5 ms·

USB had a quite successful precursor: RS-232. The serial standard is now 60 years old (!) and still much more widespread then USB in many industry machines.

by ktpsns 6y ago

exmadscientist 6y ago
And yet I wonder how many of those machines have USB to RS-232 converters internally... not that I've ever been asked to design such a thing.... Properly implemented RS-232 is a thing of beauty, in a way that USB just can't be. It's a shame so many implementations (of both!) fall short.
- myself248 6y ago
  The ones that barf out a debug console from the processor's first init steps are probably not USB internally. ;) But yeah, USB never came up with a good way to do peer-to-peer. On-the-go is super driver heavy and just not useful in the way RS232 is. New TVs still ship with it, for home automation reasons.
  - exmadscientist 6y ago
    And neither are they RS-232, unless you've got a transceiver (MAX232 etc) in there :) Man... USB CDC is painful. It's so much "fun" that a serious solution on one product was two back-to-back FTDI transceivers. I think they finally designed that out, but I'm scared to look at what might be in its place now....
    - myself248 6y ago
      https://www.tindie.com/products/8086net/usb-usb-null-modem-cdc/ https://www.tindie.com/products/8086net/usb-usb-null-modem-c... presented without comment
      - anitil 6y ago
        That is equally parts silly and useful. There's so many time's I wish I'd had one.
      - rleigh 6y ago
        Also https://www.ftdichip.com/Support/Documents/DataSheets/Cables/DS_USBNMC.pdf https://www.ftdichip.com/Support/Documents/DataSheets/Cables... They are genuinely useful.
- m463 6y ago
  Is it two lines with ^S/^Q/BREAK, or hardware flow control, with or without ring, db25->db9 converters (never of the right gender), etc... I was pretty happy to throw it out the window in favor of USB. Of course, firewire was better than usb and the whole cycle started again.
  - exmadscientist 6y ago
    One of the nice things about UARTs is that that's pretty much all there is to it. That is, it's about as much pain to implement as to use. USB CDC is worlds of pain more complicated to implement, but quite easy to use. As long as you don't hit a bug. But USB stacks never have bugs, do they?
  - buildbot 6y ago
    I've recently started working with firewire, and man what an interesting bus. You've got isochronous and asynchronous support simultaneously, awesome! But then you get this: "Voltage is specified as unregulated and should nominally be about 25 volts (range 24 to 30)" Looking at the nearest firewire device on my table, it will certainly blow up if I get near it with 25 volts. It's like USB-C without any negotiation!
    - nielsbot 6y ago
      I worked on the FireWire driver stack for OS X... and we encountered many incidents of managing to plug in the 6-pin connector upside down. Devices will actually catch fire. (FireWire carries up to 45W (!) at 30v) Also, isochronous mode is great in theory, but in practice, at least in a desktop computer, the rest of the machine internals are not isochronous so you can still run into real-time delivery failures.
      - emteycz 5y ago
        > Devices will actually catch fire. A rare case of successful naming, then.
      - m463 5y ago
fsckboy 6y ago
RS232 is the electrical signal standard; the chunky connector usually used is a DB25 but basic RS232 can fit in DB9 RJ11 (eg landline) and RJ45 (eg ethernet) were also connectors that achieved very widespread use, as did RG6 (eg cable tv) (I'm not going to say they changed the world and I'm also not so sure I like the grab-bag nature of the various things the article lists either for example, 8, 14 and 16 (and more) pin DIP were pretty important, or was it the TTL signals they carried or was it the connecting solder that ultimately made USB valuable... dumb article to write as a listicle.
- hug 6y ago
  If you are interested in being a pedant, which you may or may not be: What you call DB-9 is actually DE-9. (A DB-9 would be the size of a DB-25 but with only 9 pins, which would be weird.) What you call RJ11 is a 6p2c. (Six position, two connectors.) What you call an RJ45 is an 8p8c. (You can guess this one.)
  - wolfgang42 6y ago
    To expand on the pedanticness: The letter in the D-subminiature line (aside: they really didn’t anticipate how small connectors were going to become) refers to the shell size (A through E, though not in size order). “DB” is frequently used colloquially as a prefix for any size in the line. There’s also some interesting variants like the DB13W3, which is a B-size shell containing 10 ordinary pins plus 3 coax connectors. RJ11/RJ45 refer to the connectors and the way they’re wired, together. For example, RJ14 is the same 6p connector as RJ11 but wired to support two phone lines instead of just one, and the same 8p8c connector we’d use for Ethernet but wired for 4 phone lines would be an RJ61.
    - aYsY4dDQ2NrcNzA 6y ago
      I fully expect another pedant to respond to this, any minute now.
    - throw0101a 5y ago
      Article: * https://en.wikipedia.org/wiki/D-subminiature https://en.wikipedia.org/wiki/D-subminiature
dan_hawkins 5y ago
Actually the more appropriate predecessor of USB is 8-bit Atari SIO: https://en.wikipedia.org/wiki/Atari_SIO https://en.wikipedia.org/wiki/Atari_SIO
- davidgould 5y ago
  No love for Apple Desktop Bus?
  - dan_hawkins 5y ago
    Atari was way earlier.

