Search found 2835 matches

by roland
Sun May 06, 2018 8:07 am
Forum: acorn atom
Topic: New Atom owner - trying to determine mods
Replies: 10
Views: 424

Re: New Atom owner - trying to determine mods

The display looks great =D>
If you zoom into the picture it looks like the vga connector is plugged into the wall :lol:
by roland
Sun Apr 29, 2018 9:31 pm
Forum: upcoming and recent events & exhibitions
Topic: Dutch Atomic Techsat on Saturday June 2nd
Replies: 11
Views: 640

Re: Dutch Atomic Techsat on Saturday June 2nd

Looking forward to meet you Neil. Just bring something you're working on. Or just a good mood :lol:
by roland
Sun Apr 22, 2018 8:35 pm
Forum: general
Topic: Electron Forever E-Magazine Issue 1
Replies: 16
Views: 475

Re: Electron Forever E-Magazine Issue 1

That magazine looks very profesional. I hope that the Electron community provides a lot of input for it. Well done =D>
by roland
Wed Apr 18, 2018 9:17 pm
Forum: acorn atom
Topic: Atom 16 bit RISC
Replies: 6
Views: 351

Re: Atom 16 bit RISC

I didn't know you were working of this. Looking forward to see it on a techsat.

Btw, shouldn't it be COLOUR 3 :lol:
by roland
Thu Apr 12, 2018 10:49 am
Forum: acorn atom
Topic: Quantum Atom Challenge
Replies: 6
Views: 385

Re: Quantum Atom Challenge

Just a speculation, without any investigation of the datasheets: can it be caused by #B002 changing during the execution of the ADC #B002 instruction?
by roland
Wed Apr 11, 2018 9:00 pm
Forum: acorn atom
Topic: Quantum Atom Challenge
Replies: 6
Views: 385

Re: Quantum Atom Challenge

The first thing that pops into my mind is a glitch in the cpu or hardware. Perhaps a memory read error (bpl opcode 0x10 instead of bpl opcode 0x30 which has only one diiferent bit). I didn't run the routine yet, but is there any difference on what type of real Atom you run this? Original, Atom2k15, ...
by roland
Tue Apr 10, 2018 9:15 pm
Forum: introduce yourself
Topic: A new member
Replies: 17
Views: 551

Re: A new member

@oss003, @davidb, @Multiwizard, thanks! And nice to read that there are more dutch Acorn enthousiast here. :) Best regards, Erik Hi Erik, Welcome to this forum. I'd like to invite you for our annual techsat on the 2nd of June in Wijbosch. A famous village near Schijndel. It's very well known becaus...
by roland
Sun Apr 08, 2018 8:06 am
Forum: upcoming and recent events & exhibitions
Topic: Dutch Atomic Techsat on Saturday June 2nd
Replies: 11
Views: 640

Re: Dutch Atomic Techsat on Saterday June 2nd

Because 67% of the attendees wanted to start earlier, I changed the opening time to 10:00h ...... 8) Good job, as usual =D> Did you also contact the people that are not (very often) on StarDot but visit our meetings? Otherwise we seem to have only four attendees. The same weekend there is also an A...
by roland
Wed Apr 04, 2018 9:55 pm
Forum: acorn atom
Topic: Program Power Machine Code Monitor ROM
Replies: 8
Views: 527

Re: Program Power Machine Code Monitor ROM

I use the DISAS and STEP ( or TRACE ) statements regularly. They are in several expansion roms.
by roland
Mon Apr 02, 2018 9:13 pm
Forum: acorn atom
Topic: Micro Power Ltd Rom board
Replies: 24
Views: 638

Re: Micro Power Ltd Rom board

Hoglet wrote:(I have a local copy of all of these).


:shock: 8) :lol:
by roland
Mon Apr 02, 2018 7:49 am
Forum: off-topic
Topic: My Wife
Replies: 39
Views: 1466

Re: My Wife

Dear Ed,

Also my sincere condolences to you and your family. My thoughts are with you, your family and with Alison.

