INSERT SYSTEM DISC... ORIC MICRODISC NEARLY THERE

Yo, fans of the Oric Microdisc and it's associated power supply brick - yes, I'm talking to approx 0.05% of the retro micro fan base population out there but no matter.

I've currently got three words for you and they are:

INSERT SYSTEM DISC



You may recall Graham took my long-suffering Oric Microdisc unit and gave it a little TLC in terms of the drive mechanism getting a clean but the main thrust of his work was to completely overhaul and modernise the power supply as it had long been suspect in terms of providing stable voltage - in fact, all the drive would ever do is work for a short while, when it felt like it, and then pack-up due to overheating. In other words, it had become nothing more than a paperweight.

I have only been able to give the microdisc 20 mins today as we've had family visits and the removal of a washing machine and 3 kitchen units as the builders are due to begin the next phase of the works here tomorrow as they enter with their nice looking sledgehammer and rearrange our downstairs toilet and pantry area. Our loss is our mate's (Fast Eddie's) gain as he today took ownership of a virtually brand new Samsung washing m/c which unfortunately is slightly too large to become part of our integrated new units... c'est la vie, but basically life is always full on around here and you never get a moment for hobbies right now and I'm sure it's the same for some of you guys - there's always summat needs doing/shifting/mending/feeding/working on, right?

Hopefully, I'll get the lid off the disc drive one night this week and just have a look-see if any cable has perhaps come loose internally or maybe I need to check a DIP switch or something because no matter which 3" Oric DOS/Sedoric disk I try inserting in the mother, how many times I reset the button on the back, the Oric still screams out...

INSERT SYSTEM DISC

Graham, I am 99.9% (as much as anyone can be) certain that once we get a disk booted-up, I will suddenly have a reliable Oric 3" Microdisc system (thanks to you sorting out and rejuvenating the PSU) which would be marvellous as these units are pretty hard to get hold of and of course means my system retains 100% originality which is always nice.

But, if the worst comes to the worst (and really how can anything like this be considered in any way 'bad' when we lurve our little mods etc), as you've pointed out, I can always gut the existing 3" drive unit and bang in an SD card/HXc/Cumulus type solution so as they commonly say, everyone's a winner and I'm chuffed to bits with progress as this little gal is now nearly there...


ABOVE: UPSTAIRS AT BAZ's... the Oric collection is looking good.


ABOVE: Graham's packing is 1st class - all sealed/double wrapped and secured as snug as a bug in a rug.


ABOVE: The stable, modernised and much-improved PSU now has a power LED to show it's on.


ABOVE: No matter how many disks I tried, the Oric was still adamant that I...

INSERT SYSTEM DISC

No worries - I sense it just needs a tweak, a look under the bonnet - a minor detail somewhere...



Once more, many thanks go to Graham for a thoroughly fine job and if any Orician still alive/awake has a suggestion as to where I should specifically look, then of course old Baz is "all ears".

Cheers once again, Graham and I'm sure we'll have a few more updates for you in this thread soon...

 

Hmm well that's a bit disappointing Andy. I guess the power is good, and the interface I'm guessing is working o.k as it recognises it has a disk drive system.
I wonder if I left the drive unplugged from the interface inside I wouldn't have thought so, likewise any of the connectors.
or dip switches (don't remember seeing any) Is the Drive motor spinning I ask as most of it is using the 5V line, the floppy drive uses 12V as well for the main servo motor driving the disk around. (P.S you did get further than me with no Oric to attach it to)
I'm going to check through the pictures I took when putting it back together.
Just thought the drive was spinning seemingly waiting for a disk to be inserted.

 

I've looked through the pictures all looks well i.e. plugged in, the drive it self does have dip switches, but unless by accident wouldn't have moved them.
Sorry its not just burst into life

 

Hi, Graham.

Hey, it's no major surprise that the little bugger is still playing me up as it always did, mate!

Yes, the drive does spin the disk when it's inserted so you just get the feeling that there's a setting somewhere internally (a bit like on the back of a 1050 with the drive select switch?) that perhaps just needs a tweak?

As I say, we've a lot about to happen here when the existing kitchen gets blitzed but I will get another look-see at some point one night this week and send some more pics at the areas where I need to double-check DIP switch settings/cables/ connections etc.

Cheers once more, Graham and there's no way you could check this 100% as you were without an Oric to check with (plus, and here's the rub, some Orics work fine with a disk drive... other's... DON'T! Something to do with boards/revision issues, I believe...)

Never mind, onwards and upwards and we all like a little challenge ;-)

 

Thanks Andy I guess your right but that dosnt stop me being dissapointed and that's for both of us, lets hope I've nudged a dipswitch across or similar.
Remember I did disect the drive itself, so the connectors at CN5, CN3, and the one under the cable by the dipswitches (CN4 ?)have been disconnected. Also two on the underside of the board their near CN3 but on the other side CN1 & CN2
I did however take pics at the time as I disassembled, and followed them when putting back after cleaning the head properly (and yes had some brown goo on it, smoking maybe, could have been dust off the disk surfaces but more of a gum.)

 

I appreciate your pointers there, Graham, and the shared sense of "wouldn't it have been great if it had burst into life first time of asking" but life's often like that and we have to take the rough with the smooth and anyhow, it will feel an even bigger achievement if we do get it going in the end as it hasn't worked properly for so long I've never known it ever work reliably!

To keep us all ticking over, here's Oriclopedia and Dbug's look at a working system:

 

I'll have to postpone that until tomorrow, as it fairly long, and I love my F1 and been champing at the bit to watch it, (Pam hates it)

 

I'm the same as Pam, mate - I like disk drives going round and round but don't have any time for F1 drivers doing likewise(!!) Enjoy, pal - each to their own!

