 was designed as a more regular and fully 16-bit processor that was source-compatible with the 8008, 8080, and 8085.

The 8080 device, often described as the first truly useful microprocessor, was eventually replaced by the depletion-load based 8085 ( 1977 ) which could cope with a single 5V power supply instead of the three different operating voltages of earlier chips.

Marketed as source compatible, the 8086 was designed to allow assembly language for the 8008, 8080, or 8085 to be automatically converted into equivalent ( sub-optimal ) 8086 source code, with little or no hand-editing.

However, the 8086 design was expanded to support full 16-bit processing, instead of the fairly basic 16-bit capabilities of the 8080 / 8085.

Another factor was that the 8088 allowed the computer to be based on a modified 8085 design, as it could easily interface with most nMOS chips with 8-bit databuses, i. e. existing and mature, and therefore economical, components.

The most important of the early OSes on these machines was Digital Research's CP / M-80 for the 8080 / 8085 / Z-80 CPUs.

Though the concept was first proposed in 1991, software-defined radios have their origins in the defense sector since the late 1970s in both the U. S. and Europe ( for example, Walter Tuttlebee described a VLF radio that used an ADC and an 8085 microprocessor ).

A downside compared to similar contemporary designs ( such as the Z80 ) was the fact that the buses required demultiplexing ; however, address latches in the Intel 8155, 8355, and 8755 memory chips allowed a direct interface, so an 8085 along with these chips was almost a complete system.

An improvement over the 8080 was that the 8085 can itself drive a piezoelectric crystal directly connected to it, and a built in clock generator generates the internal high amplitude two-phase clock signals at half the crystal frequency ( a 6. 14 MHz crystal would yield a 3. 07 MHz clock, for instance ).

Later 8085 and 8086 support was added including ICE ( in-circuit emulators ).

The 8085 CPU was only one part of a much larger family of chips developed by Intel, for building a complete system.

* MCS-85 was a family of Intel processors including the 8085

The IMSAI 8080 was an early microcomputer released in late 1975, based on the Intel 8080 and later 8085 and S-100 bus.

The 8-bit Intel 8080 ( as well as the 8085 and 8051 ) microprocessor was basically a slightly extended accumulator-based design and therefore not orthogonal.

This was based on two Intel 8085 series microprocessors: one of which was given over to I / O control.

Similar I / O-port schemes were used in the backward compatible Zilog Z80 and Intel 8085 as well as the closely related x86 families of microprocessors.

Both processors were sometimes used in computers running the CP / M operating system, and the 8085 also saw use as a microcontroller, by virtue of its low component count.

In addition to an 8080 / 8085 assembler, Intel produced a number of compilers including PL / M-80 and Pascal languages, and a set of tools for linking and statically locating programs to enable them to be burnt into EPROMs and used in embedded systems.

The Swiss company SAIA used the 8085 and the 8085-2 as the CPUs of their PCA1 line of programmable logic controllers during the 1980s.

* TRS-80 Model 100 used the CMOS version of the 8085 in a laptop computer

* IBM System / 23 Datamaster gave IBM designers familiarity with the 8085 support chips used in the IBM PC

Only a few minor instructions were new to the 8085 above the 8080 set.

The rad-hard version of the 8085 has been in on-board instrument data processors for several NASA and ESA space physics missions in the 1990s and early 2000s, including CRRES, Polar, FAST, Cluster, HESSI, the Sojourner Mars Rover, and THEMIS.

Both the architecture and the physical chip were therefore developed rather quickly by a small group of people, and using the same basic microarchitecture elements and physical implementation techniques as employed for the slightly older 8085 ( and for which the 8086 also would function as a continuation ).

This included ICs originally intended for support and peripheral functions around the 8085 and similar processors ( not exclusively Intels ) which were already well known by many engineers, further reducing cost.

Like the 8080, the 8085 can accommodate slower memories through externally generated wait states ( pin 35, READY ), and has provisions for Direct Memory Access ( DMA ) using HOLD and HLDA signals ( pins 39 and 38 ).

Intel produced a series of development systems for the 8080 and 8085, known as the MDS-80 Microprocessor System.

PL / M compilers have been made for the following processors / controllers: Intel 4004, 8008, 8080, 8085, 8051, 8052, 8096, 80196, 8086 / 8088, 80186 / 80188, 286, and 386.

Although the file format is the same in MS-DOS and CP / M,. COM files for the two operating systems are not compatible ; MS-DOS COM files contain x86 instructions and possibly MS-DOS system calls, while CP / M COM files contain 8080 instructions ( programs restricted to certain machines could also contain additional instructions for 8085 or Z80 ) and CP / M system calls.

The Intel 8259 is a Programmable Interrupt Controller ( PIC ) designed for the Intel 8085 and Intel 8086 microprocessors.

The 8085 has extensions to support new interrupts, with three maskable interrupts ( RST 7. 5, RST 6. 5 and RST 5. 5 ), one non-maskable interrupt ( TRAP ), and one externally serviced interrupt ( INTR ).

Heath / Zenith then designed a dual Intel 8085 / 8088 based system dubbed the H100 ( or Z-100, in preassembled form, sold by ZDS ).

The interrupt cycle of the 8080 / 8085 will issue three bytes on the data bus ( corresponding to a CALL instruction in the 8080 / 8085 instruction set ).