USB had a quite successful precursor: RS-232. The serial standard is now 60 years old (!) and still much more widespread then USB in many industry machines.

by ktpsns 6y ago

USB had a quite successful precursor: RS-232. The serial standard is now 60 years old (!) and still much more widespread then USB in many industry machines.

exmadscientist 6y ago

And yet I wonder how many of those machines have USB to RS-232 converters internally... not that I've ever been asked to design such a thing.... Properly implemented RS-232 is a thing of beauty, in a way that USB just can't be. It's a shame so many implementations (of both!) fall short.

myself248 6y ago
The ones that barf out a debug console from the processor's first init steps are probably not USB internally. ;) But yeah, USB never came up with a good way to do peer-to-peer. On-the-go is super driver heavy and just not useful in the way RS232 is. New TVs still ship with it, for home automation reasons.
- exmadscientist 6y ago
  And neither are they RS-232, unless you've got a transceiver (MAX232 etc) in there :) Man... USB CDC is painful. It's so much "fun" that a serious solution on one product was two back-to-back FTDI transceivers. I think they finally designed that out, but I'm scared to look at what might be in its place now....
  - myself248 6y ago
    https://www.tindie.com/products/8086net/usb-usb-null-modem-cdc/ https://www.tindie.com/products/8086net/usb-usb-null-modem-c... presented without comment
    - anitil 6y ago
      That is equally parts silly and useful. There's so many time's I wish I'd had one.
    - rleigh 6y ago
      Also https://www.ftdichip.com/Support/Documents/DataSheets/Cables/DS_USBNMC.pdf https://www.ftdichip.com/Support/Documents/DataSheets/Cables... They are genuinely useful.
m463 6y ago
Is it two lines with ^S/^Q/BREAK, or hardware flow control, with or without ring, db25->db9 converters (never of the right gender), etc... I was pretty happy to throw it out the window in favor of USB. Of course, firewire was better than usb and the whole cycle started again.
- exmadscientist 6y ago
  One of the nice things about UARTs is that that's pretty much all there is to it. That is, it's about as much pain to implement as to use. USB CDC is worlds of pain more complicated to implement, but quite easy to use. As long as you don't hit a bug. But USB stacks never have bugs, do they?
- buildbot 6y ago
  I've recently started working with firewire, and man what an interesting bus. You've got isochronous and asynchronous support simultaneously, awesome! But then you get this: "Voltage is specified as unregulated and should nominally be about 25 volts (range 24 to 30)" Looking at the nearest firewire device on my table, it will certainly blow up if I get near it with 25 volts. It's like USB-C without any negotiation!
  - nielsbot 6y ago
    I worked on the FireWire driver stack for OS X... and we encountered many incidents of managing to plug in the 6-pin connector upside down. Devices will actually catch fire. (FireWire carries up to 45W (!) at 30v) Also, isochronous mode is great in theory, but in practice, at least in a desktop computer, the rest of the machine internals are not isochronous so you can still run into real-time delivery failures.
    - emteycz 5y ago
      > Devices will actually catch fire. A rare case of successful naming, then.
    - m463 5y ago

fsckboy 6y ago

RS232 is the electrical signal standard; the chunky connector usually used is a DB25 but basic RS232 can fit in DB9 RJ11 (eg landline) and RJ45 (eg ethernet) were also connectors that achieved very widespread use, as did RG6 (eg cable tv) (I'm not going to say they changed the world and I'm also not so sure I like the grab-bag nature of the various things the article lists either for example, 8, 14 and 16 (and more) pin DIP were pretty important, or was it the TTL signals they carried or was it the connecting solder that ultimately made USB valuable... dumb article to write as a listicle.

hug 6y ago
If you are interested in being a pedant, which you may or may not be: What you call DB-9 is actually DE-9. (A DB-9 would be the size of a DB-25 but with only 9 pins, which would be weird.) What you call RJ11 is a 6p2c. (Six position, two connectors.) What you call an RJ45 is an 8p8c. (You can guess this one.)
- wolfgang42 6y ago
  To expand on the pedanticness: The letter in the D-subminiature line (aside: they really didn’t anticipate how small connectors were going to become) refers to the shell size (A through E, though not in size order). “DB” is frequently used colloquially as a prefix for any size in the line. There’s also some interesting variants like the DB13W3, which is a B-size shell containing 10 ordinary pins plus 3 coax connectors. RJ11/RJ45 refer to the connectors and the way they’re wired, together. For example, RJ14 is the same 6p connector as RJ11 but wired to support two phone lines instead of just one, and the same 8p8c connector we’d use for Ethernet but wired for 4 phone lines would be an RJ61.
  - aYsY4dDQ2NrcNzA 6y ago
    I fully expect another pedant to respond to this, any minute now.
  - throw0101a 5y ago
    Article: * https://en.wikipedia.org/wiki/D-subminiature https://en.wikipedia.org/wiki/D-subminiature

dan_hawkins 5y ago

Actually the more appropriate predecessor of USB is 8-bit Atari SIO: https://en.wikipedia.org/wiki/Atari_SIO https://en.wikipedia.org/wiki/Atari_SIO

davidgould 5y ago
No love for Apple Desktop Bus?
- dan_hawkins 5y ago
  Atari was way earlier.