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Old 14th Jan 2021, 11:11 pm   #101
SiriusHardware
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it may have failed due to age / helped by a bit of heat
I actually think it was killed by sheer bad luck, which is something which Buzby123 seems to specialise in. (All four of his original 2111 RAMs were dud as well, that was why his 'Slothie' issue VI originally couldn't be got working when his PROMs - he has / had two sets - were still all OK). He did mention he had a replacement DM74S571 (a blank specimen) on the way, but in the meantime he still has his 'Old OS' PROMs which are OK.

So what's the plan for the Softy now? Between yourselves and Tony you seem to have managed to make good progress, especially with verification of the EPROM contents. An extremely lucky break, for two such rare machines to have the same firmware. I assume there are plans to try to repair that one that Chris has access to - we don't seem to know yet whether Tony's has been powered up or whether he has plans to do that, perhaps not.

Are you thinking now to make a replica?
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Old 15th Jan 2021, 4:23 am   #102
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As regards the hex file of my Softy EPROM :

I read out the 2708 using something called a Ferret. This is a combined RS232 breakout box, interface converter (RS232, current loop, parallel), strip printer and EPROM programmer (!). It can handle the 3-rail EPROMs and claims to be able to output IntelHex and many other formats.

I had to read the EPROM on that, send the IntelHex file over the RS232 port to an HP 95LX, then kermit it onto this PC. At any point spaces could have been added, but I suspect the Ferret outputs them anyway. The original IntelHex format (which dates back to the early 1970s, my MCS8i can handle it for example) was used with paper tape and is specifically specified to skip over 'extra' characters. A hex converter program that doesn't skip until it finds a colon is broken!

But you now have the data and it agrees with one of the other Softies.

Incdentally, there is no serial number scratched on my Softy PCB.

Thanks for the info on what you did to read it - It sounds like it wasn't that easy a job, if you needed to use an HP95 in between (rather than direct to a PC Serial / USB-Serial convert port)!
I have recently seen some very early Data-I/O programmers that had a built-in paper-tape reader/writer in the top (and it wasn't too many years ago that a saw a PCB drilling / routing machine still in use in a PCB Manufacturing plant that had a paper-tape reader in it - although this part was not used for decades / if it was ever used at all).
I knew Intel-Hex and other Programming-File with Checksums etc. files were many decades old, but I hadn't realised until recently that they were ever used with paper tape as I would have thought magnetic media was becoming common at the same time as EPROM's and a bit surprisingly that paper-tape was still being used quite a few years after EPROM's had been invented.

It seems that most Hex-Editor programs are a bit 'broken'! - With only the Dataman-48 software reading an Intel Hex file with spaces at the start (I think 50 is a suspiciously round number, so was probably deliberately inserted somewhere, rather than occurring by accident). All the Hex-editors I've tried so far were not expecting any extra characters at the start. So need to do some manual editing etc. if you have a file with this

WinHex can't import .hex directly - you have to load it as a straight-binary, them convert its Intel-Hex format ASCII contents to True Binary - which fails with 'Conversion impossible. An invalid character was found at offset 0' (even on the latest version of the program).

ICY-Hexplorer (latest V2.6 2006) Imports 21 different formats, inc. Elektor & Tektronix ones. But using Intel-Hex on this gives a 'warning: ignoring garbage lines' (as well as no start address record) and it completely ignores the first line, resulting in shorter contents with rest of data shifted-up into wrong address. And I have seen a few reviews that this program didn't display their data correctly. Plus I've found its decimal checksums display do not seem to correspond to any produced by other programs, even with the right raw-binary data loaded.

HxD seems to be quite popular with many (Chris O lists it under the tools he uses for his Acorn / MK14 / Softy etc. replica work). And I found my V1.7.7.0 2009 (the last one to work on pre-XP Windows) was quite old, (with Import of Intel Hex not added until next version). I've now updated this to latest V2.4.0, although it also doesn't like extras characters at the start, giving 'Parse error while importing in line 1, column 1 ":" expected, but found " ".

Last edited by ortek_service; 15th Jan 2021 at 4:38 am. Reason: Splitting contents into separate reply
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Old 15th Jan 2021, 4:38 am   #103
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Default Re: Softy 1

Back to the Softy, after a previous posting of a picture of one with version 381 firmware, I'm wondering what the differences were / how many other earlier / later / in-between versions there were. The only (Construction & user instructions etc) Manual that I've seen / seems to have been scanned on the 'net, doesn't mention any specific version.

