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The DEC PDP-8, a 12-bit machine with 4k words of memory, had 8-bit direct addressing (7-bit offset and a 1-bit Page Zero selector). However, an Indirect bit in the order code caused the contents of the directly addressed location to be used as a 12-bit address of the real operand. Later models of the PDP-8 family could have up to 7 more "Fields" ...


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The RCA 1802 CPU had only 8 address lines, which were time multiplexed to specify a 16 bit address. It was used in "telly tennis" type game machines in the mid 1970's and early home computers like the COSMAC ELF as well as the Hubble space telescope. Just recently my retired neighbour was regaling me with stories of when he was developing a system ...


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Not quite there, but close, is the VT52 text terminal with a CPU that has a 10-bit code address space. The data address space is 11 bits. As answered by others, low end microcontrollers may well have 8-bit code and/or address spaces.


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PIC: 7 bit address space The Microchip PIC family of CPUs specifically the 10, 12 and 16 series have 7 bits of address space. While 7 bits is not exactly 8 bits this shows that there are commercial CPUs still on sale and still widely used that have less than 8 bit address space (they are used for example for power management on some Macs and are the most ...


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The Intel 8048 which was used in the Magnavox Odyssey2 had an 8-bit external address bus.


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The KENBAK-1 has 256 bytes of memory. I'm not certain whether it had an 8-bit PC. https://en.wikipedia.org/wiki/Kenbak-1


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The first that comes to mind is Cypress' M8C core used in the PSOC-1 series. While it has a 16 bit program address space (and thus 16 bit jump instructions), its data as well as the register space are each strictly 8 bit. Implementations do use up to two sets of 256 registers and may offer several sets of 256 Byte banks. From the manual: The M8C is an 8-bit ...


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Not strictly an answer, but some early computers had very limited addressing. The Harwell Dekatron computer, which operates entirely in decimal, has an address space of 100 words, of which 90 are RAM and the other 10 are devices. Programs for it are usually run directly from a paper tape device (where the tape, rather than the PC register, is advanced after ...


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According to wiki IBM System 360 had byte addressable RAM. Yes. [Considering this and the title "Why did IBM System 360 have byte addressable RAM" it feels as there's a mixup about what addressing and RAM means. See some thoughts about that at the end)] Previously IBM had machine with word addressable memory. No. Only very few. IBM did make all ...


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Programmers do need to process characters from memory, and characters are generally smaller than the machine word. The architectural possibilities seem to be: Instructions that only read/write words. Programmer must use explicit shift, mask, logical-or to operate on characters. There are special instructions that use a "character address" that ...


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The 360 was designed as an all-purpose system. That means that among other things, it should be suitable for processing text. Nowadays, a computer for processing text could perfectly well go with 32 bit addressing unit and take the attitude that you always use Unicode, but in those days Unicode didn't exist and it would've been too expensive to use 32 bits ...


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4MiB was the maximum that could be installed in the 1040STE. The MMU didn't allow for more.


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What is the total size of 1040STE with 4 of these SIMMs installed? Should be 4 MiB. The chips shown are MiBit chips (1 Mi x 1). 8 of them give a Mibyte per SIMM. It also fits, as 4 MiB is the default (i.e. without additional tricks) maximum RAM for a 1040ST. This great page tells about everything you never wanted to know about Atari ST using SIMM. How to ...


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I think the first question to answer is whether booting from a game floppy image via the Gotek is the best way to achieve game compatibility with an expanded Amiga. In my experience, compatibility is better when using WHDLoad images instead of unmodified floppy images for expanded Amigas. You mentioned you have a 4GB IDE-CF HDD. If you already have WHDLoad ...


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This is kind of an extension to a [previous question] TL;DR: The 7030 addressing, works for many instructions, on bit level, not words. Next to all data structures, including bytes, could be located at any bit address. All addressing was always done using 24 bit. Byte is not a hard defined entity like today, but simply a name for a repeated bit-group (i.e. 1 ...


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As per @Raffzahn's comment on his answer to Why did IBM 7030 or IBM 360 use byte and word addressing simultaneously, the 8 is an artefact of multi-byte instructions, where there was only 3 bits to specify the skip, making it trivial to have 1-8 bits. @NoNameQA I added more to the answer. No, 8 was simply what could be put in a 3 bit field offered by ...


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[Please see as well this answer, as it's kind of an extension] Why did IBM 7030 or IBM 360 use byte and word addressing simultaneously Not sure what's with /360 reference here, as it's uses byte addressing (*1). The 7030 in contrast used word and bit addressing. Word addressing of 18 bit when it was about words, and bit addressing in the form of a 24 bit ...


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'Byte' was used before it meant '8 bits' and It was used on machines that had word-addressable memory. The point was for the program to be able to read and write data of less than a word size. The PDP-10, with which I am familiar, had "load byte" and "deposit byte" instructions which could read any part of a word, sized from 0 to 36 bits....


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The year you've picked has a strong influence on the answer. By 1999, most new games were being released to run under 32-bit Windows using DirectX, and were therefore running in a demand-paged multitasking virtual memory system. This has two consequences: Checking available memory was no longer necessary - if you didn't have enough, the OS would emulate it ...


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