Posts by drj@typo.social
(DIR) Post #AbNMh93IeA0q0wPxLc by drj@typo.social
2023-11-01T10:47:47Z
0 likes, 2 repeats
Welcome to #MOVember, one asm MOV instruction each day.The Motorola MC68000 has a BEAST of a MOV instruction.Official assembler mnemonic: MOVE. Refreshingly clear!You could move to and from registers and/or memory. 8-, 16-, 32- data sizes. Post increment, predecrement. Including memory-to-memory moves (*Ferris Bueller soundtrack voice*: Oh Yeah).`*d++ = *s++` is a single instruction in 68000.Officially destination on the right: MOVE A7,D0 copies the A7 register to D0Please 🔁#68k
(DIR) Post #AbOOlaLVVPNYtA8fzM by drj@typo.social
2023-11-02T10:00:24Z
0 likes, 0 repeats
@smallsees um, LDA is $3E = 62. On Zilog Z80 :)
(DIR) Post #AdEQZYAt7NenIuuV7I by drj@typo.social
2023-12-26T13:57:32Z
1 likes, 1 repeats
Look at this super cute fox i found. Made of electronic components: resistors on around the nose, chips on the legs. In the February 1976 edition of Modern Data. Preserved by archive.org.#Fox
(DIR) Post #AiLwuvZkklqoNrUfM8 by drj@typo.social
2024-05-28T14:03:16Z
3 likes, 3 repeats
My most recent @FontsInUse post is a couple of notes about the cover of a 6809 assembler manual.#mc6809https://fontsinuse.com/uses/56920/6809-mnemonic-assembler-manual
(DIR) Post #Akf5vVp7p6eZCwPRMe by drj@typo.social
2024-07-31T08:24:34Z
1 likes, 0 repeats
"If you lose or damage your friend there is no recovery plan"#friend
(DIR) Post #AtP5dAXNkw1iCmfphI by drj@typo.social
2025-04-19T07:33:35Z
0 likes, 0 repeats
@catsalad *Windows NT 3.5.1 sad face*
(DIR) Post #AtzLYeymG2piLa6nU8 by drj@typo.social
2025-05-11T15:27:01Z
0 likes, 0 repeats
@futurebird in the Arts we would get preschoolers to make paints (umbre, ochre, and other shades of brown) from mud. The older kids would use ants to sort the soils into fineness.
(DIR) Post #Aw9LAxaOLxQ9O51Csq by drj@typo.social
2025-07-07T10:27:14Z
0 likes, 0 repeats
There are surprisingly few fonts based on, or used by, actual typewriters. In the interests of finding out the right answers by posting wrong ones:Prestige Elite, Typewriter Elite (balls and fillets), Courier (no balls, slab serifs), LTC Remington Typewriter (wavy seven). A2 Typewriter, 1403 Vintage Mono, and Orator feature in the next post.Please boost (to increase the rage replies).(samples from identifont)1/#TypewriterFont #font #Typewriter #Monospace
(DIR) Post #Ay26R4bgx57iVReOZM by drj@typo.social
2025-09-09T11:21:08Z
0 likes, 0 repeats
Re-reading the ZX81 manual, spotted a reference to POP-2, a programming language i had somehow not heard of. Wikipedia https://en.wikipedia.org/wiki/POP-2:the function callf(x, y, z);can be written asx, y, z; f();(commas and semicolons being largely interchangeable) or evenx, y, z.f;or(x, y, z).f;(Because of the stack-based paradigm)@typeswitch and @neauoire might want a quick look if they haven't come across it.
(DIR) Post #Az7js3G3wI3RafBVZI by drj@typo.social
2025-09-17T17:38:52Z
0 likes, 0 repeats
So if anyone wants to participate in a crowd-sourced effort to discover the pixel ratio of the ZX Spectrum, they could type this program into their Speccy and take a photo of the screen as square-on as you can get it; that would be great. Sample from emulator on right.#Retrocomputing #ZXSpeccy
(DIR) Post #Az7jsBoO8YGW7RJ2BM by drj@typo.social
2025-09-17T20:07:10Z
0 likes, 0 repeats
Here's mine. Holding the camera free on the left; on the right using my OrthoScope TM (a cardboard box with a small hole in it).