However, there seems to be at least 2 other manuals - that look a bit more extensive / professionaly-produced, from the photo here:
https://davidfcox.typepad.com/blog/2...-computer.html
(Which also has the above one, on the right of these). I seem to recall someone was going to try to make contact with him - possibly over the Tolinka & its firmware - but contents of any if the manuals there would be interesting)

And it seems that some of these original-Softy manuals were even supplied with the Softy-2 (maybe they hadn't got round to updating the manual, if the S2 worked basically the same - with many similar parts from look of internal photos posted earlier): https://www.worthpoint.com/worthoped...mmer-307527523

TonyDuell: I don't suppose you have any of the other manuals for yours / know what different areas they cover http://www.bygonebytes.co.uk/Softy.html has only shown the brief 'construction & user instructions' manual - So it might be you only got that one with version 304 firmware. And when the later 381 etc. firmware was supplied, they may have provided some extra manuals.
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Old 15th Jan 2021, 8:30 am   #104
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I used the HP95LX becuase it's a lot easier to fit something that size on my workbench along with the programmer, etc than to fit a PC there. And the built-in terminal program handles plain ASCII, Xmodem and Kermit transfers.

If I can digress for a moment, the Intellec MCS8i is probably the first 8080 development system, and the only EPROMs it supports are 1702s (256 byte, PMOS, odd power rails). So not surprisingly it supports paper tape, that was the way to get data from larger machines back then (FWIW the Cambridge University mainframe system had paper tape punches and readers in the late 1980s, I suspect I was the last person to use them...) But also remember that CP/M has the PUN: and RDR: devices even if they were rarely associated with that particular hardware. Mind you, the CP/M IOBYTE variable comes straight from the monitor program on that MCS8i which has an identical way of selecting devices and stores the setting as a byte at location 0003.
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Old 15th Jan 2021, 10:28 am   #105
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Default Re: Softy 1

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HxD seems to be quite popular..it also doesn't like extras characters at the start...
Briefly aside, I was in touch with the author of HxD about this very problem recently and he made me a patched (German) version to try, which was able to load Intel Hex with extraneous characters ahead of the line start ':' character or after the checksum byte. It worked OK, so hopefully that change will be included in the next 'mainstream' English language release of HxD.
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Old 16th Jan 2021, 5:31 pm   #106
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HxD seems to be quite popular..it also doesn't like extras characters at the start...
Briefly aside, I was in touch with the author of HxD about this very problem recently and he made me a patched (German) version to try, which was able to load Intel Hex with extraneous characters ahead of the line start ':' character or after the checksum byte. It worked OK, so hopefully that change will be included in the next 'mainstream' English language release of HxD.
Yes, When I recently download 2.4.0, I noticed that 2.5 was imminent / beta available - but maybe a bit too late to make it into that.

I was just looking through the manual for the interesting 'ME2700 Orphan EPROM Programmer' for data on the devices it supports - It does do most common 24pins inc. 2708 and option for IM6654 etc. -ve Vpp ones, (but only copes with later JEDEC std. pinout ones, so not the 1702 or MM5204 etc) - Info here, inc. manual and mention of other retro-EPROM programmers: https://forums.qrz.com/index.php?thr...rammer.536154/
And it appears to be open-source, as schematic / (Digi-key etc) parts-list is in manual (which also details you adding your own custom extra support for extra devices), and firmware source here: (So maybe only the PCB that you have to buy) https://drive.google.com/drive/folde...nB2cXpQM1RBMWs

And this ME2700 manual mentions it does support preceding characters in front of the records (to allow comments etc.) - but there is a disadvantage in doing this as it means a corrupted-start file isn't detected.

Maybe it / PC Hex-editors could just give a warning and allow the user the choice of whether to accept skip this until start of record character found.
(Although the Dataman-48 software doesn't let you know, and does default to auto-detection of Binary, even after selecting to open 'Hex files only, so you have to ensure you override the auto-detection to Intel-Hex for the correct data).
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Old 16th Jan 2021, 6:46 pm   #107
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Quote:
it may have failed due to age / helped by a bit of heat
I actually think it was killed by sheer bad luck, which is something which Buzby123 seems to specialise in. (All four of his original 2111 RAMs were dud as well, that was why his 'Slothie' issue VI originally couldn't be got working when his PROMs - he has / had two sets - were still all OK). He did mention he had a replacement DM74S571 (a blank specimen) on the way, but in the meantime he still has his 'Old OS' PROMs which are OK.

So what's the plan for the Softy now? Between yourselves and Tony you seem to have managed to make good progress, especially with verification of the EPROM contents. An extremely lucky break, for two such rare machines to have the same firmware. I assume there are plans to try to repair that one that Chris has access to - we don't seem to know yet whether Tony's has been powered up or whether he has plans to do that, perhaps not.

