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I mean the low level protocol, not some framework, API or driver. In my ongoing quest to interface modern devices to very old 8 bit computers I have stumbled over this:
DEBO USB TTL: Raspberry Pi -USB-TTL-Schnittstellenwandler, CH340G bei reichelt elektronik[^]
Not really rocket science. With this I can send and receive bytes from a USB device with a simple UART. This would solve a few problems at once. A simple cheap memory stick would be all the hard disk' an 8 bit computer would ever need. Don't worry about speed. Mass storage is for many reasons a relatively slow affair on 8 bit computers, beginning with their low bandwith on the bus. Remember what Commodore did with the C64's floppy drives? I could also use a USB keyboard or a mouse.
So, with that converter and a UART I can now talk to USB devices. Can I also hook up a USB hub to it and access several USB devices over the same UART? How do I select devices? How do I request or send bytes? Some kind of USB protocol with an embedded device specific protocol?
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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I talk to it sometimes. Something along these lines: "Just get in to the slot you little..."
"It is easy to decipher extraterrestrial signals after deciphering Javascript and VB6 themselves.", ISanti[ ^]
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you realize they're all made overseas, they're pretty simple
... they don't understand English.
this internet has become nothing but fake news.
... time to fix it, time to get back to the fax!
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lw@zi wrote: I talk to it sometimes. Something along these lines: "Just get in to the slot you little..."
Has it ever responded with, "wrong way - flip me over"?
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That would be scary at first and then helpful. I can almost see another useless IoT device in the making.
"It is easy to decipher extraterrestrial signals after deciphering Javascript and VB6 themselves.", ISanti[ ^]
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Quote: "wrong way - flip me over"?
I had a girlfriend say that to me once, long, long ago.
- I would love to change the world, but they won’t give me the source code.
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If this were not the place it is, I would now ask you by which coordinate axis you flipped her over and if that was the right choice.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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It was the X coord. 
I really miss The Soapbox sometimes. 
- I would love to change the world, but they won’t give me the source code.
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 Whew, glad you didn't ask. 
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I was trying to be subtle...
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Twice, ironically.
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dandy72 wrote: Has it ever responded with, "wrong way - flip me over"?
Daily. I think my USB sticks need the Jeep warning:
If you can read this, flip me over.
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Looks neat, I just know PS2 ports are tough, never killed one, USB on the other hand I have blown up several occasions. I haven't tried low level reading with USB, I'm guessing it standard serial (bit in, shifted, byte full?) just a higher speeds... If memory serves Microchip did do a PDF on their web site that was quite helpful also Jan Axelsons USB complete is good, try looking at Jan Axelson's Lakeview Research She is quite good with communications stuff...
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PS/2 would be the other option for keyboard and mouse. It also uses a serial protocol, but in the lower kHz frequencies. I could probably program a PIC16FXXX to do that, but hooking up a PIC to an 8 bit bus is awkward. With 20 MHz the PIC is to slow to respond to signals on the bus in time. Still, I would try this if everything else fails. In the old days memories were to slow and had to delay the processor. Now it's slowpoky microcontrollers who need the same treatment. Nothing ever changes.
As for the mass storage: Serial ATA is a good candidate here. It's very much a direct read or write access from a 16 bit(!) bus to the drive's controller. With only an 8 bit bus things get slightly more complicated. Not that I want to dig out old obsolete hard disks. Compact flash memory cards use the serial ATA interface as well. One way or the other, I want a SSD for my old computer.
Edit: Look at this datasheet! A simple 8 bit parallel interface one one side and USB sticks or SD cards on the other. The commands to access the stick are also documented.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
modified 4-Dec-19 20:08pm.
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Something along the lines of "We both know you've been in a lot of different slots over the years. It is a miracle you are still virus free."?
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How dare you! That old computer has lived in perfect celibacy over the last 41 years! In Rome they already have it on their list for sainthood, but it's not dead yet and maybe we also need to perform one more miracle.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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That's why I insist my USB sticks always wear a condom.
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
AntiTwitter: @DalekDave is now a follower!
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Very gently.
"Five fruits and vegetables a day? What a joke!
Personally, after the third watermelon, I'm full."
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Quote: Stick 'm up punk!
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Put away Dirty Harry's .44 something! We are not in Texas here!
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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Sorry, was in a bad mood because so called "bugs" were reported that turned out to be part of the functionality, well they know how to keep me busy.
Good that I did not have a .44 at hand
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I don't know that a UART interface (RS232 or a variant?) would be fast enough to handle multiple sticks so that might be that your hardware adapter doesn't support device enumeration and always selects device 0. Not that an 8 bit device can keep up at the full rate anyway, but i'm more thinking from the manufacturer's standpoint here, not how you're using it particular. All speculative, but it's something to stick a mental pin in maybe.
I don't remember how to select devices with the USB protocol although i know the specs are available online (i've perused them before), much less over your adapter. Sorry.
I just thought i'd add the caveat above that it might not be possible with your interface, as i would hate to see you wind up on a wild goose chase.
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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It's a standard UART, as you would use for RS232, but without +/- 15V level shifting. This USB converter takes the TTL/CMOS level signals of the UART directly. Speed surprisingly is not much of a problem. This particular UART, a CDP1854, is specified to allow a whopping 200 kbit/sec as max. bitrate. Double that when you raise its second supply voltage to 10V. Not bad for a device from 1976. Back then they actually thought that CMOS was slow.
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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Wow, that's better than I expected. But your little 8bit monster can't keep up with that unless your clocking is insane haha. I ran a 56k baud modem in an old XT once just for grins (one of the rare ones that was small ISA) and the poor thing couldn't even operate at 33.6 
When I was growin' up, I was the smartest kid I knew. Maybe that was just because I didn't know that many kids. All I know is now I feel the opposite.
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No, it will not, despite going with a (then) ridiculous clock frequency of up to 6.4 MHz and, as one of the earliest CMOS processors, being famous for reckless overclocking decades before such things came into fashion on PCs. I just leave it to the UART's RTS/CTS signals to take care that not a single bit is lost and let the processor pick up the bytes as fast as it can. I can live with getting 'only' 100%. 
I have lived with several Zen masters - all of them were cats.
His last invention was an evil Lasagna. It didn't kill anyone, and it actually tasted pretty good.
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