4 ms·

ADB was basically USB 0.1: 5-volt multi-device serial bus for desktop peripherals, polled by the host, with dynamic addressing and standard device classes. The

ADB was basically USB 0.1: 5-volt multi-device serial bus for desktop peripherals, polled by the host, with dynamic addressing and standard device classes. The only thing it was missing was hot-plugging. (The protocol could handle it, but there were mechanical/electrical issues that made it hazardous to try.) They even had a connector that made it hard to tell if you were trying to plug it in upside down!

adrianmonk 6y ago
With the connector itself, it was hard to tell, but the plastic part you held in your hand (molded plastic plus strain relief) wasn't symmetrical. You could thus develop a habit of putting, say, the flat part next to your thumb, and then you'd know the alignment of the cable. So if you knew the alignment of port, you could do reliably on the first attempt. USB makes a slightly worse mistake, which is that the plastic part you hold in your hand feels the same way if you turn it around 180 degrees. So you have to point it at your face and look at it if you want to know which way you're holding it.
- twic 6y ago
  I think all of the USB-A jacks i have are made out of a sheet of metal folded over on itself, with the join on the bottom. You can tell which way up a jack is by looking for the join. See this picture of some random bitcoin gizmo: https://www.ccn.com/wp-content/uploads/2014/11/usb-top-bottom-together.png https://www.ccn.com/wp-content/uploads/2014/11/usb-top-botto... It's certainly not as easy as with ADB, but it only takes a quick glance to orient a USB jack. I can't be the only person to have noticed this.
  - moftz 6y ago
    The part that screws me up is whenever the USB port is upside down, meaning the plug goes in with the retention holes facing down.
kalleboo 6y ago
It also presaged using the bus as a handy source of 5V power - I have a SCSI Ethernet adapter for PowerBook notebooks that gets its power from a separate pass thru cable you need to plug into the ADB port.
- fzzzy 6y ago
  I have one of those SCSI Ethernet adapters as well. We used to use a desktop computer with a modem running Vicom Internet Gateway, and then share that single modem connection with other computers over Ethernet. For multiple people chatting on virtual worlds at the same time, it worked fine!
spacedcowboy 6y ago
ADB was maybe 0.5.. The progenitor of USB was the SIO interface on the Atari 8-bit series. (https://en.wikipedia.org/wiki/Atari_SIO https://en.wikipedia.org/wiki/Atari_SIO) The inventor of SIO (Joe Decuir) was also part of the USB team, and credits SIO as having a big influence on USB. SIO was actually pretty neat, for those early days, it was effectively an implementation of a serial-based virtual-filesystem-like layer, where a device I/O block held pointers to routines for read-char/write-char/open/close/.../xio (where xio was the catch-all, like ioctl()) You could create your own SIO drivers, or load in 3rd-party drivers (the floppy-disk driver was a loaded SIO driver) , and the machine came with some already installed by the OS (keyboard, screen, cassette i/o, printer). Any external device would plug into the SIO port in the back of the machine, which was molded so it only went in one way. SIO as a software API wasn’t limited to the external bus, either. Atari introduced an 80-column box (the XEP-80) which used the SIO api internally to drive 8-bit parallel data across the bidirectional joystick ports (yes, the 80-column card connected via the joystick ports, because if you were running with 80-column text, apparently you never played games...) The joystick ports gave a higher bandwidth than the SIO port, but there was a parallel port on the XL/XE as well... Of course, the requirements for 8-bit computers were a lot lower, so the bus ran at the blazing speed of 19200 baud normally (you could boost it higher, up to 72k), and the entire thing was run off the clock-domain of POKEY, the sound chip. There was a lot of neat engineering in the Atari 8-bit line, most of which was ignored because it was a “games computer”...

adrianmonk 6y ago

With the connector itself, it was hard to tell, but the plastic part you held in your hand (molded plastic plus strain relief) wasn't symmetrical. You could thus develop a habit of putting, say, the flat part next to your thumb, and then you'd know the alignment of the cable. So if you knew the alignment of port, you could do reliably on the first attempt. USB makes a slightly worse mistake, which is that the plastic part you hold in your hand feels the same way if you turn it around 180 degrees. So you have to point it at your face and look at it if you want to know which way you're holding it.

twic 6y ago
I think all of the USB-A jacks i have are made out of a sheet of metal folded over on itself, with the join on the bottom. You can tell which way up a jack is by looking for the join. See this picture of some random bitcoin gizmo: https://www.ccn.com/wp-content/uploads/2014/11/usb-top-bottom-together.png https://www.ccn.com/wp-content/uploads/2014/11/usb-top-botto... It's certainly not as easy as with ADB, but it only takes a quick glance to orient a USB jack. I can't be the only person to have noticed this.
- moftz 6y ago
  The part that screws me up is whenever the USB port is upside down, meaning the plug goes in with the retention holes facing down.

kalleboo 6y ago

It also presaged using the bus as a handy source of 5V power - I have a SCSI Ethernet adapter for PowerBook notebooks that gets its power from a separate pass thru cable you need to plug into the ADB port.

fzzzy 6y ago
I have one of those SCSI Ethernet adapters as well. We used to use a desktop computer with a modem running Vicom Internet Gateway, and then share that single modem connection with other computers over Ethernet. For multiple people chatting on virtual worlds at the same time, it worked fine!

spacedcowboy 6y ago

ADB was maybe 0.5.. The progenitor of USB was the SIO interface on the Atari 8-bit series. (https://en.wikipedia.org/wiki/Atari_SIO https://en.wikipedia.org/wiki/Atari_SIO) The inventor of SIO (Joe Decuir) was also part of the USB team, and credits SIO as having a big influence on USB. SIO was actually pretty neat, for those early days, it was effectively an implementation of a serial-based virtual-filesystem-like layer, where a device I/O block held pointers to routines for read-char/write-char/open/close/.../xio (where xio was the catch-all, like ioctl()) You could create your own SIO drivers, or load in 3rd-party drivers (the floppy-disk driver was a loaded SIO driver) , and the machine came with some already installed by the OS (keyboard, screen, cassette i/o, printer). Any external device would plug into the SIO port in the back of the machine, which was molded so it only went in one way. SIO as a software API wasn’t limited to the external bus, either. Atari introduced an 80-column box (the XEP-80) which used the SIO api internally to drive 8-bit parallel data across the bidirectional joystick ports (yes, the 80-column card connected via the joystick ports, because if you were running with 80-column text, apparently you never played games...) The joystick ports gave a higher bandwidth than the SIO port, but there was a parallel port on the XL/XE as well... Of course, the requirements for 8-bit computers were a lot lower, so the bus ran at the blazing speed of 19200 baud normally (you could boost it higher, up to 72k), and the entire thing was run off the clock-domain of POKEY, the sound chip. There was a lot of neat engineering in the Atari 8-bit line, most of which was ignored because it was a “games computer”...