Pi lightweight server with USB SSD instead of powered HDD?

Nope, MB. Big enough for a firmware image (probably its intended use) and a small handful of gcode files, and that's about it. I'm looking at one right now, and it says "128MB:"

At least there's no danger of it being counterfeit. Who'd bother? :)

_/_ / v \ Scott Alfter (remove the obvious to send mail) (IIGS(

Maybe a 1GB chip because they couldn't find anything smaller to fill the order for 128MB cards.

My first computer was an Elliott 503 - Three (IIRC) wardrobe-sized and shaped grey boxes plus a control desk. It was big because it was built using discrete transistors. It used 39 bit words in an 8Kword ferrite- core memory. Each work could hold 2 19 bit instructions. If the 19th bit was zero the instructions were separate: if it was set, the first instruction modified the second and ran at 6,7 MHz clock speed. It was designed as a scientific and engineering machine and managed to be a few percent faster at floating point calculation than it was at integer arithmetic. It had another 16Kwords of ferrite core that was used essentially as a very fast disk: it could be used as workspace for array operations and the Algol compiler, assembler and other support programs were loaded from it. Apart from that, its only I/O was a fast lineprinter, two paper tape readers and two paper tape punches. I learnt to program in Algol 60 on it during my last year at university.

The Elliott 803s at National Museum Of Computing were binary compatible with with the 503, but about 70 times slower. However, if you want to see something REALLY slow, visit the NMOC and see the Harwell Dekatron in action! It uses relay-based logic, Nixie tubes for memory and paper tape i/o.

But I digress, what I came here to say was that after University, I joined ICL and learnt PLAN assembler on a 1901 (punched card reader, lineprinter and 4 x 1/2"mag tape drives plus the operator's control teletype). That was quite slow: if the file you wanted was on tape deck

When off the drive, each disk lived in a clear plastic cover which included the handle used to lock it onto the drive and with a cover that screwed onto the bottom to keep dust out.

Which brings me to the point of this rigmarole: one day we were doing some last minute testing, so there were 2 or 3 of us rushing round the machine room and operating the machine to complete testing , when Gary, the programming manager, realised that the wrong disk for what we were doing was on the drive, so he rushed over to the disk cabinet, put that drive into its drawer, grabbed the one we needed and set off at a gallop for the drive. He'd forgotten one thing: the thread holding the bottom case on that drive was stripped and fell off in mid-gallop, hitting the floor with a clatter. He immediately thought "Crap: I've dropped the bloody disk!" - and let go the handle. Then, realising what he'd done, managed to grab the drive by its handle before it hit the floor, and managed to put it on the drive before tottering off to recover: unsurprisingly, He wasn't a lot of use for the rest of the day. Just as well he made the save since we had neither a spare disk nor a backup for the one he almost smashed.

Yeah; when you drop a hard disk you get bits all over the place :-)

My first computer, a Transam Wren, came with 2 5.25" floppy drives and 16 KB (yes, kilobytes) of RAM. I decided I could afford the upgrade to 128 ( or was it 256) KB RAM, but the cost of the upgrade to a 5 MB hard drive was beyond me. That was in 1981 - I remember driving to Gray's Inn Road in London to collect it, a few weeks after I'd passed my test.

What capacity were the large removable multi-platter discs (in a transparent plastic case with a twist handle) that were used in mainframe computers of the 1970s? My first sight of a computer was in the machine hall at ICL's BRA01 (Bracknell) site, when I was on a BASIC course for schoolchildren in

Even when I started work in 1986, the computers still used open-reel tapes (as opposed to QIC cartridges). But I think all the discs were fixed, not with removable platters.

On the 1900 series the first drives, which I never saw, were 4MB (more strictly, 4 MCH, since, as you my remember 1900s used a 24 bit word which cound be subdivided into 4 6-bit characters.

The first 1900 I saw, with disks, had one 8 MB drive. After a couple of years we swapped that for a 1903S (32Kword memory, 2 EDS60 60MCH disks (20 14" platters), same physical cabinet and method of mounting removable disks. We ran George 3 on that.

The 2903, a desk-size orange box that ran in a standard office environment, used a single platter 5 MCH disk, but could also use the EDS60 drives (in separate cabinets and rather on its limits at usual office temperatures. The 2903 was actually a 2900 DFC (Disk File Controller), in a different box and running George 1* on top of a 1900 emulator, so it could run standard 1900 software.

Wen the 2900s were rolled out, they got EDS100, EDS200 and EDS640 disks, respectively 100, 200, 640 MB capacity, but same 14" platters, only a lot more of them.

Same here. The only tape I've used at work was 1/2" (7 or 9 track, 10" or

At one point I was using 4 GB DAT cartridges for backups at home, but it was relatively slow, especially compared with any USB-connected HDD. So, now my backups are all done using USB-connected portable 2.5" drives and using rsync and rsnapshot as the backup software.

I still have the tape drive, ISA interface and some tapes: must do something useful with them, such as giving them to NMOC.

If a non-programmer looked into the machine room while a CE had his head in a disk drive well, cleaning and aligning heads, I would explain (with as much of a straight face as possible) that it was important that the pack not spin too fast because it would make the bits fly off the disk - and that the CE was scraping those stray bits off the inside of the drive.

The most common example was the packs used on IBM 2314 drives or clones. They officially could hold 29.17 megabytes, but that was a theoretical maximum which was never achieved in practice. A more realistic figure was 20 to 25 megabytes.

