Hi there!
I’m proud to announce the third 986-Studio project: The Replic’Oric!
But first, what is Replic’Oric?
Replic’Oric is an Oric Replica that will be done in two step, or version and this project have a few goals:
- The first goal is to provide a fully useable Oric Schematics as the only know schematics is an old scan from originals paper from Oric International and some part are barely readable or some components does tell their part number. (I.E. IC21 which is a 74LS04)
- The schematics will also include all known official reworks found in the service manual and on Oric from Oric France (buffer on Phi2, Diodes on tape signals.., +5V for SCART connector)
- The second goal is to provide replacement PCB for broken Oric. Thoses PCB will of course have a similar layout of the official one, especially on the connectors position, but I will try to keep major components positions and orientation
And there will be at least two version for the replica:
- The first version will be a fully vanilla one is to get a standard replica where all original components could be soldered and get a fully functional Oric.
- The second version will be a more “modern” version of the Oric removing the need of the ULA and most of the TTL chips and use a CPLD (or FPGA) to replace them, the 6502, VIA, PSG will of course be the same. This version will of course keep all the standard connectors, and may why not include all the StratoCumulus enhancement.
The roadmap is as follow for the first version:
- End of the 17/03 week: The schematics should be finished followed by a verification that everything is OK and the “new” schematic will be released
- End of May, the PCB layout should be done => release of the PCB layout
- June-July: A batch of PCB could be done (10 pieces will cost around $10/PCB, 30 pieces will be around $7, VAT and delivery excluded)
- End of this year: Depending on the difficulty of sourcing components, fully functional replica PCB could be made and sold (price unknown as it will really depends on components prices)
One problem on the “fully functional replica” is provisioning in ULA. But the more problematic is the ROM as there is still copyright on it. I may need to deliver without ROM or a Free one that will not be an Oric ROM. Or try to get official authorisation to distribute physical copy of the Oric 1/Atmos ROM (Bill G. where are you? 😉 )
The ULA problem could be solved by an ULA replica in a CPLD with an adaptation board to fit in a DIL40.
At the same time, the StratoCumulus project will also be done in parallel, but the roadmap is still unclear for now, so I can’t comment on it (and it will depends on other non Oric projects) And depending on what the Second version of the Replic’Oric will include, it may need to wait for the StratoCumulus.
Another part, is on the mechanical part. I’m absolutely not an expert on this, and the most complex part will be the Keyboard, I think it’s almost impossible now to build a copy of the Oric keyboard, and plastic mould cost really a lot and I don’t know what’s happen to Tangerine mould but I suspect they were trashed.. I really don’t know if making a replica case could be possible in the current situation.
So that is the brief of the Replic’Oric project.
Since I posted these informations on the Defence Force forum, I had finish the schematics and start working on the PCB layout.
The Schematics revision follow the official Oric Product International issue numbers tha latest issued board was Issue 4, I used a hand drawn schematics that was newer than issue 4, I give it the number 5, then I integrate the Oric International (Oric France) changes that are these one:
- add a transistor (TR4) on the 6502 output of Phi2 to try to have the cleanest possible Phi2 on the expansion board. I made this change optional as a jumper like LK3 (LK4 in this case) that will bypass the Transistor, so it should only be shunted without TR4 mounted.
- Two diodes are put on the Tape_in circuitry to try to prevent some loading errors.
- and the most important one 😉 I change the RGB out DIN 5 to a DIN 8 that is compatible with the normal 5 part and will add a +5V on the venter pin like Oric France did at that time.
This was for Issue 6.
Two days ago I was discussion with a friend (_DBug_) about what I can add on the 2 new pins on the DIN_8 RGB. I thought about adding the audio out (yes it could seem stupid as the tape port already have audio out.. But most of the tape cable does not have a audio out so that more or less useless.
So we were speaking about the VSYNC Hack, and during the discution it became evident that would be a great thing to add!
So I’ve made the Issue 6.1 schematics yesterday and here is what the dot one version will include:
- Audio out one the din connector and sync_in
- Sync_in is routed again through IC22 to be sure to have the best possible signal, then shared as the TAPE_IN like the original VSYNC hack was done.
This is currently under developement and the schematics will be released when it will be done 🙂
ORIC-1 ULA onto CPLD ??
I’m wanting to put an ‘Enhanced’ ORIC-1 ULA onto a CPLD , probably a EPM7512 or similar. My question :>>> is there VHDL / verilog code out there for the ORIC ULA ?? As this would make things much easier.
Thanks
Not sure what you want to do with an “enhanced ULA” but for a complete drop in, there is not much you can do. Adding more functionality would need changes on the PCB, You can’t with the Oric PCB output more color for example, you will need to do changes on the ULA to RGB port for that, and also probably disconnect all the composite part or some issue may rise.
And even the ULA is a fairly simple device, if you want to do major changes that would be changing virtually the whole thing, so I really don’t think it is worth to start from that.
Anyway there is no such code publicly available for now as far as I know.
I currently have a pcb bought from a guy in Russia, the resistor packs rp1, rp2, rp3 what is the correct orientation and ic23 the pal prom Ic what goes in here.
Thank you for your time.
I can’t tell if that PCB is an exact copy of the original Oric or not. I don’t have an Oric at hand right now, but from memory they are pack with common point, so you should be able to determine the common pin for these resistor packs by checking which of the side is connected to VCC or ground depending on the pack (though I think they all are connected to VCC)
The common point is always on one of the side and should be pin 1