Questions tagged [microsoft-basic]
Microsoft’s Altair BASIC interpreter, its later ports, expansions and dialects (like PC BASIC, Commodore BASIC). Use [applesoft-basic] for the Applesoft dialect specifically.
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How to automatically set the random seed in Microsoft Z80 BASIC?
I am trying to find a way to automatically set the random seed in Microsoft Z80 Basic 4.7b on an RC 2014, as one would in Sinclair BASIC with RAND or RANDOMIZE.
I have got as far as understanding that ...
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Can you remove a variable in the 8-bit Microsoft BASICs?
For the 8-bit Microsoft derived BASIC interpreters (i.e. AppleSoft, Commodore, etc.) you define a variable by simply declaring it to have a value, e.g. A$ = "hello". When you no longer need ...
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Is there a full or partial disassembly of Microsoft basic for the Amiga or Mac?
It seems the Amiga and Mac versions of Microsoft Basic are very closely related. Down to at least the picture demo program that draws kinda concentric ellipses in a window.
I started disassembling ...
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What were the terms and costs for licensing Microsoft BASIC in the 1970s?
Many companies licensed Microsoft BASIC for their machines in the 1970s, most notably Commodore (in ROM in the PET 2001 from the start), Tandy/Radio Shack (Level II BASIC ROM some time not too long ...
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Where could I find details about the FAT8 file system? [duplicate]
I am investigating file systems and I put my eyes into FAT8. I have been able to get some information from the Microsoft BASIC-80 v5 manual, but that's not enough to build an image manipulation ...
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What is the use of the variable `B%` in DONKEY.BAS written by Bill Gates?
DONKEY.BAS, a video game written in 1981, was developed by Microsoft co-founder Bill Gates and early employee Neil Konzen.
We can experience the game here and view the source code of the game (only ...
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How much does Micro-80 BASIC resemble Microsoft BASIC?
The first DIY Soviet home computer Micro-80 and its successor Radio-86RK had an implementation of BASIC available (albeit not in ROM, but as an loadable binary). A page from which the link is taken ...
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How is the Commodore BASIC RND function seeded, depending on the argument?
In AppleSoft, RND with a negative number performs a seed on the generator with that number. So, as I understand it X=RND(-1) is the equivalent of RANDOMIZE 1:X=RND(1):
If aexpr is positive, returns a ...
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What does it mean to "publish machine code"?
The Wikipedia article on “An Open Letter to Hobbysts” says that Bill Gates complained about hobbyists pirating his software, and due to piracy he refused to publish the machine code of his Altair ...
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Do any FAT8 filesystem images survive?
According to Wikipedia, the original FAT8 filesystem was developed by Marc McDonald in 1977 or 1978, as part of "NCR BASIC +6", a port of Microsoft BASIC to an 8080-based NCR data entry ...
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Examples of floating-point numbers that don’t round-trip losslessly through text conversion in Microsoft BASIC
For a long time I thought it was kind of crazy that 8-bit Microsoft BASIC stores numeric constants in ASCII and has to parse them into its 32- or 40-bit floating point format at runtime. Why not parse ...
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Is NEC's PC-88VA compatible with N88-BASIC(86)
First, N88-BASIC runs on all PC-88.
It's a japanese Z80 computer, but PC-88VA are 16-bit, like the PC-98 and wonderswan. Instead, PC-98 runs N88-BASIC(86), which is different. I think only the PC-98DO ...
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Why was the 6502 version of Microsoft BASIC coded like the 8080 and 6800 versions even though this was rather inefficient?
It's quite clear that the 6502 version of Microsoft BASIC at all levels uses substantially the same structure and technique as the earlier 8080 and 6800 versions. As has been pointed out in various ...
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Why did the byte before TXTTAB have to be zero in MS-BASIC?
As mentioned in this answer about how the C64 stores BASIC program text, MS-BASIC uses a pointer called TXTTAB that points to the start of the program text, which is typically at address 1 in a page. ...
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Oddity in MS BASIC line lookup code on the 6502 [duplicate]
Does anyone know for sure why MS BASICs on the 6502 compared only the page number when deciding where to look for line numbers on branches? IIRC, it would only "start looking from here" if ...
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