56

There are many issues here. As it is already said in comments, decoupling capacitor is a must! 555 (non-CMOS) timer output is very much like the output of TTL ICs, however Z80 requires a firm logic one. When feeding Z80 clock pin from a TTL output, you should use pullup resistor of 200..500 Ohm. NMOS Z80 uses dynamic logic, that means it has some minimal ...


46

People nowadays think of BASIC as something lesser and generally tied to puny microcomputers, but BASIC was the language of choice for many scientific, engineering and business computers in the 1970s. It had a strong foothold with mini computers, years before the microprocessors made its debut on the desktop. Think HP (Instrument) BASIC for all their ...


26

One example of popular 8-bit computers without BASIC in ROM is the first three Atari 8-bit computers, the 400, 800, and 1200XL, which didn’t have BASIC built-in but on a separate cartridge. Their predecessor, the Atari Video Computer System, also had a BASIC Programming cartridge, written by Warren Robinett, but it wasn’t supplied with the system (it was ...


24

Were there any 8-bit CPUs with 24-bit addressing? Not many. Most prominent and best fitting examples would be WDC 65816 of 1983 Hitachi 64180 of 1985 / Zilog Z180 of 1985 (only 19/20 bit) eZ80 of 1998 Then there 8/16/32 bit hybrids - able to run 8 bit code and available with external 8 bit data bus, but as well with 16/32 bit code (extensions): Zilog ...


21

Short Answer: Motorola used it for their 6800 and MOS (6500) inherited it from Motorola. After all, the 6500 team members came out of the 6800 project so they were already used to it. Long Answer: If the 0x prefix clearly predates the 8-bit revolution, It doesn't, really. Motorola used the $ prefix already with the 6800 of 1974. Unix had only recently (...


20

(Please see as well other fine answers for more computers fitting the list) I guess we can put them in four categories (in descending order of application): Machines with Different Language in ROM The early models of the Soviet BK-0010 series had FOCAL in ROM. BASIC was available as an add-on module. Later models starting from BK-0010.01 already had BASIC in ...


17

Does anyone know of any bitmap-based 8080/8085 (or, failing that, Z80) computers? The Kyotronics 85, TRS-80 Model 100, NEC PC8201 and Olivetti M-10 were 8085 based notebook-style computers all based on the KR-85 platform, which had a 640 x 64 pixel graphic LCD screen. It was introduced in 1983. Here's an example of bitmap graphics on the PC-8201, a 3D maze ...


16

This was more of a marketing question than a technical one. The historical fact is that most vendors of 8-bit personal computers chose to include BASIC. The simple answer as to why they made this choice is pretty obvious - It was the standard. So, slightly restating the question posed, one could ask "Why was BASIC the standard?" It was a standard in the ...


16

If we're not talking about BASIC as a programming language, but the operational commands that surround it, then the answer is that they surely reimplemented the command structure of existing timesharing systems that offered BASIC, in particular the 1964 Dartmouth Time Sharing System (the progenitor of BASIC). There are nits to pick, however. The "command ...


15

The French company Micronique had a few models that came with Forth instead of BASIC, like the Hector HRX and Hector MX. https://www.old-computers.com/museum/computer.asp?c=142&st=1


14

I'd just like to expand on a couple of points in lvd's excellent answer. Reset Circuit You might get by with just using a jumper wire to short the reset pin to ground for a brief moment after you've powered up the CPU. It's worked for me, but if you're having problems it's best to build a proper reset circuit. Many CPUs have a minimum length for the reset ...


11

Yes. AVR microcontrollers with more than 64KB of memory do have 24-bit addressing. They have some additional registers for that purpose RAMPX, RAMPY, RAMPZ, RAMPD and EIND: 8-bit segment registers that are prepended to 16-bit addresses in order to form 24-bit addresses; only available in parts with large address spaces. https://en.wikipedia.org/...


10

To start with, there was a whole lot of 8080 based home computers, many of them offering bitmap graphics, but more important, already the very first general available colour video board, the Dazzler offered bitmap graphics. The Dazzler was most definite meant for use with an 8080, as it was available at a time before the Z80 could be bought. For the ...


9

I started programming microcomputers in 1979 as an 11-year-old in Melbourne, Australia. This is how it is in my memory, which I am sure is only a rough approximation of reality. I never saw anything like an Altair or Apple I in the very early days. I did see a couple of kit computers with hex keypads. I never saw a ZX 80 but there were a small number of ZX ...


9

There is eZ80, a Z80 compatible successor, generally considered an 8-bit CPU, and it features 24 bit address space (though not in the Z80 compatible mode).