 

It might need VR1 adjusting on the Microdisc PCB that is often a cause of this symptom.

 

Nice one, Rich... you know what I'm gonna say next, don't you??!!

What if I send you the gubbins to have a look/see...LOL!

What I'll do, not tonight or tomorrow as we've stuff on taking surviving kitchen units to Fast Eddie's and I'm meeting up with an old pal tomorrow night out on the coast, is have a look under the bonnet and see if it's anything obvious. If it isn't then I will defer opinion to the experts on here and might well send it to you Richie as you have an Oric, yes? I might even have an Oric repair job on for you if you fancy an Oric-1 with a crapped out display on boot-up (ULA? RAM?) then we can adjust that Dragon sale to just about quits if you're up for that?

Anyhow, more to follow when I've had time to investigate the mysteries of the Microdisk...

Once more, thanks for all your pointers, hints and tips, lads.

If all else fails, I can always bang it in a cement mixer(!)

 

Nice one Andy, I’ll take a look at the Oric and the Microdisk as well if you want. I have an Oric-1 and Atmos to test the Microdisk as I adjust the VR1 ( depending on it’s current setting ).
Just send me a message when you plan to send it.

 

Many thanks, Rich.
That's brilliant of you that you'd be willing as I don't think we're far off with the drive thanks to Graham's maintenance job and PSU refurb, so I'll update you on here/via a text/email etc during the week.

Thanks again to Graham for sending the PCB of the drive (they look like DIP switches over to the far right, near the edge connector) and Vyper Rich for the circuit diagrams.

 

Nice one Richie
Just tried to work out what VR1 actually does, seems like a delay circuit of sometype going in or possiably out of and unidentified chip. i.e adjust current flow through Capacitor C13
P.S did you see the Blog with pics of the guts of my IBM XT ?

 

Hi Graham, not yet but will do now. Here is the schematic for a Cumana board which does have a very similar layout and shows the LS221 and VR1.



all pictures in one frame online

 

Hey Graham how is your French?

https://drive.google.com/file/d/146g1NvuJDJooq9cmeOg5iVGgttFxd8Jc/view?usp=sharing

 

Crap for talking, o.k ish for reading but then there is my friend google translate.
Be nice if we can find the first two parts with the circuit board,schmatic, and GAL files it mentions.
was this published in an ORIC computer magazine ?

 

Also found these I'd stored on my NAS drive
I'm not sure but I think the diagrams are a little clearer than some I've seen, I can see pins 14 &15 on the LS221 with the cap and variable resistor much easier on these.

this one has some notes as well

Oh and slight change of direction , found this lot tucked away a bunch of 68B09's among them, shame there not CMOS 68C09'S

 

Sounds like you fellas are going through all your spares departments and Oric disk drive blueprints for which I'm very grateful. I am trying to find some screwdrivers this end small enough to tackle the Microdisc but when you take into account the rubble and disarray (everything packed away and don't know where 95% is anymore), bear with me, lads... it might prove mission impossible but if I can get into the case and do a little fault-finding / check the obvious, then I will...



ABOVE: Scene tonight in the Baz Cave - OK, Ground Zero.

 

Oh My ... " I only said blow the doors off... "
Hey Andy
do what I had to do... go buy another (screwdriver)

 

If you want Andy due to the space constraints just bypass that and send it up with the Oric.

 

Richie, the more I look (and have to tread through) the mess in our house, the more it looks like the best idea is to pack the lot up, upstairs here, and send it out to you.
I also have a nice couple of extra Dragon freebies for you which were in a parcel which sadly I never got round to opening that had been sat here the past 4-5 weeks!
You know what they say, fellas, my loss is Vyper's gain...
I'll pack the whole ruddy lot up over the weekend (if I can't get into the microdisc drive).
I will also update the thread in the next 48hrs.
Cheers again, Richie and Graham, for all your input and practical help on this one.
I really can't wait to get the old gal working at long last.

 

Andy, I've a cheap Gotek, I've not done the mods to add the oled, etc. would you like me to send that along with a 720K 3.5" drive for Richie to play with as well?
I'm guessing the interface must be working o.k as the Boot Rom knows it has an attached drive ? your call, and happy to upgrade to full on GOTEK.. we are talking cheap as in about £20 for the gotek as is OPlus I'll add the otherbits at a later date, (or send them to Richie to do.
Let me know

 

Hi Graham, thanks for the offer but I already have a couple of Goteks and some 720KB 3.5 drives. To test I may use my CPC’s 3” drive if I can sort the wiring out, but I should be okay.
Unless we are fitting a Gotek/3.5” Drive in place of the 3”unit.

 

Hi Richie
That's o.k then I wasn't sure what you had to test with, I hoped a Microdrive so swapping drives will confirm one way or another, but was thinking of alternatives drives, I suspect the drive or as you pointed out it could just be adjustment, however I think it used to 'read' or boot o.k but problems with formatting or writing to the disks, let me know what you think in regard the regulators I've fitted as well, be nice for a second opinion on them.

 

Hi, Graham and Richie.
First up, thanks Graham for that amazingly generous offer of a Gotek.
I will definitely consider it and make it the numero uno option if Richie can't get a peep out of the microdisc but I have a sneaking feeling that he might...
I've lifted the lid on the bugger today (after a really busy weekend) as we had Bev's folks down to inspect the ruins, my folks down for some pub grub (might as well, if Boris is paying) and had to get some ceramic kitchen tiles ordered as it won't be long before the builders'll be actually making things here all good after knocking ten bells of sh*t out of it as they are at the mo. Righto... what happened earlier today, after Bev magically found my sonic screwdrivers - I'd looked for days and found nowt except Rice Crispies and tea towels...she looked for 2mins and found em straightaway - how do women manage this trick??