Simply_Graham

Would one of those DC to DC converts offer a way to try this, there ment for isolation but I believe internally there both a both a Buck / Boost convertor 5V to 5V Just a thought as pretty small if it did solve the issue. https://www.digikey.co.uk/en/products/detail/mornsun-america-llc/B0505S-1WR3/13168098?s=N4IgTCBcDaIEIAYCsyDKBaAjAdRAXQF8g

I wonder if this would work on the XEGS that the NUC is based on or would this have the same issues as when you tried with the 130XE. Not many differences but perhaps enough, Wish you luck in getting this working.

Wow a lot of work there. I think the white looks great, wondering how you did the keys, are they adapted from the XE or maybe the ST line, or just painted with transfers, be nice to see in a future Blog update. ??

@Marek I'd be interested in a full set of boards to be shipped to GB. I do have the components you require perhaps we can come to some arrangement

@wildstar87 With a VGA to BNC cable all of the Signals are going in one direction, from the Computers VGA towards the monitor or BNC end (in this case) You are correct that to stop ground loops the typical arrangement is to have only one end grounded which should be the 'Transmission' end, the receiving end would usually terminate the ground or shell connection to ground via a capacitor. This stops any Ground loops occurring between the two items. Just as a side note if the transmission was in both directions the receive shield on each line would be capacitivly coupled to ground at each end the Transmit line being grounded. At the Din End Connect both Shield's to Ground and would be best to terminate the shield's within a bit of heat shrink and just connect the Chroma & Luma, hopefully using a shielded Plug that is grounded at the point it plugged into, so that the two shield's on Luma & Chroma remain separate and disconnected from each other and disconnected from the ground on the plug but going within the metal shell of the SVHS plug.

@Tickled_Pink Thank you for checking, that would put thge 2nd PIA chip as D100 to D103 then it would repeat over multiple times. D1xx is used by most perhaps all PBI Disk interfaces, i.e. Incognitio as one definate example . Would you mind checking the wires from the 2nd PIA to the 25 Way D socket ? pin 1 is GRD Pin 2 PA0 (PortA bit 0) PA0 to PA7 the 8 date bits Pin 3 PA1 -- The same down form to pin 9 -- Pin 9 PA7 Pin 10 PB0 These are likely control lines of some sort connected to PortB bits 0 & 1 Pin 11 PB1 and the 25 Way pinout should be this ... Pin 1 Ground should go to 18-25 Hence I'd expect pin 2 on the 25 way to go to pin 2 on the PIA It follows the 3-3,4-4,5-5,6-6,7-7,8-8,9-9. Pin 10 maybe pin 10 (ACK) and the same for pin 11 to 11 (/BUSY) although I think Strobe my need connecting but no 100% sure . I'll dig out my 1050 this evening, as I could use the ATR in Altirra to check port settings etc. All I need to do is convert a disc to an ATR, time to learn as not done one for ages.. Would you be able to take a picture of the dual O.S chip as well ? what kind of board is it in? is the switch on the back panel selecting one of the other.. Would be great if you have or Know someone that could dump the EPROM.

I've just found the original PIA from that 800XL , it looks a right mess, and clearly not my soldering on it .. Going by these pictures its Pin 23 thats wired off to someplace, I'd like to know where too.. Likely the 74LS138 chip, near the MMU (co60818) and of course the 11 pins on the side must go to the 25Way Once the ATR is uploaded would you have a printer on which to test it ? if so and it's working, if you can pass the wiring info back I'll make sure to draw up the circuit diagrams and release them as open hardware for anyone to use. BR

@_The Doctor__ Sorry no they didn't I'll dig them out over the next week or so, wont be able to do immediatly as my better half in in hospital. @Tickled_Pink It'd great that you have all the connections intact. I could really do with some nice pictures showing the pin connections between the PIA (either a 6520 or a 6821) on top of the original and the 25 Way socket. also would like to know the connection between pins 22, 23 & 24 almost certainly two of these are likely be tied to the original PIA it's sat on one however will go elsewhere... Wereabouts I'd really like to know, I already have an 800XL that originally had this fitted, I suspect it was a test machine that I ended up with when I was doing some development work for Computer House. The PIA was soldered on Top dead bug style any wires to the sockets were not present so I've no idea how it was wired, nor on what Address(s) the chip responds to, although I may be able to work this out using a de bugger. I'll sort out the ATR's as promissed above.

