Re: [Ql-Users] the heat!
Norman Dunbar wrote, on 23/Aug/12 18:37 | Aug23: On 23/08/12 16:26, Tony Firshman wrote: I find mine *does* need an external power supply when running some keyboards. Yes, the two USB ports are poly-fused to 100mA each. Some keyboards and/or mice draw more so the fuses kick in and increase resistance (why am I telling you this?) reducing current. This causes the keyboards to act like a QL with a dicky membrane, and misses keys or start auto-repeating at a huge rate. I have a USB wireless keyboard and mouse for mine, a Perixx Periduo 707 Plus, and it too draws too much from the USB port. Plugged into the Benq monitor's powered hub, though, it works as good as it does on my work laptop - both show the same problems such as it hangs unless I leave it connected after power up, for about 30 seconds - or I can unplug and replug the wireless dongle to get it working fine again. The Apple keyboard for instance wouldn't work at all when Pi was run off my monitor usb. I know they say 700ma, but it can be a *lot* less than that. 700 mA is the minimum required for the Pi, but the USBs are limited to 100 mA each. ... and the Pi to 750 ma. The codes on the poly fuses are: PSU - T075 USB - T014 ie 750ma and 140ma respectively. Tony -- t...@firshman.co.uk http://firshman.co.uk Voice: +44(0)1442-828254 Fax: +44(0)1442-828255 Skype: tonyfirshman TF Services, 29 Longfield Road, TRING, Herts, HP23 4DG ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
Tony Firshman wrote, on 26/Aug/12 12:12 | Aug26: Norman Dunbar wrote, on 23/Aug/12 18:37 | Aug23: On 23/08/12 16:26, Tony Firshman wrote: I find mine *does* need an external power supply when running some keyboards. Yes, the two USB ports are poly-fused to 100mA each. Some keyboards and/or mice draw more so the fuses kick in and increase resistance (why am I telling you this?) reducing current. This causes the keyboards to act like a QL with a dicky membrane, and misses keys or start auto-repeating at a huge rate. I have a USB wireless keyboard and mouse for mine, a Perixx Periduo 707 Plus, and it too draws too much from the USB port. Plugged into the Benq monitor's powered hub, though, it works as good as it does on my work laptop - both show the same problems such as it hangs unless I leave it connected after power up, for about 30 seconds - or I can unplug and replug the wireless dongle to get it working fine again. The Apple keyboard for instance wouldn't work at all when Pi was run off my monitor usb. I know they say 700ma, but it can be a *lot* less than that. 700 mA is the minimum required for the Pi, but the USBs are limited to 100 mA each. ... and the Pi to 750 ma. The codes on the poly fuses are: PSU - T075 USB - T014 ie 750ma and 140ma respectively. ... and I now see they are removed! https://www.element14.com/community/message/59032 I will jumper them on my board, and I expect my Apple keyboard will spring to life. Sounds a mite dodgy though, as people may add 500ma devices. The Pi does not have any other protection. Tony -- t...@firshman.co.uk http://firshman.co.uk Voice: +44(0)1442-828254 Fax: +44(0)1442-828255 Skype: tonyfirshman TF Services, 29 Longfield Road, TRING, Herts, HP23 4DG ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
Hi folks, summer is almost over and I'm still recovering from my Sinclair Microdrive Nightmare *1. Dilwyn Jones wrote: And if you plug a ZX Spectrum microdrive drive unit into the QL expansion port there were several problems: 1. It faced away from you with a standard microdrive ribbon cable. You had to fold and crease the short cable to make it face the right way. Earlier this summer I was playing with my ZX Microdrives to work with my QLs. See this PIC: https://skydrive.live.com/redir?resid=C250D8748980CE5A!4060 2. Spectrum microdrives would not format cartridges on a QL, though you could usually read and write OK. I think there was a bit of a speed difference IIRC, that Sinclair made changes to make QL drives work at higher capacity. Until late afternoon this Thursday I was unable to DIR, LOAD/SAVE/FORMAT using any of my ZX Microdrives with the QLs I've tried so far (4 ZX Microdrives with 4 QLs). See this PIC: https://skydrive.live.com/redir?resid=C250D8748980CE5A!4067 My first success was to use another ribbon cable. The one you'll see on the PICs seems to be bad as when trying to use it with the good working ZX Spectrum system, the Microdrive no longer works. 3. I never got to try this, but apparently if you strung six of those to the QL expansion port, the whole microdrive system would fail if you accessed MDV8_ - this is a feature of QDOS which Simon Goodwin documented in his rom bugs articles. Two more ZX Microdrives needed here to be able to verify this. *1 The Sinclair Microdrive Nightmare is a 13 episodes video production which was released in June/July 2012. Watch it on my YouTube channel (use link in the footer below). Cheers, Urs http://www.youtube.com/QLvsJaguar Sinclair, QL, ATARI, JAGUAR, NUON, APPLE more... Videos, pictures background information ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