Are you thinking now to make a replica?
Regarding the Softy, Chris has now had a replica PCB made, he designed. And is just waiting for these to arrive from China, before he can build one up and test it (Probably with a 2716 adaptor, as neither of us can program 2708's yet - Although I do have a few around, once I can programme these)
So he will probably put a link to his replica page on it, once he's got that assembled and working, and will probably make surplus blank PCBs / ready-programmed IC's etc. available from him, like with the others he's done .

And I may build one up myself at some point (I still need to finish my MK14 - on one of his PCB's - Mainly needing to order some 2111's myself, once I've decided upon the best source for these. But was thinking of doing some adaptors to 2114's for now, as have loads of those and can also add more RAM with a bit of extra-decoding)

Chris was only sent the EPROM and PROM from the Bygonebytes Softy, for reading-out, which he's now posted back. But on a email Chris sent to me he said: Derek has powered up his SOFTY but its not fully working, he has video but garbage on the display, sounds like the CPU clock is running as the video needs that but its not executing anything ?

So it looks like that one needs some fault-finding, but from his website it seems he designs and builds quite a bit of hardware so should be able to do that - Although Chris might be able to assist him if required, to get it going again (especially once Chris has a working-replica himself, to compare with), as he's been doing for other Acorn System replica boards re-builders.

I presume Tony need a bit of space / time (and maybe find a suitable multi-rail PSU, if he hasn't got the original for it), to be able to power his up sometime, to see if it still works - Which it may well do so, if it seems EPROM and PROM do usually still work and can swap the CPU / PIA with an MK14 to test + spare RAM ICs aren't too hard to find.
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Old 17th Jan 2021, 10:50 am   #108
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Mainly needing to order some 2111's myself, once I've decided upon the best source for these. But was thinking of doing some adaptors to 2114's for now, as have loads of those and can also add more RAM with a bit of extra-decoding)
As you may know, the AMD AM9111 is a drop-in substitute for these and seems slightly easier to find than original 2111s. I'm running 9111s in my 'Issue VI'. It's also possibly worth looking for SAB2111, the Siemens version, which is not as well known as MM2111, upD2111, etc.

One of my suggestions for Slothie for his next revision of his 'issue VI' was that it should use 2114s -instead- of 2111s even if it just wastes the extra capacity available in those devices - they look superficially similar so they would preserve the general appearance of the machine, but they are not as expensive or as difficult to obtain as the 256 * 4 types.
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Old 17th Jan 2021, 11:27 am   #109
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Mainly needing to order some 2111's myself, once I've decided upon the best source for these. But was thinking of doing some adaptors to 2114's for now, as have loads of those and can also add more RAM with a bit of extra-decoding)
As you may know, the AMD AM9111 is a drop-in substitute for these and seems slightly easier to find than original 2111s. I'm running 9111s in my 'Issue VI'. It's also possibly worth looking for SAB2111, the Siemens version, which is not as well known as MM2111, upD2111, etc.

One of my suggestions for Slothie for his next revision of his 'issue VI' was that it should use 2114s -instead- of 2111s even if it just wastes the extra capacity available in those devices - they look superficially similar so they would preserve the general appearance of the machine, but they are not as expensive or as difficult to obtain as the 256 * 4 types.
It would be a 1 way trip to go tp 2114s since they aren't pin compatible despite the apparent similarity (i.e. making the board accept either type would hard). On the other hand, making that move and accepting the change to the basic design would mean you would have room on the board for 2k of ram, perhaps 1k in the 0x400-07FF range and the remaining 1k in the usual places the RAM and the RAM/IO shadows are. The decoder logic would be interesting....
I'm not sure how much further I want to go modifying the MK14 design, I'm already thinking in terms of just designing a SC/MP based machine from the ground up that supports the full 64k, NIBL and a decent (period) VDU/Keyboard a bit like one of Karen's creations. I'm also deriously considering building an Acorn System 1/2 replica which could have a SC/MP CPU and ROM card for experimenting with the SC/MP, whilst also providing a platform for other 8-bit CPU's I have in my "collection" (6809, 6309, 6800, 6502, z80, 8085....)
TBH for people with problems getting memory (and for the future?) I'd consider just making an external EPROM and RAM card with some kind of GAL or PROM address decoder to plug in the back and provide all the memory, and leave the onboard IC positions unpopulated.
Given that the Memory, CPU and I/O chip are all becoming rare, hardware replicas are probably going to have to embrace newer technology and I wonder if an amped up PIC14 wouldn't be a more fruitful avenue.
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Old 17th Jan 2021, 11:33 am   #110
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I presume Tony need a bit of space / time (and maybe find a suitable multi-rail PSU, if he hasn't got the original for it), to be able to power his up sometime, to see if it still works - Which it may well do so, if it seems EPROM and PROM do usually still work and can swap the CPU / PIA with an MK14 to test + spare RAM ICs aren't too hard to find.

