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Vintage Computers Any vintage computer systems, calculators, video games etc., but with an emphasis on 1980s and earlier equipment. |
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17th Jan 2023, 5:38 pm | #21 | |
Pentode
Join Date: Nov 2022
Location: Chesham, Buckinghamshire, UK.
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Re: SoC Mk14 Pico Uploader
Quote:
The main reason for using them was most efficient use of board real estate - without going down the surface mount route. |
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17th Jan 2023, 6:38 pm | #22 | |
Octode
Join Date: Mar 2020
Location: Kitchener, Ontario, Canada
Posts: 1,298
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Re: SoC Mk14 Pico Uploader
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17th Jan 2023, 6:58 pm | #23 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
Posts: 11,586
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Re: SoC Mk14 Pico Uploader
I think DavidMS did say earlier that he was placing contact fingers on both sides of the PCB edge.
I would agree that with the possibility of various types of 0.1" pitch connectors which may be pressed into service, those contact fingers should be as long as they reasonably can so each finger has a large area attached to the PCB. Of course we are probably saying this mere seconds after DavidMS pressed the 'order' button. |
18th Jan 2023, 12:53 am | #24 | |
Octode
Join Date: May 2018
Location: Northampton, Northamptonshire, UK.
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Re: SoC Mk14 Pico Uploader
Quote:
Thanks for info. So as there wasn't an official 40-key keyboard, was there any / several other 3rd party ones sold / designs published? Yes, one of the MK14 designers wanted to produce a more-advanced computer with a better-processor, but apparently Clive Sinclair wanted to stay with the SC/MP (before he must have eventually been persuaded to go with the Z80 and the Zx80). So they'd left to form Acorn, which did start-off using the 6502 on System-1 (Albeit also with basically the same Keypad & display), which could be expanded into System-2 etc with VDU and ASCII-Keyboard. But I wasn't sure if you could produce the full Alphabet on any VDU boards for the MK14 - Chris is looking to produce some (updated with some more-available period components) 'replica' VDU boards, to get experirence with that - As well as doing an enhanced MK14, with substitution of the expensive SRAM's, and PROM's, for cheaper & higher memory capacity SRAM's / EPROM, to support other SC /MP OS's like ELBUG. So was interested in also adding a full-keyboard (Especially if other SC/MP OS's of the time, supported one). |
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18th Jan 2023, 1:19 am | #25 |
Octode
Join Date: Mar 2011
Location: North Yorkshire, UK.
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Re: SoC Mk14 Pico Uploader
The next logical development of the MK14 would surely be a NIBL basic machine with maybe one 4k page of ram, very much like the PICL
or maybe Ronald Deckers SC/MP with NIBL and FP basic. NIBL is actually very capable and ideal for hobby & educational use, integrating well with SC/MP M/C. Tim found some evidence of a SCRUMPI 4 from Bywood which would certainly have been a serious contender but for JMK's unfortunate passing at a young age Last edited by Phil__G; 18th Jan 2023 at 1:26 am. |
18th Jan 2023, 9:26 am | #26 | |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
Posts: 11,586
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Re: SoC Mk14 Pico Uploader
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26th Jan 2023, 5:57 pm | #27 |
Pentode
Join Date: Nov 2022
Location: Chesham, Buckinghamshire, UK.
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Re: SoC Mk14 Pico Uploader
PICO uploader PCBs ordered
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26th Jan 2023, 10:31 pm | #28 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Re: SoC Mk14 Pico Uploader
I would certainly be interested in buying one of your surplus PCBs from you David - I can never have too many uploader options...
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6th Feb 2023, 12:36 pm | #29 |
Pentode
Join Date: Nov 2022
Location: Chesham, Buckinghamshire, UK.
Posts: 135
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Re: SoC Mk14 Pico Uploader
PCBs arrived this morning, all very exciting
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6th Feb 2023, 1:48 pm | #30 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Re: SoC Mk14 Pico Uploader
I assume you'll want to populate and test the first one yourself, but when you're happy with them please PM me with details of how I can order one of your spare PCBs.
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6th Feb 2023, 2:03 pm | #31 |
Pentode
Join Date: Nov 2022
Location: Chesham, Buckinghamshire, UK.
Posts: 135
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Re: SoC Mk14 Pico Uploader
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19th Feb 2023, 1:36 pm | #32 |
Pentode
Join Date: Nov 2022
Location: Chesham, Buckinghamshire, UK.
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Re: SoC Mk14 Pico Uploader
After a bit of work related delay I have managed to get the PICO uploader board built and working. There are a couple of minor errors on the PCB layout but I was able to fix all but one by adjusting the s/w. The remaining one being the reset connection which I reversed, which is an easy mod. More annoyingly I assigned the button and jumper function text to a layer ignored by the gerber generator - hence the labels. The s/w is functional but I need to do a bit more work on the setup function. I am away with the day job this week but should get some time in the evenings to do a bit of write up.