oh! that would be depressing if it happened now, i'm wfh and i've just kicked off a full build. i totally forgot about power surges and brown outs, we lived in a converted maisonette back then with wiring going back to the fifties so even the neighbour's fan heater would freeze the computer. -- From: Norman Dunbar nor...@dunbar-it.co.uk Subject: Re: [Ql-Users] the heat! How about debugging DJToolkit way back when, by single stepping through my code and making sure everything was doing what it was expected to, and just as I was about to get to the stage where I suspected a bug was, the freezer started up and hung the whole system. That was irritating to say the least. Cheers, Norm. ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
thanks dilwyn no zx80, but i did have a zx81, i remember my and my sisters had competitions as to whom could keep their hands on it the longest. i had the microdrive problem, not consitently, but enough to break the flow. it was great when i finally saved enough to plug in some disks, i was totally in the future then :-) i didn't know about the chaisy dain issues. my goodness, how did we put up with it? if anything stops working at the office i start cursing at it within a few seconds. he he he. fern --- From: Dilwyn Jones dil...@evans1511.fsnet.co.uk Subject: Re: [Ql-Users] the heat! If you ever had a ZX80, that thing got even hotter than a QL. It was rumoured back then you could fry an egg on it, although I'm not sure anyone ever dared to try! Amazingly despite getting so hot it would usually keep working reasonably well. An annoying feature of my first QL was that microdrive cartridges which were recorded on MDV2_ would usually not work in MDV1_ (or vice versa). And if you plug a ZX Spectrum microdrive drive unit into the QL expansion port there were several problems: 1. It faced away from you with a standard microdrive ribbon cable. You had to fold and crease the short cable to make it face the right way. 2. Spectrum microdrives would not format cartridges on a QL, though you could usually read and write OK. I think there was a bit of a speed difference IIRC, that Sinclair made changes to make QL drives work at higher capacity. 3. I never got to try this, but apparently if you strung six of those to the QL expansion port, the whole microdrive system would fail if you accessed MDV8_ - this is a feature of QDOS which Simon Goodwin documented in his rom bugs articles. There we are Fern, some more nostalgia for you! Dilwyn Jones ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
any one got any tales of annoying little things which in retrospect are quite charming? How about debugging DJToolkit way back when, by single stepping through my code and making sure everything was doing what it was expected to, and just as I was about to get to the stage where I suspected a bug was, the freezer started up and hung the whole system. That was irritating to say the least. Cheers, Norm. -- Norman Dunbar Dunbar IT Consultants Ltd Registered address: Thorpe House 61 Richardshaw Lane Pudsey West Yorkshire United Kingdom LS28 7EL Company Number: 05132767 ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
On 24 Aug 2012, at 12:11, Norman Dunbar nor...@dunbar-it.co.uk wrote: any one got any tales of annoying little things which in retrospect are quite charming? How about debugging DJToolkit way back when, by single stepping through my code and making sure everything was doing what it was expected to, and just as I was about to get to the stage where I suspected a bug was, the freezer started up and hung the whole system. That was irritating to say the least. It was that sort of QL crash (washing machine in my case) that prompted me in 1985 to design Computer Cleaner. It worked so well I started selling it at the ZX Microfairs and was sucked into the QL trading business. I sold thousands of the things! That was well before anyone like Belkin was even heard of! Now Belkin and others sell flashy Chinese made ones that are mainly inferior, but far far too cheap to even consider competing with. I had very recently a very pretty looking Belkin one to repair for a friend. It had far fewer and smaller components than mine did in 1986, and didn't even have inductance. The neutral lead had broken off! Tony -- t...@firshman.co.ukhttp://firshman.co.uk Voice: +44 (0) 1442 828254 Fax: +44 (0) 1442 828255. Skype: tony firshman TF Services, 29 Longfield Road, Tring, Herts, HP23 4DG ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
