OMC-to-2560-Adapter update
Alex Gibson
Hi all
After a litany of delays, shipping mishaps and some customs wrangling on top of a global pandemic, I’m at last in possession of 10 nicely made PCBs of the OMC2560 design Bo and I worked on way back. The good news is it seems that now we have the correct boards, they’re all good quality and ready to go.
As you can see these closely match Al Wood (Folknology)’s original OMC in all ways, and are designed to be a plug-in replacement for the current ATMEGA644p processor, which can be gently levered out with a flat bladed screwdriver and stored in case you want to revert.
The spirit behind this upgrade is very much the same as the old ‘sideways RAM/ROM’ boards you could get for 80’s microcomputers like the BBC – so what if it wasn’t designed for an upgrade, if we can get at the pins, we can make it happen! The whole board ‘plugs in’ to the socket for the 644p and replaces it, and can be extra secured with standoffs to the main board.
This bring the OMC bang up to date – or at least as far as 8-bit machines are concerned, and we really don’t need 32-bit for anything we can do on a TVRR!
The primary purpose was to break free of the increasing limitations of the ATMEGA644p – to compile the latest Marlin firmware without having to disable essential functions like SD support.
The ATMEGA2560 is able to build recent Marlin with all desired features J We should be able to add things like auto bed levelling, power off resume, displays… all the toys.
I am delighted to confirm that OMC board support has survived into Marlin 2.0, and I’m working on a port of our firmware to this. Can’t guarantee success but we already did the last Marlin V1 which does everything.
With 3 DSM boards, the OMC was always capable of driving 3 extruders (or a total of 6 axes) – the only catch was that you could not control a heater and fan for each. This board adds up to 4 more MOSFETs to control extra fans etc. That might be overkill for you – we don’t have to populate them all!
We’ve added support for LCD displays – the standard RepRapDiscount Smart/Full Graphic controllers should work. There is a jumper to let you decide whether to use the SD card slot on the display or the original on the OMC.
- Getting it made:
I’ve sourced the components needed to make 1-2 boards, and am about ready to make the first one.
These are through-hole and simple to solder just like the original – with the obvious exception of the ATMEGA2560 which will be a fun/tricky SMT solder job!
How do people who have expressed interest feel about sourcing components, and assembly – in particular do people feel confident to tackle the 2560?
I could see 4 options –
1) I just get these boards to you ASAP, you source parts (I will share the BOM) – instant gratification but you need to duplicate work I need to do anyway
2) I source all the parts to make a kit including the 2560 – at cost. This is cheapest as I should save some money compare to buying 1 item at a time
3) Same as 2 but I pre-solder the 2560 for a contribution to my beer fund/cover the risk of <100% success rate J
4) 3 + I could solder the whole thing up for you if you just don’t enjoy that, for hobby fund level compensation ;)
This is PROBABLY the ultimate upgrade for the Thames Valley RepRap – we’ve got a batch of 10 PCBs and enough takers for all of those but this includes some duplicates and it’s not hard to order more PCBs and I keep many of the bits in stock for my business, so if you’re not one of the ones who already expressed solid interest, but you’re using your machine and might want to do this if it goes well, do get in touch. I’ll update here with progress, which I expect to happen in frequent little fits over the next few weeks!
Cheers,
Alex Gibson
+44 7813 810 765 @alexgibson3d 37 Royal Avenue, Reading RG31 4UR
admg consulting
edumaker limited
• Project management
• Operations & Process improvement
• 3D Printing
-----Original Message-----
From: tvrep...@googlegroups.com [mailto:tvrep...@googlegroups.com] On Behalf Of Alex Gibson
Sent: 30 September 2020 20:56
To: tvrep...@googlegroups.com
Cc: malcol...@gmail.com
Subject: RE: [TVRepRapUG] OMC-to-2560-Adapter
Hi John and Malcolm
Sorry, I've replied to both of you separately about this - my attempts to attach a photo seem not to please the Gmail overlords.
Unfortunately the boards, when they eventually arrived and I got round to opening them, were nothing like correct. In fact I think they were another person's boards, that happened to look quite similar!!!
I've re-ordered with another board house this evening... will let you know as soon as they get here!!!
Cheers,
Alex Gibson
+44 7813 810 765 @alexgibson3d 37 Royal Avenue, Reading RG31 4UR
admg consulting
edumaker limited
• Project management
• Operations & Process improvement
• 3D Printing
-----Original Message-----
From: 'John Brown' via TVRepRapUG [mailto:tvrep...@googlegroups.com]
Sent: 27 September 2020 15:25
Subject: [TVRepRapUG] OMC-to-2560-Adapter
Alex,
What is the state of the adapter? In Your June post you gave the
impression that things were imminent.
I would appreciate knowing if there is a problem and it is not going to
happen.
I understand if you have other priorities but it would be good settle
things and move forward and investigate other possibilities.
Maybe some assistance may help?
Regards
John Brown.
--
This email has been checked for viruses by AVG.
--
---
You received this message because you are subscribed to the Google Groups "TVRepRapUG" group.
To unsubscribe from this group and stop receiving emails from it, send an email to tvreprapug+...@googlegroups.com.
To view this discussion on the web, visit https://groups.google.com/d/msgid/tvreprapug/33bd6485-bb55-6a82-d06a-d0d514ab6015%40talktalk.net.
--
---
You received this message because you are subscribed to the Google Groups "TVRepRapUG" group.
To unsubscribe from this group and stop receiving emails from it, send an email to tvreprapug+...@googlegroups.com.
To view this discussion on the web, visit https://groups.google.com/d/msgid/tvreprapug/000501d69763%24c1707ee0%2444517ca0%24%40alexgibson.net.
