Atari SIO Questions

[Xebec]

Just a few questions --

 

1. Why was the SIO plug 'so large', and not something more compact like the 9-pin joystick connector? I know SIO needs 13-pins instead of 9, but just curious if there is an electrical reason why it's substantially larger.

 

2. Was there ever any consideration for making a version of this for Amiga Lorraine - as SIO (daisy chainable, smart devices, with 5V/12V power for low power devices) is awesome. I'm guessing either SIO was patented, or "Lorraine is a gaming system" (though so was the original design of the Atari chipset).

 

3. Are there any other computers with a SIO / USB type functionality, prior to actual USB on PCs from the mid/late 1990s?

 

Thanks

John

[+slx]

1. Why was the SIO plug 'so large', and not something more compact like the 9-pin joystick connector? I know SIO needs 13-pins instead of 9, but just curious if there is an electrical reason why it's substantially larger.

 

Probably because it was to be "idiot-proof". It's much easier and intuitive to use and looks a lot less technical than the "standard" connectors of the era. Centronics plugs used those technical-looking metal clamps and the larger DB-15, etc. plugs needed screws to stay in and the pins were much easier to bend. The large SIO plugs could probably be handled by 5-year-old and had enough friction to stay put without clamps or screws.

 

2. Was there ever any consideration for making a version of this for Amiga Lorraine - as SIO (daisy chainable, smart devices, with 5V/12V power for low power devices) is awesome. I'm guessing either SIO was patented, or "Lorraine is a gaming system" (though so was the original design of the Atari chipset).

Only an educated guess here, but there should be people who can answer this.

 

By the time the Amiga came out there was a much larger and specialized market for peripherals, the Centronics parallel port was the de facto standard for printers and DB-9 RS-232 for modems. There was much less need for a computer manufacturer to provide all peripherals and it was probably less likely for customers to buy everything from one manufacturer, especially with a high-end machine like the Amiga (even most Atari printers were just so-so and not top of the line). Amiga didn't have the clout to push a SIO-plus bus into the market, it was quite some time later that USB achieved that.

 

3. Are there any other computers with a SIO / USB type functionality, prior to actual USB on PCs from the mid/late 1990s?

 

All following was found on Wikipedia.

 

HP-IB (IEE 488) predated SIO and was used on the Commodore PET and was available as an option on the VIC-20 and C64 (both of which used the IEE 488 protocol over a serial connection).

 

Maybe the Apple Desktop Bus (ADB) might qualify, although it was for keyboard / mice only AFAIK, and HP had HP-IL, which worked on all kinds of peripherals with very small connectors. On HP-IL all connections formed a loop, i.e. all devices were daisy-chained and the cabling needed to be run back to the host device form the last device on the chain.

 

Wikipedia also lists Access.bus which I've never heard of, though I (like most people who lived through the pre-HDMI-age) seem to have used it nevertheless as it was (and still is) used on VGA connections to communicate the display specs to the computer.

[Xebec]

Great reply six!

 

#1 makes a lot of sense.. makes the computer 'easier to use' for anyone. And the 400/800 was pretty friendly..

 

#3 - great list; was reviewing. The HP-IB Is interesting though it doesn't carry power for peripherals like SIO/USB, The other two (1986 and "early 1990s") standards do carry power though.. good finds and thank you.

 

Thanks!

 

Probably because it was to be "idiot-proof". It's much easier and intuitive to use and looks a lot less technical than the "standard" connectors of the era. Centronics plugs used those technical-looking metal clamps and the larger DB-15, etc. plugs needed screws to stay in and the pins were much easier to bend. The large SIO plugs could probably be handled by 5-year-old and had enough friction to stay put without clamps or screws.

Only an educated guess here, but there should be people who can answer this.

By the time the Amiga came out there was a much larger and specialized market for peripherals, the Centronics parallel port was the de facto standard for printers and DB-9 RS-232 for modems. There was much less need for a computer manufacturer to provide all peripherals and it was probably less likely for customers to buy everything from one manufacturer, especially with a high-end machine like the Amiga (even most Atari printers were just so-so and not top of the line). Amiga didn't have the clout to push a SIO-plus bus into the market, it was quite some time later that USB achieved that.

 

All following was found on Wikipedia.

 

HP-IB (IEE 488) predated SIO and was used on the Commodore PET and was available as an option on the VIC-20 and C64 (both of which used the IEE 488 protocol over a serial connection).

 

Maybe the Apple Desktop Bus (ADB) might qualify, although it was for keyboard / mice only AFAIK, and HP had HP-IL, which worked on all kinds of peripherals with very small connectors. On HP-IL all connections formed a loop, i.e. all devices were daisy-chained and the cabling needed to be run back to the host device form the last device on the chain.

