[HN Gopher] The Apple II Yellowstone Floppy Interface
___________________________________________________________________
The Apple II Yellowstone Floppy Interface
Author : zdw
Score : 78 points
Date : 2022-11-06 21:51 UTC (1 days ago)
(HTM) web link (nicole.express)
(TXT) w3m dump (nicole.express)
| sbf501 wrote:
| > That's right, this is actually a look at a product being sold
| at the time of this writing, the Yellowstone controller card:
|
| I'm not surprised. I shelled out $80 bucks for a null modem RS232
| cable and two packs of Verbatim 5.25" floppies, sealed, from the
| 1980's, so that I could get my Apple //e running again.
| Ironically I never knew the SuperSerial card could turn the Apple
| into a dumb terminal: now I can copy Apple //e disk images from
| my Mac, via serial, to the target 5.25" drives. I mean, it's
| obvious now, but it never occurred to me in the 80's.
|
| The design of this card is better too because it has plug
| polarity. I had to replace a buffer chip on one of the drives
| because the original Apple ribbon cable socket didn't have a
| polarity (or collar) and I accidentally installed the cable
| shifted right one pair of pins. Powered up, heard a loud crack,
| and when I opened the drive, there was a 14-pin DIP cracked in
| half and blackened.
|
| Also, that "Total Replay" screen is hilarious. What a mashup.
| CamperBob2 wrote:
| _I mean, it 's obvious now, but it never occurred to me in the
| 80's._
|
| What's really going to bake your noodle is when someone tells
| you your Apple had a 1200-baud modem built in at the factory.
| sbf501 wrote:
| Huh? Where?
| skissane wrote:
| The cassette interface.
| EvanAnderson wrote:
| The cassette interface is a type of modem. It's not a
| telephone modem, but it is modulating and demodulating
| digital data to/from analog.
| sbf501 wrote:
| You have absolutely baked my noodle.
|
| /golf clap/
| CamperBob2 wrote:
| Interestingly, all it takes to turn it into a telephone
| modem is a hybrid network from an old phone and a couple
| of LM386-grade audio amps.
|
| Not exactly Bellcore-202 spec, but it was good enough to
| send Strip Poker pics to a friend across town.
| EvanAnderson wrote:
| And a makeshift audio digitizer!
| user3939382 wrote:
| I have an Apple IIc but I have a hard time finding 5 1/4s for
| it. The ones I do find seem like they almost never work, maybe
| because of age. I'm not sure.
|
| If anyone that's into this type of retro computing has any tips
| for getting reliable IO/disks with these old machines I would
| appreciate it.
| toast0 wrote:
| One thing to be aware of is high density floppies are
| unlikely to work. You've got to make sure you get double
| density (aka low density, but I guess there was some
| abandoned standard that was lower than double). I've got a
| bunch pulled from that one time my dad broke our Tandy 1000
| TL/2's floppy port and the 3.5" ds/dd drive stopped working,
| but we still had the 5.25" ds/dd drive running, and a lucky
| find at WeirdStuff. But I've got the problem that even though
| the disks are double sided, I can't use the backsides because
| I don't have a notcher and I'm not using scissors. :( Also,
| something happened to my monitor recently, and now it only
| blows fuses and doesn't display things anymore :((
|
| If you're in the Seattle area, email me (on profile) and I
| can give you some disks, but I'm not gonna mail them.
| sbf501 wrote:
| Here is what I purchased:
|
| https://retrofloppy.com/products/#BlankDisks
|
| They seem to be working fine. I used 5 out of 20 so far.
| krallja wrote:
| https://www.floppydisk.com/5point25 is, as far as I can tell,
| the only reliable seller of floppy disks left on the planet.
| zackbloom wrote:
| > I went out of my way to feed the Apple ][ video into the
| luminance pin of an S-Video port for this segment to make the
| text more readable at the expense of color.
|
| I found this to be the most interesting part of the whole post,
| I'd love to see a schematic of how that works.
| nicole_express wrote:
| It's pretty easy to get a breakout cable for chrominance and
| luminance separately into an S-Video port; at that point I just
| plugged in the Apple II's output into luminance and left
| chrominance unconnected.
|
| This works particularly well on the Apple II because all of its
| color actually comes from creating dot patterns that cause
| luminance to interfere with decoding of chrominance, it has no
| "real" chrominance signal.
| krallja wrote:
| The schematic would just be a wire connecting two pins.
| RCA Mini DIN __________________________
| COMP o--------o LUM --------o CHROM GND
| o--------o GND
|
| S-Video has two pins (plus ground): luminance and chrominance.
| Composite has only one pin (plus ground). A composite video
| signal is a hack (for backwards compatibility with B&W TV) that
| has both of these signals (and some timing signals, called
| "sync", which happen outside the visible area of the image)
| combined together into a single "composite" waveform. De-
| composing the two signals is what causes color bleed and color
| artifacts with NTSC color images: it's not easy for a monitor
| to reverse the math, especially on abrupt brightness edges
| (like the kind computer pixels are prone to causing, with their
| decidedly discrete color transitions), since they look an awful
| lot like the color carrier shifting phase.
|
| S-Video is exactly the same two visible signals as a composite
| image, but the color data gets its own dedicated pin. So, if
| you send a black and white composite signal on the luminance
| pin, and no signal at all on chroma, you get a completely clear
| B&W picture output, with 0 color bleed (since there is no color
| information).
| duskwuff wrote:
| Some early computer monitors had a "mono/color" switch which
| could disable chroma separation. Set to "mono" for text mode;
| "color" for games. :)
| scarface74 wrote:
| I think my Mac LCII/Apple //e card/5.25 disk drive combination is
| still in a closet somewhere at my parents house. I know my
| collection of 5.25 disks are still in my old bedroom under a
| desk.
|
| I keep meaning to get my setup and seeing if I can get it up and
| running. But then again, I keep struggling with why? For
| nostalgia, I can find most of the images on the internet and run
| them on an emulator.
| Gracana wrote:
| That's a cool machine to have. Hopefully the motherboard hasn't
| been corroded by a leaky battery and/or capacitors. That's the
| common fate of 90s Macintoshes. It's often repairable, but it
| can take considerable effort to rework and repair a board with
| traces and vias and IC legs eaten by acid.
| scarface74 wrote:
| And I also had a copy of SoftPC with it to run my DOS based
| compilers for college.
|
| Ironically enough my next computer two years later was a PPC
| 6100/60 with a DOS Compatibility card. That should also be at
| my parents house somewhere.
___________________________________________________________________
(page generated 2022-11-07 23:01 UTC)