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19th Feb 2023, 8:07 pm | #33 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Re: SoC Mk14 Pico Uploader
Looks very promising, it could become a regular on the exhibition circuit as it looks so easy to use and self-contained in a similar way to Coolsnaz2's M5Stick setup.
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3rd Mar 2023, 2:36 pm | #34 |
Pentode
Join Date: Nov 2022
Location: Chesham, Buckinghamshire, UK.
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Re: SoC Mk14 Pico Uploader
I have finally managed to upload an initial set of documentation to github and copied here. The s/w is still somewhat raw around the edges but is functional - it's certainly not pretty. The hardest bit to get sorted had nothing to do with the core functionality, but was around updating menu settings - It is written in CircuitPython which while offering some advantages over micropython does not offer an elegant route to manage multiple sources wanting to write to the file system. Anyway here it is. I will try to do a bit of tidy up of the s/w over the next week. I have not posted Gerbers as this stage as there are some minor errors on the V4 PCB and want to avoid putting something out which I know is wrong.
https://github.com/DavidMS51/Pico-Uploader.git |
3rd Mar 2023, 3:36 pm | #35 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Re: SoC Mk14 Pico Uploader
Thanks for your continuing work on this - if you want to offload one of the not quite perfect PCBs I think I can cope with having to swap the reset-out connections.
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9th Mar 2023, 3:36 pm | #36 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Re: SoC Mk14 Pico Uploader
DavidMS was kind enough to send me one of his current-issue (V4) PCBs for this project (Thanks David) and I have it about 95% built as I write this. Just have to finish it off and try to find a time slot during which I can actually try it out at home. (At the moment, work is somewhere I come to for a bit of peace and quiet).
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10th Mar 2023, 4:55 pm | #37 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Re: SoC Mk14 Pico Uploader
I've just noticed a possible issue with the instructions for setting the links for the reset output. When SOC modified the circuit to remove the unwanted PROM images in issue V PCBs they had to 'borrow' one of the gates which had originally been used in the reset circuit input, and because of that the reset switch circuit was modified with the +V end of the reset capacitor hard connected to +5V and the resistor going from the capacitor -Ve down to 0V.
In the arrangement for original MK14s you have assumed that the +VE end of the capacitor is always connected to the input of the reset circuit, but on an issue V, tying the reset opto-output emitter to 0V and having the flying lead going to the capacitor +VE lead will attempt to short the +5V supply to 0V, although the limiting resistor R1 will ensure there is not an actual short. That is why, on the original Pi-uploader design, the reset-output opto-transistor's emitter is not taken to the 0V track which all MK14s have on the keypad edge connector - instead it is taken out on a second flying lead which is intended to be connected to the reset capacitor -Ve and not specifically to 0V. So for original MK14s (or specifically for the issue V, of which Martin L's Czech replica is an exact clone), the user will need two flying leads coming off the interface and going to the capacitor +Ve and capacitor -Ve. The reset-opto's emitter should not be tied to 0V. |
10th Mar 2023, 6:03 pm | #38 | |
Pentode
Join Date: Nov 2022
Location: Chesham, Buckinghamshire, UK.
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Re: SoC Mk14 Pico Uploader
Quote:
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10th Mar 2023, 6:19 pm | #39 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Re: SoC Mk14 Pico Uploader
This is how mine is getting on so far. I used individual surface-mount optos because we have a lot of them at work and I used the same type on the Pi-Uploader so I know they work OK for this purpose. The pins on the SM optos only just reached the pads intended for DIP parts but in a way that was a good thing because it forced me to position them very precisely and make a neater job than I might have otherwise.
I don't have a JMP replica so I've hard linked the jumpers for 'normal' MK14 keypad connection layout. I've gone with a right angled pin row connector for the output connections because my already existing Arduino version of the uploader has the same type of output connection and a ready made connection cable+ 16-way edge connector, so that will speed things up a bit. I haven't fitted the backlight resistor or links yet. Now I just have to find the time to load the PICO up, when I can get a bit of time to myself. |
10th Mar 2023, 7:04 pm | #40 |
Dekatron
Join Date: Aug 2011
Location: Newcastle, Tyne and Wear, UK.
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Re: SoC Mk14 Pico Uploader
I've just stolen a few moments to shovel the software onto the Pico - It's now come to life although unfortunately it turns out that the display I picked out of a pile of junk somewhere has some vertical Pixel lines missing.
I'll let you know when I've actually had a chance to try uploading with it. |