I have seen a SD card to floppy adapter before. https://en.m.wikipedia.org/wiki/FlashPath
One of the most niche things I have seen in person. On Wed, Nov 1, 2023, 8:37 AM Ted Mittelstaedt <t...@portlandia-it.com> wrote: > It's not QUITE this bad but it is pretty bad. > > I use USB external hard disk docs and disks for backup. Once you get a > COMPATIBLE device then backup over USB is reliable. > > But there are many dock models out there that won't work with different > motherboards or will work a few times then stop working. > > And it's the same thing whether you are running Linux or Windows on the > systems. > > I have also tried using USB-to-serial dongles for industrial control of > PLCs and such, it did not work. The dongles will drop characters and the > market is full of counterfeit dongles anyway. The rs232 port pcie cards > generally work. > > Ted > > -----Original Message----- > From: PLUG <plug-boun...@lists.pdxlinux.org> On Behalf Of Ben Koenig > Sent: Friday, October 27, 2023 12:46 PM > To: Portland Linux/Unix Group <plug@lists.pdxlinux.org> > Subject: Re: [PLUG] Simultaneously horrifying and amazing! > > > ------- Original Message ------- > On Friday, October 27th, 2023 at 10:20 AM, Bill Barry <b...@billbarry.org> > wrote: > > > > On Fri, Oct 27, 2023 at 12:15 PM Russell Senior > > russ...@personaltelco.net > > > > wrote: > > > > > It wasn't the RS-232 that surprised me, it was the combination of > > > RS-232 and PCI-E, when I expected that modern RS-232 interfaces to > > > just use a USB converter. It is kind of like finding someone putting > > > a Pratt and Whitney turbo fan on a Sopwith Camel. > > > > > > And here I was just about to reply and ask what would be the > > > advantage of > > > > a PCI-E card over the much cheaper USB converters :) > > > > Bill > > USB is designed as a user-friendly Plug 'n Play connection. There is a lot > of variety in how it is implemented and it tends to do weird things when > used for long term connectivity. > > I encountered this in the storage world. People who use USB for backup > storage typically leave the external HDD connected indefinitely, which > eventually causes problems. At some point the USB host controller will > reset the port. There are also issues with power management where host > controllers will put a port to "sleep" and issues with the amount of power > delivered to the port not being consistent. > > PCIe on the other hand, is a much more robust interface. Once you plug it > in and power it on, it stays that way until the rapture. Less variance in > how vendors implement it. > > In Linux, the USB host controller drivers include a system of "quirks" > which are enabled/disabled based on the make/model of the chip. For > example, here's a bit of code from the latest stable kernel where they > describe enabling one of these quirks for Intel hosts. > > <code> > /* Existing Intel xHCI controllers require a delay of 1 mS, > * after setting the CMD_RESET bit, and before accessing any > * HC registers. This allows the HC to complete the > * reset operation and be ready for HC register access. > * Without this delay, the subsequent HC register access, > * may result in a system hang very rarely. > */ > if (xhci->quirks & XHCI_INTEL_HOST) > udelay(1000); > </code> > > Note how this specifically calls out Intel. As if other vendors don't > implement this same 1ms delay? > -Ben > >