Roland
by roland
Sun Apr 01, 2018 10:21 pm
Forum: stardot.org.uk
Topic: Any home for the Acorn System?
Replies: 7
Views: 485

Re: Any home for the Acorn System?

I agree on renaming the forum. The computers have a lot in common and if there are too much posts for the System computers then we can always split the forum afterwards.
by roland
Sun Apr 01, 2018 10:15 pm
Forum: upcoming and recent events & exhibitions
Topic: Dutch Atomic Techsat on Saturday June 2nd
Replies: 11
Views: 640

Re: Dutch Atomic Techsat on Saterday June 2nd

oss003 wrote:
We start about 12:00 and the meeting ends about 17:00u.



That's only a half day :(

Nevertheless count me in. I will enjoy the lunch but unlike previous meetings I wont join the dinner after the meeting.
by roland
Sun Apr 01, 2018 10:42 am
Forum: emulators
Topic: MAME: Atom
Replies: 35
Views: 920

Re: MAME: Atom

I’ll have to switch on my Atom again as I’m losing my knowledge :?
by roland
Sun Apr 01, 2018 12:08 am
Forum: emulators
Topic: MAME: Atom
Replies: 35
Views: 920

Re: MAME: Atom

Pernod wrote:So what about these two sockets, make them switchable from #E000 to #1000? Are there any ROMs, except DOS, that are intended for these sockets?


IIRC the Econet rom was also at #Exxx.
by roland
Fri Mar 30, 2018 9:16 pm
Forum: acorn atom
Topic: Programmers toolbox rom
Replies: 8
Views: 296

Re: Programmers toolbox rom

Is it perhaps this one?

http://www.acornatom.nl/atom_handleidin ... olkit.html

Although the start address is different....
by roland
Sun Mar 25, 2018 7:50 pm
Forum: acorn atom
Topic: Acorn Atom newly acquired not resetting
Replies: 19
Views: 744

Re: Acorn Atom newly acquired not resetting

In a normal situation the CSS pin of the 6847 is connected to PC3 of the 8255 and it is used to select one of the colour sets of the 6847. You can check this by typing ?#B002=8 The colour of the text on the screen should change from green to orange (or something like that). If the colour does not ch...
by roland
Sun Mar 04, 2018 8:41 am
Forum: acorn atom
Topic: Crazy idea? Downgrade Electron to an Atom? Possible?
Replies: 19
Views: 828

Re: Crazy idea? Downgrade Electron to an Atom? Possible?

It is possible to upgrade an Electron to an Atom by either replacing the ula or the main board. Personally I would create a new main board and add the AtoMMC, more memory and a 6522. But the biggest problem is the keyboard. The Electron has four keys less than the Atom so it will never be 100% compa...
by roland
Sat Feb 17, 2018 11:33 pm
Forum: other vintage computer hardware, software and games
Topic: Finding a short circuit
Replies: 5
Views: 339

Re: Finding a short circuit

Well, the fitted eprom is a 27c256 and the original is a 27c128. So it's definitively the wrong eprom. Some unexperienced person might have thought to upgrade this computer by putting a 386 bios the wrong way on the motherboard and he probably hoped to run Windows for Workgroups 3.11 on it. :lol:
by roland
Sat Feb 17, 2018 8:19 pm
Forum: stardot.org.uk
Topic: Stardot logo fixed and now spud and banana free!
Replies: 57
Views: 1744

Re: Stardot logo infected with spuds!