9

You didn't mention the MPF-II's release: That was, apparently, 1982. There were earlier Japanese Microcomputers than that, notably the NEC PC-8000 series (released in 1979) that used a Katakana/Kanji character set (that had to be removed/changed when preparing a release for the US market in 1981) Even the Hitachi Basic Master (released 1978 and commonly ...


7

Motorola 68008, a cheaper 68000 variant. Not exactly as you described it, 20-bit and later 22 bit address bus I think and a 8-bit data bus.


7

There is no way to establish a classification of 'efficiency' (whatever 'viability' is supposed to be) with the information given. The characterisations given, like Number of Registers, Number of flags Memory addressing range Number of instructions etc. bear no hint about performance at all. More or less registers, flags or instructions are not per se ...


7

The definition of an OS is quite fuzzy, though it generally includes resource allocation and handling, a way to indicate actions to be performed ('commands', not necessarily interactive), and a way to run user programs. Your BASIC-only microprocessor systems seem to fulfil that definition, though the "OS" aspects were pretty limited. We can at ...


7

Some more Soviet home computers that lacked BASIC in their ROMs: Vector-06C Apogey BK-01 (wiki is only available in Russian and it is not very clear about whether there were built-in BASIC, but other sources say there weren't) Radio-86RK Specialist Orion-128 Microsha (only Russian, clear statement that the BASIC was loadable from the tape)


7

I had a Colecovision Adam computer back in the day. A very odd feature of that system was that the power supply was actually in the printer. It came with a word processor in its ROM rather than a programming language. I remember using all my lawn mowing money to buy SmartBASIC and SmartLOGO on cassette tape along with a 300-baud modem for it.


6

BASIC was cheap on resources. Cheap on ROM, cheap on RAM, functional and productive. Nothing else came close -- not even Forth (which really required a disk drive to be truly usable, though there were exceptions). In the microcomputer BASICs, program code and the source code were the same. The original text is consumed and parsed in to the internal token ...


6

I'm not sure that the IBM5100 could really be considered a "home computer", and I believe that it was not an 8-bit computer (it was, as I recall, based on a cut-down version of the 360), but it might pass today's "sniff test" for home computers, and came in two versions: The 5100B did in fact have BASIC in ROM (which IBM called ROS), but ...


6

The Nascom 1 didn't have any high level languages. Its successor the Nascom 2 came with BASIC however. The Nascom 1 and 2 were single-board computer kits issued in the United Kingdom in 1977 and 1979, respectively, based on the Zilog Z80 and including a keyboard and video interface, a serial port that could be used to store data on a tape cassette using the ...


5

So could BASIC interpreters on such systems be considered an operating system? Well, the resident (*1) software initializes the machine and all I/O, prepares operation, offer services for I/O (disk, tape, ports, clock, etc.) and dumps the user at a command shell. So what would you call that. For all practical purpose BASIC can be seen as the shell of that ...


5

I see 3 main reasons: The 8-bit computers were targetting amateur computer enthusiasts, and a lot of beginner children. BASIC were specific to each machine to allow easy access to keyboard, sound and graphics, with simple syntax, global variables, not too many concepts like functions, scopes, etc. to avoid losing the users. Imagine having to count the ...


5

This feels like it'll end up being a list answer, so this is a community wiki answer. Please edit! 8-bit home computers that did not come with a welcome cassette include: The ZX80 and ZX81 See the ZX80's user manual and the ZX81's; for the ZX80: A twin cable with 3.5 mm jack plugs at both ends is provided to connect the ZX-80 to a cassette recorder. Don't ...


5

Likely too many to list. However, PMD-85 is notable and borderline because it included a BASIC on a detachable ROM module. By default, it started into a monitor (with tape loading routines etc.); there were other ROM modules produced (with Pascal, LOGO, IIRC also KAREL). But they were almost exclusively used with the BASIC module.


5

The ELAN Enterprise didn't have BASIC built-in. Its IS BASIC was supplied on a cartridge (that was, admittedly, part of the base pack). But you could just as well use any other language. It's "main application" was WP - A simple editor/word processor. If you consider the Cambridge Z88 a home computer, its "main OS" was definitely not (BBC)...


4

I had a Cosmac VIP - a bare board edition - it didn't even come with the case† shown in the first picture on the linked website. The on-board ROM provided only the very lowest-level of boot-up/code entry/tape reading but a "better" (and I use that in a very loose sense) interpreted language, "Chip-8", was available but was only provided in printed ...


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