Oric Projects and Repair.

INTRO. This page has some of the hardware projects that I wrote for Rhetoric.
I'm also adding some of the hardware information I have acquired over the years.

Please note ... I will not accept any responsibility for any damage resulting from the information on these pages, or for any mistakes that may result in harm to you or your Oric. I have checked as best I can but use of any of this information is at your own risk !!!

I've recently discoverd that one of the Cumana disk interface sheets I have is actually an Oric disk interface circuit diagram. The reason I didn't notice is it is almost identical.
(Previous entry) I've found another sheet of info showing the other side of the Microdisc board. I've not been able to find out which version of the Microdisc this is from but I'm told there are different ones.

CUMANA circuit diagram. I've rescanned this so hopefully it is a little clearer.


French translation of the Service Manual Romu has done a great job of translating the Service Manual into French for the Oric community and the CEO have added some extra information, including a better scan of the circuit diagram. To help download this I've split the file into these two parts.
Manuel Technique is the manual and Complément is the additional supplement.

Many thanks to Romuald Line and the CEO for their efforts !

Microdisc Circuit diagram and component details ***UPDATED***.
I get asked from time to time if I have any details about what the Microdisc interface is like. Here is the info I have. The images are monochrome .GIF files which is supposed to be better but if you want .JPG versions email me.

Right click this link and Save Target As... for Oric Microdisc Manual

The Service Manual for the Oric-1 and Atmos Computers.
Probably the rarest Oric book. I've only ever seen one which I bought from
www.instruction-manuals.co.uk and scanned as I know how useful this can be. I'm very concerned about people using this information. It tells you how to repair your Oric - but how good are you at repairing double sided PCBs ? Please get a competent electronic engineer to make modifications for you. Don't kill your Oric !
There is some stuff here that you may find interesting even if you aren't trying to fix a broken Oric. The book seems to be a draught version. For instance, it contains a sentence that isn't finished and there is not information filled in on page 2. I don't know who the author was or if there are any other versions in existance. As I said this is the only one I've ever seen or heard about. that must make it a fairly important find - but the real worth is the information contained in the document. Use it well !

Oric circuit diagram images. You'll need these for several projects and certainly for repair work. If you need a hard copy I still have several available, otherwise print a copy from the link provided.

Serial Port Circuit diagram. Sorry this is a bit of a poor image ! For those that wanted to connect a modem, for instance, this could be useful. My modem came with a RS232 attached.

PSU Repair document. A Rhetoric article now missing it's pictures. I hope to retrieve these or redo them at some point. you should manage from the description.

Twin ROM & Audio Project. Somehow this didn't get printed in the last Rhetoric as intended. It details how to add a second ROM so that your Atmos can be an Oric-1 too. Also how to add a headphone or extension speaker socket with a handy volume control and switch to turn off external sound, (leaving sound to the headphones).

THE FILES. There are several different formats used here If you have any problems, send me an email and I'll try a different format .

New Oric disk interface circuit diagram Part 1   (91 Kb)
New Oric disk interface circuit diagram Part 2  (105 kb)
Oric Microdisc circuit details pdf file  (398 Kb)
CUMANA circuit diagram Part 1   (91 Kb)
CUMANA circuit diagram Part 2  (105 kb)
The Oric Microdisc and OricDOS manual pdf file
Oric Service Manual pdf file
Manuel Technique (Service Manual in French) pdf file
Complément (Service Manual supplement in French)
pdf file
Oric-1 and Atmos circuit diagram.Part 1 and make sure you have Part 2
Serial Port diagram. jpeg image
PSU Repair MSWord document or pdf file with pictures
Twin ROM project Project part 1 Sound project Project part 2

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