I have just restored the original StarDot logo. So refresh your page or cache and see if it's back now....
by roland
Sat Feb 17, 2018 6:54 pm
Forum: other vintage computer hardware, software and games
Topic: Finding a short circuit
Replies: 5
Views: 339

Re: Finding a short circuit

Thanks for the hints, I'll try to remember them. But I have found the problem. There are two IC's in sockets. And guess what? Yes, both of them were inserted the wrong way. So they got there + and - swapped which caused the short circuit or high current. I hope they aren't damaged..... One of them i...
by roland
Sat Feb 17, 2018 5:19 pm
Forum: other vintage computer hardware, software and games
Topic: Finding a short circuit
Replies: 5
Views: 339

Finding a short circuit

The computer where I'm working on is a TRS80-M100 portable computer but the basic of the problem goes for many computers: how can I find the defect component that creates a short circuit? This computer had a failing power supply and I found out which transistor was defect. I replaced it and the powe...
by roland
Fri Feb 16, 2018 10:49 pm
Forum: stardot.org.uk
Topic: Stardot logo fixed and now spud and banana free!
Replies: 57
Views: 1744

Re: Stardot logo disappeared!

danielj wrote:I knew I shouldn't have tried to mess with it. I'll have another look tomorrow :(

d.


Daniel, I made a backup before upgrading so we should be able to restore it from there. I never noticed that the logo disappeared.
by roland
Tue Jan 30, 2018 9:53 pm
Forum: other vintage computer hardware, software and games
Topic: Variable phi2 frequency.
Replies: 2
Views: 266

Re: Variable phi2 frequency.

Prime wrote:
One potential pitfall is that IIRC timers in the VIA are based off the phi frequency are they not?




That is correct. Various timers, counters and the shift register use phi2 as the time base.
by roland
Mon Jan 29, 2018 7:41 pm
Forum: introduce yourself
Topic: Hello!
Replies: 11
Views: 561

Re: Hello!

Hi Telemedic,

Welcome to this forum, enjoy your visits here.

Does your Atom have any special hardware or software?

Greetings from the South of the Netherlands,
Roland
by roland
Mon Jan 29, 2018 7:39 pm
Forum: introduce yourself
Topic: Hello...
Replies: 11
Views: 493

Re: Hello...

Hello Ricardo, Welcome to this forum. Enjoy your visits here. I'm working on a similar project: using a Pi Zero as video adapter for my Atom. The Pi boots and waits for commands from the Atom. This is focussed on video output. More reading at stardot.org.uk/forums/viewtopic.php?f=44&t=11220 Gree...
by roland
Mon Jan 29, 2018 7:34 pm
Forum: introduce yourself
Topic: Hello from ZX Spectrum upgrade!
Replies: 10
Views: 554

Re: Hello from ZX Spectrum upgrade!

Hello Nick,

Welcome to this forum. Enjoy your visits here.

Greetings from the south of the Netherlands,
Roland
by roland
Fri Jan 26, 2018 7:35 pm
Forum: other vintage computer hardware, software and games
Topic: Received a belated Christmas present...
Replies: 15
Views: 1053

Re: Received a belated Christmas present...

Soon you'll not only need a bigger car but also a bigger attick 8) and what will be done with it? I will keep a few things, I will trade a few things, and I will give things away... I do not sell... If you trade each computer for a £10 banknote then you have enough banknotes to visit the next ABUG m...
by roland
Wed Jan 24, 2018 10:03 pm
Forum: off-topic
Topic: 40
Replies: 37
Views: 1857

Re: 40

The one fly in the ointment is that on a Raspberry pi when you switch it on you have to wait for Linux to load. The one thing I love about old computers is that you switch them on and the come on instantly! You can do bare metal programming on the Pi. Then it is instant on. You can use ARM assemble...
by roland
Wed Jan 24, 2018 2:35 pm
Forum: acorn atom
Topic: My New Acorn Atom :)
Replies: 63
Views: 2870

Re: My New Acorn Atom :)

I'm not going to remove my 32k daughter card and re-install the 7K of ram, You'd only have to remove the board and install IC's 51 and 52 (zero page) plus a 6502. The Atom detects if there's any ram at #2900 and if not it sets the program memory to #8200 (in video ram). Of course you cannot load an...