The 2314's predecessor, the 2311, had a shorter stack (10 tracks per cylinder), with an "official" capacity of 7.25 megabytes.

The successor, the 3330, held 100 megabytes on a pack (200 megabytes on later models).

NY wrote on 7/16/21 3:30 PM: [...]

on my pi4 I have 1 240GB ssd and a 4TB disc the disc is powered by it's supply adapter, the ssd is not,still drew too muchpower, so Ihad to find a powered usb hub which is powered but doesn't "backpower" the the pi...... the second one I've bought worked....

-rasp

On Fri, 16 Jul 2021 21:46:59 +0100, "NY" declaimed the following:

Presume we speak of personally owned vs those we'd had access to (like my college Xerox Sigma-6).

Mine was a TRS-80 Model III; initially 32kB RAM using a cassette deck. It took a year before I could justify the cost of having the floppy disk controller and 1 drive installed -- nice thing was Radio Shack dropped the price of that package, and of RAM, while it was still in their shop, so I was able to argue for the lower price with the price difference going to "fully populate" the RAM (48kB -- ROM BASIC filled the first 16kB).

It wasn't for a few more years, after upgrading the system to a Model 4 mother board (which meant I still had the original power supply -- which was bigger than factory Mod-4s) that I could upgrade to 128kB of RAM (still had the 16kB ROM as I recall, but booting from a floppy did a bank swap of the first 16kB). The extra 64kB was only accessible as bank swapped 32kB with the upper RAM region, or via some I/O scheme (used by Multiplan as I recall).

The 5MB hard drive was $5000 when introduced... Which was more than the computer even with all the upgrades I'd done. Think the floppies and RAM added only around $1000 on top of the $1500 or so for the Mod-III, and the Mod-4 upgrade was another $1200 or so.

For some reason my mind recalls the college machine as having 100MB drives -- something like six of them. It was a big deal the year we got two

Even a 100MB drive was huge for the era (11 platter, the top and bottom sides were not used, so equivalent to 10 surfaces per track).

Insufficient power from *where*?

The Pi does not *supply* the power - the power supply supplies the power.

Just use a beefier power supply to the Pi in the first place.

Apparently this is only true for the A+ and Zero (I didn't know this). On other RPi's from B+ onwards, the current is limited to 1.2 A for all USB ports together, no matter how beefy the power supply:

Yes, but if your power supply can't provide enough juice to run both the Pi AND the USB ports, a "bigger" PSU will help.

Oh, right, yes. I had assumed that was a step already taken. At least it is for the "official power supply" which I always used from the Pi 3 onwards after the slightly cheaper ones I used for the Pi 2 gave me trouble on the Pi 3.

At work we used open reel (first job), QIC and later Exabyte or DAT (I forget which).

At home I started off doing backups to Zip disks (100 MB), then to CD-RW (650 MB) and now to USB-connected HDDs. I try to keep the HDDs in a firesafe in the garage when not in use, but it's a nuisance to have to go out to the garage whenever I want to update a backup, so I tend to keep the common stuff (documents, emails, TV recordings) on drives that live at the other end of the house from my study - so maybe they will survive if a fire or theft causes me to lose the PC drives.

There isn't much stored on the Pi discs (TV programmes get recorded there but then moved to the Windows PC for watching and/or permanent storage). The only stuff is weather station data, and I back that up over the network by sharing the directory using SAMBA and then copying from there to the backup drive via the Windows PC, along with document/email backups.

I understand it, though it takes longer to describe than to do ;-)

As an aside, I spent a lot of time in a team at ICL which ported what was effectively SAMBA onto ICL servers and network protocols. We sold it to various customers. Now that functionality (minus the domain-control stuff *) is available for free as a downloadable package on any Linux.

(*) Domain and permission stuff bored me: I'm more turned on by making things possible, rather than by making things impossible for unauthorised people. Security is essential - but boring ;-)

You've got me wondering now whether 256 KB was a realistic figure. I *think* it was either 128 or 256, upgraded from the base RAM of 16 KB.

I was half right:

The manufacturing date is given as 1984. I *think* I had it right from the beginning of my time at university (1982), having bought it a year earlier. Again, my memory may be playing tricks.

It was a Z80-based motherboard, running CP/M3. It also had BBC Basic (ported from 6502 on BBC Micro, presumably). I made a few little add-ons like an ADC board and a DAC board (for converting analogue to digital and back again) which interfaced with the Winchester port (effectively a Centronic parallel interface), and an RGB to PAL board (using a 4.43 MHz crystal and a PAL encoder IC) so I could drive a TV to see the screen output in colour rather than shades of amber - with all the smearing and colour fringes that you get with PAL!

My understanding was that the Pi does some voltage conversion or stabilisation, and that simply adding a 5V PSU that is capable of supplying more current/power to the Pi doesn't allow more power-hungry devices to be connected to the Pi's USB ports.

Certainly I saw the CPU temperature (as reported by the taskbar widget) rise when I plugged in an HDD, which suggests that the input power rail from the PSU is not electrically connected to the output power rail of the USB port, but that circuitry on the Pi motherboard is place "in between".

Yes, I'm using the official Pi PSU for the appropriate Pi.

The Natural Philosopher wrote on 7/17/21 7:08 AM:

only it might not work, because:

of course you could stick 5V up the POE jumper,or use a "stupid" usb C cable,,,,

-rasp