[HN Gopher] Bit-banging a BASIC Birthday
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       Bit-banging a BASIC Birthday
        
       Author : debo_
       Score  : 107 points
       Date   : 2024-08-19 11:57 UTC (11 hours ago)
        
 (HTM) web link (thingswemake.com)
 (TXT) w3m dump (thingswemake.com)
        
       | pvg wrote:
       | https://web.archive.org/web/20240819124125/https://thingswem...
       | in case of site flakiness
       | 
       | the repo linked in the article:
       | https://github.com/joshsucher/mts-70
        
       | max-m wrote:
       | The Blog was hugged to death, but https://archive.is/1FrpD got
       | through.
        
       | michaelmior wrote:
       | Very cool! I can't imagine how this wouldn't be one of the best
       | gifts ever received.
       | 
       | s/heartiness/hardiness/
        
       | sgt wrote:
       | Very impressive!
        
       | mananaysiempre wrote:
       | s/Basic/BASIC/ (HN's title autodestroy strikes again)
        
       | deivid wrote:
       | Amazing! I love projects that bring some new features to classic
       | hardware; I did something similar for my dad's 50th birthday[0].
       | 
       | [0]: https://blog.davidv.dev/posts/revamping-an-old-tv-as-a-gift
        
         | Pompidou wrote:
         | A 50 years old man is indeed a classic piece of hardware.
        
       | bitwize wrote:
       | As dodgy as the early Tandy stuff's reputation was as
       | "TRASH-80s", it's no surprise that OP's dad loved them. Back in
       | the day, Tandy machines really did deliver value for money. Of
       | course once you popped them open, their manufacturing-design
       | issues would be revealed. There were bodgewires all over the
       | place because of last-minute issues found after the PCBs had gone
       | to manufacturing. And the ones with built-in CRTs had issues
       | wherein the cathode of the CRT was DANGEROUSLY CLOSE to the main
       | PCB. If you weren't careful cracking that puppy open -- zappo!
       | Fried motherboard, possibly fried you!
       | 
       | For these reasons, and possibly also to hide their shame and
       | embarrassment and make extra scratch on service calls, Tandy
       | equipment often had one of those "Warranty void if seal is
       | broken" stickers on it, which are now illegal to enforce even in
       | the USA. They also used to seal the screwholes with Glyptal to
       | prevent unauthorized tinkering; this so incensed my dad that he
       | called all the way up the chain to the president of Tandy Corp.
       | to make them stop (and also drilled through the Glyptal to get at
       | the screws).
       | 
       | But when it worked, it was solid, not to mention cheap. Great
       | stuff for hobbyists and even small businesses.
        
         | ansible wrote:
         | This is an interesting and fun project, I was glad to read
         | about it.
         | 
         | It was a bit of a bold move to base this on a Model I. That
         | system had an unreliable expansion interface, limited memory
         | options, and emitted a lot of EM interference.
        
         | codewritinfool wrote:
         | >And the ones with built-in CRTs had issues wherein the cathode
         | of the CRT was DANGEROUSLY CLOSE to the main PCB. If you
         | weren't careful cracking that puppy open -- zappo! Fried
         | motherboard, possibly fried you!
         | 
         | I'm curious which model this was. The Model III was the first
         | all-in-one model I had experience with, and the between the
         | motherboard and the CRT neck was a piece of flat aluminum. The
         | biggest danger was potentially snapping the neck off, but there
         | was no danger of touching the mother board. Model 4 was the
         | same configuration. Even the Model II had a metal plate between
         | the CRT and any circuit boards.
        
       | jonjack wrote:
       | respect the buc-ees shirt
        
       | anonymousiam wrote:
       | The author mentions that some programs have made sound with the
       | TRS-80 by using tight timing loops that access the bus(es), which
       | create a lot of RFI that can be received by a nearby AM radio
       | tuned off-station. The software loops can be timed to produce
       | musical notes that will be heard (along with much static) on the
       | radio. Looks like he used the cassette outputs directly for sound
       | in this case.
       | 
       | I noticed that the video link on his web page was not a
       | hyperlink. His video is here:
       | https://www.youtube.com/shorts/JD9sXwgHMfc
       | 
       | I never owned a desktop TRS-80, but I repaired one once after a
       | friend of mine inadvertently put 120VAC on the internal 5V power
       | bus. About 1/3 of the chips were blown.
       | 
       | He told me how he blew it up: The Condor power supply he was
       | using to provide +/- 12VDC needed for the RS-232 EIA voltages to
       | drive his modem had the input (line voltage) present on a the
       | same terminal strip with the +/- 12VDC output terminals. After a
       | few beers, he had dropped some metal object (bottle opener?) and
       | it momentarily bridged the 120VAC and one of the 12VDC outputs.
       | The line voltage found its way through one of the 1488/1489 EIA
       | converters, and onto the 5VDC bus. That was enough to let the
       | "magic smoke" out of about a third of the chips.
       | 
       | https://en.wikipedia.org/wiki/Magic_smoke
       | 
       | I do still have a TRS-80 Model 100 in a closet somewhere.
       | 
       | https://en.wikipedia.org/wiki/TRS-80_Model_100
        
       | wang_li wrote:
       | I may be getting old but it may be that the enjoyment dad is
       | going to get from this is less than if he'd spent this amount of
       | time with dad instead of making a doodad for dad to futz with.
        
       | ForOldHack wrote:
       | A Whopping 32k on an expansion card! Triple the memory expansion.
       | This is like going from 32Gs to 96Gs, because 64Gbs was just not
       | enough.
       | 
       | "a 48 K machine would have been a very unusually powerful one for
       | 1978." After 1978, it was almost the standard.
        
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       (page generated 2024-08-19 23:00 UTC)