Hi, another aspect of computing in the early eighties - not related to heat (even if it had some potential to heat up the atmosphere) - were the competing interests for the (sole) TV set in the house. Kids of today can't really understand that. Cheers, Tobias -Original-Nachricht- Von: fernando gonzalez ferng...@gmail.com An: ql-users@lists.q-v-d.com Betreff: [Ql-Users] the heat! Datum: Thu, 23 Aug 2012 15:56:11 +0200 hi all little reminiscence last week while we had rather more seasonal temperatures (ie it was warm), one of the most annoying aspects of computing in the 80s rapidly re-asserted itself: 1) QL would last about 15 minutes and then crash badly. 2) quickly check all the chips were seated properly. 3) wait 20 minutes for it to cool down 4) quickly rush to do the next bit of coding before it got too hot again. 5) back to step 3 i think i need to get a little noisy desk fan pointing at the heat sinks to complete the full 80s feel. any one got any tales of annoying little things which in retrospect are quite charming? cheers fern ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
Hi Tobias, On 23/08/12 15:22, tobias.froesc...@t-online.de wrote: Hi, another aspect of computing in the early eighties - not related to heat (even if it had some potential to heat up the atmosphere) - were the competing interests for the (sole) TV set in the house. Kids of today can't really understand that. They will. Just as soon as their Raspberry Pi arrives and they want to plug it into the TV! ;-) Cheers, Norm. -- Norman Dunbar Dunbar IT Consultants Ltd Registered address: Thorpe House 61 Richardshaw Lane Pudsey West Yorkshire United Kingdom LS28 7EL Company Number: 05132767 ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
Norman Dunbar wrote, on 23/Aug/12 15:37 | Aug23: Hi Tobias, On 23/08/12 15:22, tobias.froesc...@t-online.de wrote: Hi, another aspect of computing in the early eighties - not related to heat (even if it had some potential to heat up the atmosphere) - were the competing interests for the (sole) TV set in the house. Kids of today can't really understand that. They will. Just as soon as their Raspberry Pi arrives and they want to plug it into the TV! ;-) (8-)# I find mine *does* need an external power supply when running some keyboards. The Apple keyboard for instance wouldn't work at all when Pi was run off my monitor usb. I know they say 700ma, but it can be a *lot* less than that. I suspect a wireless keyboard (and mouse if really wanted) and the pi would quite happily run off a TV usb output. Tony -- t...@firshman.co.uk http://firshman.co.uk Voice: +44(0)1442-828254 Fax: +44(0)1442-828255 Skype: tonyfirshman TF Services, 29 Longfield Road, TRING, Herts, HP23 4DG ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
any one got any tales of annoying little things which in retrospect are quite charming? cheers fern If you ever had a ZX80, that thing got even hotter than a QL. It was rumoured back then you could fry an egg on it, although I'm not sure anyone ever dared to try! Amazingly despite getting so hot it would usually keep working reasonably well. An annoying feature of my first QL was that microdrive cartridges which were recorded on MDV2_ would usually not work in MDV1_ (or vice versa). And if you plug a ZX Spectrum microdrive drive unit into the QL expansion port there were several problems: 1. It faced away from you with a standard microdrive ribbon cable. You had to fold and crease the short cable to make it face the right way. 2. Spectrum microdrives would not format cartridges on a QL, though you could usually read and write OK. I think there was a bit of a speed difference IIRC, that Sinclair made changes to make QL drives work at higher capacity. 3. I never got to try this, but apparently if you strung six of those to the QL expansion port, the whole microdrive system would fail if you accessed MDV8_ - this is a feature of QDOS which Simon Goodwin documented in his rom bugs articles. There we are Fern, some more nostalgia for you! Dilwyn Jones ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
From: Dilwyn Jones 2. Spectrum microdrives would not format cartridges on a QL, though you could usually read and write OK. I think there was a bit of a speed difference IIRC, that Sinclair made changes to make QL drives work at higher capacity. I have discovered this, when I have built my first QL-T (sic!). I have used the potentiometer on the mdv's PCB and if it runs at a bit (!) higher speed , it has got more sectors after a FORMAT mdv1_. BTW: If you put a germanium diode in the MDV select pin, you can access both mdv1_ and mdv2_ with one drive Was very good in a small dektop case. Cheers...Ralf ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