 

Wikipedia also lists Access.bus which I've never heard of, though I (like most people who lived through the pre-HDMI-age) seem to have used it nevertheless as it was (and still is) used on VGA connections to communicate the display specs to the computer.

[Rybags]

Proprietary plugs were all the rage in the 70s and 80s. Makes it harder for competitors to jump in and make a profit on peripherals.

 

And the automation of the day wasn't like today - though supposedly there's a fair bit of human intervention required in the making of micro USB and especially USB-C connectors.

 

But yes, they could have made it smaller but if they'd used something like the ST monitor DIN plug it would have broken all the time as it's a bit delicate.

[Kyle22]

SIO has been proven to be the perfect solution. 40 years later most SIO cables are still good. How long does your Micro USB cable last? 6 months for a cheap one, a year or 2 MAX for a 'good' one.

[Rybags]

And microUSB has only the 4 connections, and the USB 3 ones are one of the most annoying things you'll ever use.

[Kyle22]

And microUSB has only the 4 connections, and the USB 3 ones are one of the most annoying things you'll ever use.

You mean Type C? They may be inserted either way, just like Apple Lightning connector.

I HAVE seen type C phones go loose and not charge. Not quite as bad as Micro-USB, but no where close to perfect!

[ijor]

SIO has been proven to be the perfect solution. 40 years later most SIO cables are still good. How long does your Micro USB cable last? 6 months for a cheap one, a year or 2 MAX for a 'good' one.

 

SIO is a great design, but I don't think that is a fair comparison.

 

SIO cables are pretty much static, you don't connect and disconnect them as frequently as an USB cable. Many people hold the phone, or at least the charger, from the cable. You don't hold your computer or your 1050 drive from the SIO cable, do you? Lastly, USB cables could probably be much more reliable if you wouldn't mind them being as heavy and bulky as a SIO cable. But most people prefer them very light and cheap, even if you must replace them every year.

Edited April 8, 2019 by ijor

[+Nezgar]

You mean Type C? They may be inserted either way, just like Apple Lightning connector.

I HAVE seen type C phones go loose and not charge. Not quite as bad as Micro-USB, but no where close to perfect!

 

I agree type C is great... But I think Rybags is referring to the fugly USB-3 "superspeed" types:

https://hosatech.com/wp-content/uploads/2013/12/SuperSpeed_USB_3.0_Hi.jpg

[Daedalus2097]

As for the Amiga portion of the question, it didn't have the same general purpose capability as SIO, but the Amiga's external floppy drive port allows daisy-chaining of floppy drives up to a limit of 3 extra drives. As said, other peripherals were taken care of by serial, parallel, and later SCSI (and later still IDE) interfaces.

[FifthPlayer]

In the ANTIC podcast interview with Joe Decuir, he recounts some of the history behind SIO. They wanted an Apple II-style card bus for expansion, but FCC regulations regarding EMI interference were so strict at the time they opted to build a serial bus instead for peripherals. Once they made that decision, they were locked into making a full line of house-branded peripherals for the computer.

 

I'm not so sure the SIO plugs and connectors are completely foolproof. The female connector is on the computer itself and has many small fragile pins. I managed to squash one of those pins on my 800 BITD by carelessly plugging in something, and had to use a needle-nose pliers to straighten it out. That was pretty scary.

[Gunstar]

 

SIO is a great design, but I don't think that is a fair comparison.

 

SIO cables are pretty much static, you don't connect and disconnect them as frequently as an USB cable. Many people hold the phone, or at least the charger, from the cable. You don't hold your computer or your 1050 drive from the SIO cable, do you? Lastly, USB cables could probably be much more reliable if you wouldn't mind them being as heavy and bulky as a SIO cable. But most people prefer them very light and cheap, even if you must replace them every year.

I don't hold my phone or USB chargers by the cable either...only morons do that, IMHO.

[ivop]

The large SIO plugs could probably be handled by 5-year-old and had enough friction to stay put without clamps or screws.

 

Most Ataris and SIO plugs I have handled had so much friction, five year olds probably didn't have enough strength to put them

[Kyle22]

Most Ataris and SIO plugs I have handled had so much friction, five year olds probably didn't have enough strength to put them

That's a good thing. I don't want a five year old pulling out my SIO cable.

 

[SS]

I don't hold my phone or USB chargers by the cable either...only morons do that, IMHO.

I don't treat my phone with even close to the same reverence that I do my Ataris.