Yes, I don't have the original PSU so I would have to kludge something up. I do hae things that can take the RF output though. Alas my MK14 is currently missing the SC/MP and it never had the 8154. I do have other things I can 'borrow' those from though. But given I could read out the 2708 in my Softy and the dump agrees with at least one other I suspect that part is good. If the character generator PROM has failled it will be fairly easy to detect. Getting the Softy working doesn't worry me, I've done a lot worse.

My bench is currently occupied by something even older but calculating-related. A Brunsviga wind-the-crank calculator that was gummed up with something like WD40. So far only one tiny part has gone into hyperspace...
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Old 17th Jan 2021, 1:14 pm   #111
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(Wince). A bit late to mention this now but when I'm working on something which I suspect might turn into an exploded diagram of itself I put the whole thing inside a large clear plastic bag and work with my arms inside, so that if something goes kachow it doesn't get very far.

Slothie, yes, I did mean replace 2111s with 2114s, and drop the 2111/9111/6561, but don't necessarily try to utilise the extra capacity. 2114s are still easy and cheap, and 2111s are not.
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Old 18th Jan 2021, 1:32 pm   #112
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Mainly needing to order some 2111's myself, once I've decided upon the best source for these. But was thinking of doing some adaptors to 2114's for now, as have loads of those and can also add more RAM with a bit of extra-decoding)
As you may know, the AMD AM9111 is a drop-in substitute for these and seems slightly easier to find than original 2111s. I'm running 9111s in my 'Issue VI'. It's also possibly worth looking for SAB2111, the Siemens version, which is not as well known as MM2111, upD2111, etc.

One of my suggestions for Slothie for his next revision of his 'issue VI' was that it should use 2114s -instead- of 2111s even if it just wastes the extra capacity available in those devices - they look superficially similar so they would preserve the general appearance of the machine, but they are not as expensive or as difficult to obtain as the 256 * 4 types.
It would be a 1 way trip to go tp 2114s since they aren't pin compatible despite the apparent similarity (i.e. making the board accept either type would hard). On the other hand, making that move and accepting the change to the basic design would mean you would have room on the board for 2k of ram, perhaps 1k in the 0x400-07FF range and the remaining 1k in the usual places the RAM and the RAM/IO shadows are. The decoder logic would be interesting....
>>
>>.
Yes, Chris used AM9111's on his, he managed to get for not too much. And I'd looked searched for these as well as any other prefix 2111's / some of the more obscure TMS4xxx etc. equivalents with different numbers.
But it was looking like 2111's / 9111's from Germany, via an online auction was currently the cheapest - but I had seen mention of receiving faulty ones, so was looking around at alternatives.

Yes, the 2111's do have the ground pin in a slight odd shifted-up by 1 position. But I seem to recall some of the pins lined-up, so it was possible to make a stack of IC-sockets adaptor. Plus one of the 2111 chip-select lines was connected to an address line / inverted version on the other socket. So coud just connect this to one of the unused addess lines on the 2114 (which didn't have as many chip selects, but I reckoned I might get away with a bit of diode logic to combine 2:1). Mapping a pair of 2114's remaining 512bytes into the free spaces for extra-RAM is a bit more tricky, but would be nice to not have to waste that.
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Old 18th Jan 2021, 1:53 pm   #113
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9111's from Germany, via an online auction was currently the cheapest - but I had seen mention of receiving faulty ones, so was looking around at alternatives.
That was me, and although it's true that one of four devices I bought was faulty the German supplier replaced it with a working one without any fuss whatsoever. I'd be happy to buy more from that source on the basis of my experience with them so far.
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Old 20th Jan 2021, 11:39 pm   #114
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9111's from Germany, via an online auction was currently the cheapest - but I had seen mention of receiving faulty ones, so was looking around at alternatives.
That was me, and although it's true that one of four devices I bought was faulty the German supplier replaced it with a working one without any fuss whatsoever. I'd be happy to buy more from that source on the basis of my experience with them so far.
Unfortunately it seems they may now have run out - if that was via an online auction site? (many sellers say last few, if they aren't using that to increase price) - as I do recall they were rather cheaper than current >£22 each + £14 delivery from cheapest seller on there in Germany - so > £100 for a set of 4 of AM9111's. Even a certain UK supplier, with notoriously high prices, are 'only' charging £17.50 inc. free delivery. And can get (more collectable?) 2111's cheaper on there.
The current cheapest AM9111's on there is from USA (£5.60 - 20% Ltd. time offer = £3.74 each) - which would be quite good if the £13 delivery didn't nearly double cost for 4!
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Old 21st Jan 2021, 12:40 am   #115
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The AM9111s I bought from Germany are my 'while I can still get them' spare set, the four fitted in my issue VI were about $6 each from the USA, very reasonable, but then postage on top of that, then duty, then being charged for being charged duty took the price up to around £45. By comparison the ones from Germany cost exactly what they were priced at and the service from the seller was exemplary.

