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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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forgive me if i missed it somewhere, but which CPU are you using?
6502 holds a special place in my black little 8 bit heart.
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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Memory sticks use the USB protocol, which is available at www.usb.org. The higher-level software protocol is typically USB attached SCSI (UAS), available from the same place.
I don't know what protocol is used for mice, keyboards, or hubs, but I'm sure that you can find it on the site as well.
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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yup, and AIUI it's a fairly complex protocol to implement properly; you can't just bitbang it via a simple GPIO pin on a microcontroller.
To bridge a retroPC to a USb stick what you probably would need to do is to have an RPi/etc that speaks both RS232 (or that can bit-bang whatever retro-protocol that the target computer expects to get its IO on) and USB; and then write an application on it that can translate from USB to retro IO.
Did you ever see history portrayed as an old man with a wise brow and pulseless heart, weighing all things in the balance of reason?
Is not rather the genius of history like an eternal, imploring maiden, full of fire, with a burning heart and flaming soul, humanly warm and humanly beautiful?
--Zachris Topelius
Training a telescope on one’s own belly button will only reveal lint. You like that? You go right on staring at it. I prefer looking at galaxies.
-- Sarah Hoyt
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Dan Neely wrote: To bridge a retroPC to a USb stick what you probably would need to do is to have an RPi/etc that speaks both RS232 (or that can bit-bang whatever retro-protocol that the target computer expects to get its IO on) and USB; and then write an application on it that can translate from USB to retro IO.
Look at the adapter module that I posted the link to. It's actually intended to be used with a Raspy. The conversion magic is done in the lonely chip on the small board. On one side you have the USB port and on the other side you have the four signals for a UART plus ground, at TTL/CMOS levels and not shifted to RS232 levels. That should work with any UART, 8 bit computer or not.
Provided that works as advertised, the big question is what I will have to send over my UART and what response I will get. Maybe I should look for some Raspy users to tell me what they use the adapter for and how they access the USB devices with it.
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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Whatever you do, during the conversation, don't mention it's size. Memory sticks hate that.
Also, avoid the question "Does my capacity look big in this USB port?"
It's a trick question that can never be answered to the memory stick's satisfaction.
".45 ACP - because shooting twice is just silly" - JSOP, 2010 ----- You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010 ----- When you pry the gun from my cold dead hands, be careful - the barrel will be very hot. - JSOP, 2013
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That's not the worst. Memory sticks never forget any of your mistakes and also store the exact date and time of every (non)event. Just forget any one of them and you suddently must sleep on your couch or in the dog house.
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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Forgive me, but how exactly do you think that USB interface device will help you?
That interface device functions as a USB client. What you need is a device that can function as a USB host.
The memory stick would be the client and the host device is what would talk to it and relay the information to your 8-bit.
The difficult we do right away...
...the impossible takes slightly longer.
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Thanks. I had to find the datasheet of the chip on the adapter to finally find out what it is for. Like you say, the USB side goes to a PC, which then is the host and the UART side of the adapter goes to a client that only has a UART and can then act as a USB client.
It would have been too easy. Back to plan B then. PS/2 for keyboard and mouse, serial ATA to access compact flash memory cards.
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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The device in the link is something very different than what you are looking for.
Remember that USB has devices with Master role; tose are usally the hosts that initate and manage all the comunication on the bus. Then there are Slave devices that respond to master's requests and send out data in an orderly manner, when instructed to do so.
The device you are referring is of the latter type; it can only reply to a host requests and it can't talk to other USB devices. What you want to implement is a master node.
As you may have understood, the master has very complex tasks to accomplish, since the USB bus is a Plug 'n play thing. One of the first things the master has to do is to enumerate the devices that are on the bus, and it has to do it dynamically, since a device can be added at any time. Then it has to manage the configuration of the device (if needed) and then set up the comunication. Things gets soon very complicated even for a simple comunication with a mass storage. In this case, after the USB 'low level' protocol, you will have to deal also with the "Mass storage" layer.
All I remember is that on the Microchip knowledge base there was some application note with a very simple implementation of basic usb protocol master made to be run on a their smallest microcontrollers, but i regret to say that I don't have any link to it anymore.
Whatever you do, it will be a huge work, and probably lot of fun . Good luck !
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If the idea of the project is to prove that you can do it on that aged CPU, just for fun, I guess you'll have to do the big work of implementing a USB host.
If you have a problem that requires a solution, one way or the other, you could use one of the tinier Arduions as a relay: Your old CPU talk through an RS232 interface to an Arduino that acts as a USB host through e.g. The Arduino USB Host Shield[^], forwarding the data to the USB devices. Making the two boards cooperate is a nice challenge as well: You will have to do some protocol development to synchronize activities under two quite different OSes. Not too hard, but well above what you would give as a homework assignment to a freshman CS student.
I am sure that there are similar Raspberry Pi solutions, but Pi solutions tend to be more ambitious, larger, more expensive. Arduino solutions are often more limited, but much simpler to handle if all you need is a very simple solution.
If you are a soldering iron person: That Arduino web page refers to the MAX3421E[^] chip on the shield. You may of course try to get hold of one of those and add to your setup, avoiding the complexities of an Arduino. You can probably pick up a lot of useful info from the Documentation tab on the Arduino page (such as the diagram for the shield).
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