(DIR) Post #Az7jsK0NfqbzWwyizA by drj@typo.social
2025-09-17T20:28:02Z
0 likes, 0 repeats
So my calculation on the full checkerboard 2590/1689/(256/176) which is… 1.054. I also measured using a tape measure (quite hard as the true screen is many mm behind the front sheet of plastic): 522mm/335mm/(256/176) = 1.07.I also measured the "4:3" area on my TV: 688mm:513mm which is 4:3 * 1.0058 (so, correct up to my ability to measure it at this moment in time).Conclusion: Panasonic Viera displays 4:3 area correctly. Observed ZX Spectrum pixel aspect ratio very close to theoretical 1.055
(DIR) Post #Az7jsScbdbwSFovMg4 by drj@typo.social
2025-09-17T21:09:38Z
0 likes, 0 repeats
Using this observed ZX Spectrum pixel aspect ratio of 1.054 and knowledge that the pixel clock is 14 MHz to estimate the pixel clock of a true square pixel, gives a true square pixel clock estimate of 14.76MHz; absurdly close to the industry standard 14.75MHz and the true value of 14.77MHz. Haha.#Pixels
(DIR) Post #Az7jsSfRT4D6OcFd68 by drj@typo.social
2025-09-17T20:40:39Z
0 likes, 0 repeats
My theory for pixel aspect ratio is that there are 576 lines on a 4:3 display so horizontally there are 768 square pixels. Active image timing for PAL is 52µS (or maybe 51.95, who can say). So the ZX Spectrum with a 14MHz pixel clock has an aspect ratio of 768:52×14 which is 1.055 (minus rounding).
(DIR) Post #AzQTAaNRXFFYIo7xh2 by drj@typo.social
2025-10-21T06:50:11Z
0 likes, 0 repeats
@discatte purple game boy. Purple GameCube. Purple GameCube controller. Purple GameCube keyboard for playing Phantasy Star Online (I don't _think_ I made that up)
(DIR) Post #AzRHdigYifVkAz9dGy by drj@typo.social
2025-10-21T16:15:34Z
0 likes, 0 repeats
@discatte Does the Barbie typewriter count?from https://www.cryptomuseum.com/crypto/mehano/barbie/(omg, only just noticed the trademark "B" key)
(DIR) Post #AzRNPdiyxzxASdxPQu by drj@typo.social
2025-10-21T17:20:25Z
0 likes, 0 repeats
@discatte think it might be Handel Gothic, which is quite sci-fi. It's on the Close Encounters poster for example.
(DIR) Post #AzRWNFWIt2D6OsxhFg by drj@typo.social
2025-10-21T19:00:50Z
0 likes, 0 repeats
@discatte oh yeah the DS9 credits (which I haven't seen) are apparently done in Handel Gothic. Or something very similar.
(DIR) Post #B0GaXQpCG5URnntbEG by drj@typo.social
2025-11-15T10:12:16Z
0 likes, 1 repeats
Instead of internet search,i've been trying to use more the documentation that is installed on my computer. For Python RE syntax, i'll go "import re; help(re)" (Python's RE module has pretty good help). Instead of random internet searches for awk or sed syntax, i'll use `man awk` or `man sed` (or my copy of AWK Programming Language if i'm in the home office). Even git has man pages, but i feel like comprehending them for useful action is an additional skill on top of learning to use git.
(DIR) Post #B18Rw5iHPWIRpfuxG4 by drj@typo.social
2025-12-11T09:53:24Z
0 likes, 0 repeats
@ricci fg like a true old-timer. I've been trying to get back into using it (i used it a lot when i first used unix in the 1990s, because it was often on a text-only terminal). I think it helps the concentration.