# reading matter | IMSAI 8080. Computer craftsmen

Today, we will mentally return to the days when personal computers were born. They have not yet developed a serious attitude. What can I say, there was a steady opinion that mainframes (“mainframes”) are forever, and “personal computers” will have to remain funny toys that have no place in serious calculations. Oh, how the supporters of this point of view were mistaken! Then they would see a smartphone, the power of many times superior to computers of that era. But back to the story of our current historical narrative. At the end of the summer, in August of the distant 1975, the computer IMSAI 8080 appeared.

For all the time it was released only 20 thousand of these machines. In the assembled state, it cost 931 US dollars, and in the form of a set of spare parts, of which the craftsmen were given to independently assemble a computer, its price was significantly lower, only 599 US dollars.

It was served by an Intel 8080A processor with a “grand” clock frequency of 2 megahertz. It was two, and precisely megahertz, and some gigahertz people then could only be imagined by science-fiction writers, but even they very rarely turned to this topic, paying more attention to space and humankind's conquest of the Universe.

The maximum possible IMSAI 8080 RAM reached 64 kilobytes. But! A real miracle for those times. On the front of the computer flaunted the LCD screen. Management was carried out using all located on the same front panel switches. Before the birth of the first laptop with a full keyboard, there were still nine years left. The IMSAI 8080 used the BASIC programming language interpreter as the operating system, which is typical for computers of that time. However, the CP / M operating system created by Gary Kildall two years earlier, that is, in 1973, was also supported.

The data carriers could be either tape cassettes or a drive for magnetic floppy disks, the so-called floppy disk drive. I must say that this information storage technology turned out to be one of the most persistent. A few years ago, floppy disks were actively used and only recently gave way to flash drives.

Created by IMS Associates, located in the California city of San Leandro, IMSAI 8080 is notable for being one of the first consumer-class personal computers in the history of our civilization.

Some clarification should be made here. IMSAI 8080 was not the first computer of this kind. But the majority of its predecessors were supplied as a kit for self-assembly, while IMSAI 8080 could be bought (albeit significantly overpaying) already fully prepared, so to speak, for consumption. Of course, even then (as indeed now), people who can assemble a complex electronic device with their own hands did not make up the majority of consumers. However, amateurs could save several hundred dollars and purchase IMSAI 8080 in the form traditional for its time, that is, in the form of a kind of “designer”.

In this case, they would have to spend several days assembling and testing. But after all, many of these classes are fun. I must say that in those days, many people were fond of electronics. Now interest in this exciting lesson has declined slightly. The fact is that today there is a huge variety of electronic devices on the market, which are already sold in finished form and many of them even at quite reasonable prices. In the mid-seventies, things were different, and the skills of the master of all trades were valued and were the reason for increasing self-esteem.

Experts in the history of technology IMSAI consider the most beautiful of the first microcomputers. It is difficult to argue or agree. Aesthetic preferences have been and remain a matter of taste.

In the basic configuration, IMSAI 8080 had only a central processor. The programmer could enter commands using switches located on the front panel, and see the results on the LCD display located on the same panel. Neither the keyboard nor the extra display was required at all.

But programming in this way was too slow and tedious. Any mistake made led to the fact that all program input had to be restarted, it was simply nowhere to correct. Only true connoisseurs of uneasy ways, romantics of programming, could fully enjoy such a laborious, but fascinating (in their opinion) process.

Like all early S-100 based systems, the IMSAI 8080 was just a large metal case with a power cord and numerous expansion card slots. But the ancient S-100 system bus had excellent quality. She did not impose restrictions on the number of connected peripherals. Therefore, there were no problems in order to connect a full-fledged keyboard, a normal (according to the time notions about the norm) monitor and data collector, as well as other types of additional devices. Thus, the user has at his disposal a full-fledged personal computer.

Some considered IMSAI to be the first in the history of a clone of other computer systems and called MITS Altair 8800 as its prototype, a similar computer that appeared a few months earlier. IMSAI even supported the same cards as Altair. The reason for this was the common S-100 system bus for both cars. Experts in the field of information technology noted that IMSAI was not the only computer whose system diagram was similar to the MITS S-100, but it was the first, most likely the first, unless historians have other data.

Unfortunately, IMSAI 8080 was difficult to program in such a way that it responded to the tasks that the broad masses of users place on computers. Very little software was created for him. Note that even now a large selection of applications is considered perhaps the main advantage of a particular platform.

A year passed, another one followed him, and more friendly computers appeared to the average user, and IMS Associates went bankrupt in 1979.

All this was at the dawn of the era of personal computers. I must say that in September 1975, BYTE magazine wrote:

Computers: the greatest toys in the world!

Since then, not many years have passed, but now no one doubts that computers are not toys. Rather, not only toys. They help a person in work, they entertain him and provide information, make it possible to communicate. All this magnificence would be unthinkable without the first steps that were taken in the mid-seventies of the past, twentieth, century, which will forever go down in human history as a century glorified by numerous technical inventions and discoveries.

The chronicle of scientific and technological progress is written today, like yesterday, and we pay the main attention to new products. And this is true: it is human nature to show interest above all for today's day. But sometimes it is very important to look back, if only then, to understand what a gigantic way the industry has done in just over three decades and a little.

Source: Oldcomputers.net

The article is based on materials https://hi-news.ru/computers/chtivo-imsai-8080-kompyuter-narodnyx-umelcev.html.