By contrast, I had a run-in with that notoriously expensive UK seller recently when they supplied labelled, programmed (therefore useless) PROMs and then when they were complained to, sent out more useless programmed PROMs to replace them, but with the labels conspicuously removed. And then they fiercely resisted taking them back for a refund, although they eventually did. I won't ever deal with that outfit again.
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Old 21st Jan 2021, 1:08 am   #116
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The AM9111s I bought from Germany are my 'while I can still get them' spare set, the four fitted in my issue VI were about $6 each from the USA, very reasonable, but then postage on top of that, then duty, then being charged for being charged duty took the price up to around £45. By comparison the ones from Germany cost exactly what they were priced at and the service from the seller was exemplary.

By contrast, I had a run-in with that notoriously expensive UK seller recently when they supplied labelled, programmed (therefore useless) PROMs and then when they were complained to, sent out more useless programmed PROMs to replace them, but with the labels conspicuously removed. And then they fiercely resisted taking them back for a refund, although they eventually did. I won't ever deal with that outfit again.
Yes, the dreaded import duty, and worse still the admin fee plus tax on the whole cost inc. delivery.
I presume we're still exempt from charges for ones from the EU at least.

I think my friend Chris originally got his (DM)74S571 PROM's from that UK seller, when they weren't charging anywhere near so much, but they sent less than what was ordered. And it took him a while to keep chasing them to see about the missing one, as it seem their sources were running out. But in the end they ended-up sending him the whole amount ordered, so he got a free spare. They were blank, but they did take a lot of retries to program - often taking 10-20 attempts to program many locations, having to keep pressing repeat (where it went back to start, as it verified each location after programming). But finally managed to get them verifying all OK.
So not sure if these old-stock ones had now become a bit dodgy, or if the (Dataman rebadged-ELNEC) programmer's algorithm settings weren't too good - Although it worked first time on some Tesla MH74S287's.

I noticed the UK seller was now advertising 'Generic' 74S571's - Still at higher DM74S571 prices, but from pictures etc. looks like you'd most likely get MH74S571's and so not much good for many people, who don't have access to a programmer that does the Tesla ones.
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Old 21st Jan 2021, 1:49 am   #117
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As we all know there are no 'generic' 74S157s, there are only DM (Nat Semi, widely programmable) and MH (Tesla), programmable by only a handful of high end commercially made programmers. If sellers have DMs they will say so, but if they are being non specific / evasive they are 99% likely to be Tesla. Texas, another notable PROM maker, don't ever seem to have made an SN74S571 although they did do an SN74S287.

My Hi-Lo Systems All07A has never failed to program a DM device first time as long as they were blank in the first place, so Chris's experience with those devices sounds quite extreme. We have also recently tried a pair of Philips / Signetics N82S131N in an MK14 and they work fine.
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Old 21st Jan 2021, 10:49 am   #118
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Hi All

I've finally decided to register on the forum as the Softy thread continues.

I am still waiting for my Softy 1 Replica PCBs to arrive, they are probably on a plane somewhere between Hong Kong and here ! Everything is ready to load and test the board when it arrives, I'll keep you posted on progress (or watch out at http://www.theoddys.com/acorn/PROMs%...1/softy_1.html).

(Owens friend) Chris
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Old 21st Jan 2021, 1:50 pm   #119
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Welcome Chris, good to have you here. From what we've heard about you from Owen you obviously are a good fit for this forum, as is Owen.

This is probably a good moment to to steer this thread back onto the subject of the Softy itself - we look forward to seeing one of your replica units in action.
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Old 21st Jan 2021, 6:05 pm   #120
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Welcome Chris, good to have you here. From what we've heard about you from Owen you obviously are a good fit for this forum, as is Owen.

This is probably a good moment to to steer this thread back onto the subject of the Softy itself - we look forward to seeing one of your replica units in action.
Indeed welcome - I look forward to this as I really want to build one of these so any updates on the Replica will be welcome - it is so important to preserve these early systems and capture the detailed knowledge about their operation.
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