I´m still working on the SCCC V2. This one will come in two versions: Version A has Sophia-2 integrated, you need only ANTIC chips in PAL & NTSC to switch between TV norms. No soldering needed, no change of system crystal needed etc. (both versions). Version B will be like the current version, but requires also GTIA in PAL and NTSC - but no digital output or Sophia (any version) possible due to space restrictions. @tf_hh Wow I'm glad I've seen this post, I was going to contact you, and ask kindly if you would sell me a bare board, that way I could just add the components I wanted and a Sophia2. P.S whilst you are designing , any chance you could add a few additional jumpers so that the WDC65C02S can be used (Although this may need an additional buffer (or two) due to LS TTL levels.) P.P.S. And know idea why AA would not let me 'quote' you..

Wow @Mr Robotthat does look good... Thank you for the offer of re designing the back panel much appreciated.. I'll add that It'll take me some time as I like to build these projects myself from scratch, so until I have purchased some boards I wont know exactly where to place what for the best fit. @scorpio_ny Yep aware of the Digital Audio aspect of HDMI, there are units that will add standard Audio to HDMI but they are big and expensive. depending on space maybe able to add a BlueTooth Audio so at least a BT speaker can be used with your phone laptop or this, I'll have to see ?

@Mr Robot And thats the bit I have no experiance with what so ever ! I was thinking of an additional board much like the original DVI or the one by @hasanc but build escpecially for the NUC. PCB design I am o.k with I do understand @mytek when he used entirely Atari LSI, For me (maybe only me ) I'd like to have a small original based system that can output HDMI Video, just means when the world is to rights I'll be able to stay away and use my NUC and not an emulator or an FPGA design for the whole machine.

Hi @scorpio_ny Thanks for point me in to that post, and exactly what I'd though of doing but especially suited to fit in within the NUC, along with modded STL file's should Mt Robot be able to spare anytime on them. My thoughts were to have both a DVI version and an HDMI version especially designed to take the standard 16 oin Sophia2 cable with a mount for either HDMI or DVI. Modern hotel TV's don't seem to have a way of accepting composite video, so HDMI for those travelling seemed a good idea.

I'm wondering if a small board could be made that has an HDMI connector rather than DVI, I say this as I know the licencing issues regarding HDMI over DVI, however if we are talking about an alternative for use in this design, and the sophia is still supplied with the original DVI daughter card, would this be a way around it ? Showing Jan Beta with an Amiga fitted with a admitidly HDMI to HDMI extension cable Have a look around the 4 Min mark, shows an HDMI socket on a small PCB, with a different style of connector than Sophia uses, I'm sure a board could be designed for either connector that would fit an apropriately re designed case(s). If it help's, I'm happy to work with Mr Robot to make sure the PCB adapter design(s) are completed ?

@Mr Robot your most welcome, it's a shame that I live the wrong side of the pond, otherwise I'd love to be a little more involved, however my coding skills are not up to Jon's (FJC)as a for instance; however I do make my own additions to Atari's on the Hardware side. I've followed @mytek for some while and built both of his previous big projects the XEL & XLD. my preference is for a build from scratch bar the Mother board. I for some reason have always preferred Hardware, however I'm getting better at coding, as at some point I have to test the hardware I design although not items as complex as Simius or Candle have produced.

Oh dear looks like my head will be on the block ... especially using Metric .. Just remember the note about the plastic case at the edge connecter end having a different over hang from other cartridges. If it would help, I'm happy to send a cartridge over to you @Mr Robot @mytek & @Mr Robot Just like to congratulate you on turning out something so cute and 'nice' ??