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I agree with Dave. Just add the missing capacitor. I once broke L1 in an Atom and I just replaced it by a short piece of wire. I didn't notice the difference. On the other hands, I also once repaired an Atom with a lousy video signal and both C4 and L1 were bad.

Hoglet wrote some wise words about this back in 2013: https://stardot.org.uk/forums/viewtopic.php?f=8&t=2888&p=55936&hilit=AM26LS32#p55886 And maybe the attached diagram will help you. I have this still on my to-do list of projects with low priority. I already have the AM26LS32 somewhere in a bit bo...

I have received, build en tested the Yarrb Mini board. It does what it has to do and it works great in combination with an AtoMMC and it fits perfectly next to an Acorn colour board (pictures will follow later). yarrb-mini-comp-side.jpg yarrb-mini-solder-side.jpg I'll post the EPROM contents later t...

This is a very good start, looks great already

The TL866II Pro seems also to be able to program PIC 18F4525 which is used on the AtoMMC boards. Looks very interesting.....

I bought a Wellon VP598. It is a lot more money but programs PLDs no problem (except for some dodgy remarked Atmel chips the 866 will do!). What are your experiences with this programmer after two years of usage? I am considering buying this as well because my G540 learned to fly today. I really di...

I have received an EPROM with the label CP/M kaart on it, so this must be the BIOS for the Z80 board.

I also received a bunch of 3.5" discs with Atom CP/M software. They should be formatted in AtomDOS format. I have to work out a way to convert them to images.

Glad to hear that it is working now. Funny, you have a more recent version of the firmware than I have whilst I created the V4 board

Very cool. Can you also post a picture of the video adapter box? I want to include it on my (new) website

OK, You're on the list.

I contacted Theo, who has an Atom Z80 board with CP/M still up and running. He will send me an EPROM for the board and some discs with software.

I replaced the 47 ohm resistor again, and it has continued to work ok, running Asteroids 20 plus times. I will insert Rolands chips without the 47 ohm resistor, later tonite, to see what happens. O NO!!!! If it works ... don't touch it , leave it as is :lol: Roland, It may be a good idea for me to ...

Roland, can you check the photo here: https://stardot.org.uk/forums/download/file.php?id=63422&mode=view Is JP2 in the right position for a SY6502A? (For an NMOS 6502, don't you have to link pins 1 and 2, which I think are the left and centre pins?) JP2 is in the wrong position. Like Hoglet says, f...

Do you have enough 2114's to fill the complete video memory? If so, how does arcadians run with the 2114's?

I was also thinking about the noise killer board after seeing this screen corruption .... is it possible to remove the noise killer board and re-install two 2114's (just for the text mode) and how does the test program behave without noise killer?

If you send me your latest firmware I can also do some testing. Programming the PIC is no problem for me (probably not a big surprise ) .

I don't think that it matters that the IC's touch the solder contacts. The IC's are not conductive. The voltage is fine. Nice power supply btw. Does the Atom run stable with a simple program like this: 10 DO 20 PRINT "* " 30 UNTIL 0 Does it run for 10 minutes or so? And is there any difference with ...

Is the power supply stable? After a few minutes the Atom starts to behave faulty. This often indicates a temperature related problem. What is the voltage when the problems are starting?

I just got a message from Charlie: The V4 is based on a later board which has some re-arranged pins. Namely IRQ, which the PIC asserts at boot time. If you use the older V3 firmware this won't trigger. We need to change the following in atmmcio.h: #ifdef ATOMMC3PLUS // new board with IRQ pins moved ...

I don't know what firmware version I used :oops: I simply copied the firmware from the AtoMMC that I got earlier this year from Charlie. Maybe CommanderCoder can update the firmware with the latest version.IIRC that is possible with a special file on the MMC card, isn't it? I did check the value of ...

The pull-up resistor is 4.7kΩ so that is correct. I have never tested this setup with the new boards so I will have a look if my AtoMMC v4 generates an interrupt after a reset.

I just noticed this post now (almost one year and a week after the last post) and this must be enough to reconstruct the cable for the Electron and BBC. Since I have two of those MC Tape Systems I need two cables :lol: I'll report back when I have the wiring diagram .... I promise that it won't take...

The tapes are in nice shape! (well the boxes) I like the cassette player. never a box one like that. I have found the error in the cassette player. One IC has a very short circuit; it was easy to find. The power light was very weak and the voltage dropped from 10V to just below 3V. And within a min...

Keep hoping .... early December is sill a few weeks before Christmas. I don't mind if it will be delivered on the 24th of December
(I hinted my son for this as a present for me ... )

OK, thanks for the tip

I will try a 2 or 3 mm tip the next time. I have both available so that's no problem. And I must have some 0.8mm tin as well. But first I have to order new CPLD's and RAMs. I'll keep you informed, later.....

The solder iron tip is 1.2mm, tin is 60% tin and 40% lead.

I got a few extra ElkWiFi boards from PCBway (why???) and I decided to give it a new try to hand solder it. I still envy those people doing drag soldering .... I used lots of flux, a medium solder shaft and a drop of tin and in two seconds I had soldered nine CPLD pins together :mrgreen: I reused th...

And, although I definitely knew my onions, I now know how little I knew back in the day! :roll: BITD we didn't have the means to communicate like today. Some people might have access to a BBS system but AFAIK there was not so much exchange of knowledge like nowadays with the Internet, the social me...

I got two Electrons from Marktplaats. Considering the prices they go for lately, this was a bargain :lol: I haven’t tested them yet. The tape drive was sold as not working. 4B1781FB-452C-4BA5-89F2-3CA321AD9D58.jpeg 646335FD-B4F5-47D0-B00D-E4715F0D95D7.jpeg Edit: I just tested them. They work fine, n...

Somewhere in my archives there's a ROM image (and the sources of) GDOS. E.g. https://site.acornatom.nl/atomarch/Pc97-1/GDOS/Gdos15.src This file has a 16 byte header at the start. For the rest it's just an Atom assembler file. I don't have any ROMS or software for the Z80 board. I'll give it a try t...