On 23/08/12 16:26, Tony Firshman wrote: I find mine *does* need an external power supply when running some keyboards. Yes, the two USB ports are poly-fused to 100mA each. Some keyboards and/or mice draw more so the fuses kick in and increase resistance (why am I telling you this?) reducing current. This causes the keyboards to act like a QL with a dicky membrane, and misses keys or start auto-repeating at a huge rate. I have a USB wireless keyboard and mouse for mine, a Perixx Periduo 707 Plus, and it too draws too much from the USB port. Plugged into the Benq monitor's powered hub, though, it works as good as it does on my work laptop - both show the same problems such as it hangs unless I leave it connected after power up, for about 30 seconds - or I can unplug and replug the wireless dongle to get it working fine again. The Apple keyboard for instance wouldn't work at all when Pi was run off my monitor usb. I know they say 700ma, but it can be a *lot* less than that. 700 mA is the minimum required for the Pi, but the USBs are limited to 100 mA each. I suspect a wireless keyboard (and mouse if really wanted) and the pi would quite happily run off a TV usb output. There's a web page at http://www.elinux.org/RPi_VerifiedPeripherals which has a list of what works and what doesn't. Of course, I didn't find it until after I'd bought by keyboard! HTH My USB powered hub, separate from the monitor, seems to feed power back down the interconnect cable to the Pi. The Pi's power LED comes on when the hub has power and the Pi doesn't. :-( It also refuses to boot with the hub attached. It also kills the network when I connect the hub after booting the Pi. Guess what, I bought that before finding the above page as well! Sigh! Cheers, Norm. -- Norman Dunbar Dunbar IT Consultants Ltd Registered address: Thorpe House 61 Richardshaw Lane Pudsey West Yorkshire United Kingdom LS28 7EL Company Number: 05132767 ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
Norman Dunbar wrote, on 23/Aug/12 18:37 | Aug23: On 23/08/12 16:26, Tony Firshman wrote: I find mine *does* need an external power supply when running some keyboards. Yes, the two USB ports are poly-fused to 100mA each. Some keyboards and/or mice draw more so the fuses kick in and increase resistance (why am I telling you this?) reducing current. This causes the keyboards to act like a QL with a dicky membrane, and misses keys or start auto-repeating at a huge rate. Interesting. Yes I knew about the fuses, of course, but not the capacity. However my Apple keyboard is fine when Pi is run off a USB charger, but not off the monitor usb port. The issue must be the monitor power limit, not the polyfuse limit. Do these polyfuses degrade at all I wonder? Tony -- t...@firshman.co.uk http://firshman.co.uk Voice: +44(0)1442-828254 Fax: +44(0)1442-828255 Skype: tonyfirshman TF Services, 29 Longfield Road, TRING, Herts, HP23 4DG ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
From: Tony Firshman Ralf Reköndt wrote, on 23/Aug/12 18:18 | Aug23: BTW: If you put a germanium diode in the MDV select pin, you can access both mdv1_ and mdv2_ with one drive Was very good in a small dektop case. Fun if you try to copy form mdv1_ to mdv2_ (8-)# Tony -- Hehe ;-) no, never have tried this. I former tried to work out a digital way with a few NAND chips for doing that and was very surprisesed, that a single germanium diode hat done the work (after finding out, that my way didn't work). As usual, Sinclair made it easy ;-) Cheers...Ralf ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
Re: [Ql-Users] the heat!
Am 23.08.2012 um 18:58 schrieb Dilwyn Jones: any one got any tales of annoying little things which in retrospect are quite charming? cheers fern 1. It faced away from you with a standard microdrive ribbon cable. You had to fold and crease the short cable to make it face the right way. I used to have a leftover drive from my Spectrum and never used it on the QL because of that. I seem to recall my cables were too short to be twisted to have that d**n thing the proper way round. And, facing backwards, it looked embarrassingly amateurish. 2. Spectrum microdrives would not format cartridges on a QL, though you could usually read and write OK. I think there was a bit of a speed difference IIRC, that Sinclair made changes to make QL drives work at higher capacity. Don't remember that. I /think/ format worked with my drive. But, too long gone….. Tobias ___ QL-Users Mailing List http://www.q-v-d.demon.co.uk/smsqe.htm
