Search found 2817 matches

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: 175

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: 978

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: 175

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: 175

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: 978

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: 150

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: 269

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: 218

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: 286

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: 758

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: 27
Views: 918

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: 2073

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...
by roland
Mon Jan 22, 2018 1:46 pm
Forum: upcoming and recent events & exhibitions
Topic: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*
Replies: 143
Views: 6524

Re: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*

Just before we left I was looking for Arcadian to thank him personally for organising this meeting. Not only in the months/weeks/days before the meeting but also during the meeting. I noticed (especially on Saturday evening) that this is not always an easy job. But Dave, and all others who helped yo...
by roland
Sat Jan 20, 2018 7:20 pm
Forum: acorn atom
Topic: Daydreaming: a real VGA display card for the Atom
Replies: 73
Views: 5168

Re: Daydreaming: a real VGA display card for the Atom

Hi Dave, I'm still developing on my daydream. There is however a problem with the primitive that draws a triangle. I use this to draw rectangles by combining two triangles. You can see the error here (in the upper left corner, please click on the pictures for the correct view): IMG_2711.JPG IMG_2712...
by roland
Fri Jan 19, 2018 11:03 pm
Forum: upcoming and recent events & exhibitions
Topic: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*
Replies: 143
Views: 6524

Re: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*

danielj wrote:Do we have hot air in there? Do I need to bring the hot air?


There is plenty hot air in the sauna. So you just need to bring swim ware. If the room tomorrow is as cold as this evening I'll definitely visit the sauna a few times :mrgreen:
by roland
Thu Jan 18, 2018 8:37 am
Forum: acorn atom
Topic: My New Acorn Atom :)
Replies: 63
Views: 2073

Re: My New Acorn Atom :)

Is the power of the MMC2 board ok? Or is it increasing to appr. 5V after power on?
by roland
Wed Jan 17, 2018 9:11 am
Forum: acorn atom
Topic: My New Acorn Atom :)
Replies: 63
Views: 2073

Re: My New Acorn Atom :)

There's also a circuit with a TL7705 at http://www.acornatom.nl/atom_nieuws/198 ... 881075.htm
by roland
Sat Jan 13, 2018 5:24 pm
Forum: introduce yourself
Topic: Greetings and salutations
Replies: 9
Views: 311

Re: Greetings and salutations

Hello Jason, Welcome to this forum. Enjoy your visits here. If you want to read about a new beeb you can also read the Beeb FPGA topic at http://stardot.org.uk/forums/viewtopic.php?f=3&t=10295. Also my new Atom topic ( stardot.org.uk/forums/viewtopic.php?f=44&t=7858 ) is worth reading. Those...
by roland
Fri Jan 12, 2018 8:55 am
Forum: acorn atom
Topic: My New Acorn Atom :)
Replies: 63
Views: 2073

Re: My New Acorn Atom :)

Good work Walter =D> It looks great.
by roland
Wed Jan 10, 2018 9:06 pm
Forum: upcoming and recent events & exhibitions
Topic: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*
Replies: 143
Views: 6524

Re: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*

Perhaps if you place a few tiny drops of tin on each pad and then use the halogen light bulb (viewtopic.php?f=41&t=14296) you can repair the connector...
by roland
Wed Jan 10, 2018 5:05 pm
Forum: upcoming and recent events & exhibitions
Topic: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*
Replies: 143
Views: 6524

Re: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*

There are many people on the guest list that I don't know. Are there badges available or should every visitor create his (no women?) own badge so that I know who I'm talking too?
by roland
Tue Jan 09, 2018 8:54 am
Forum: upcoming and recent events & exhibitions
Topic: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*
Replies: 143
Views: 6524

Re: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*

Hello Dave,

I don't think that the model reallymatters, it is for an Atom so it's quite low resolution. It will also be connected to a Pi Zero, I'll bring the adapter from mini HDMI to VGA. Thanks in advance,

Roland
by roland
Mon Jan 08, 2018 8:41 pm
Forum: upcoming and recent events & exhibitions
Topic: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*
Replies: 143
Views: 6524

Re: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*

Now that we are back to the main topic I can ask for the last time .... "can anyone bring a VGA monitor for me?" I prefer to have two monitors but one will also do. If no one can bring me a VGA monitor then I'll have to leave my Atom at home and I can't show you some new (software) develop...
by roland
Mon Jan 08, 2018 8:31 pm
Forum: general
Topic: QIC tape and drive (from ABUG North booking info topic)
Replies: 17
Views: 336

Re: QIC tape and drive (from ABUG North booking info topic)

Moderator message: I have moved this topic because it was too off-topic for the original ABUG North booking thread.
by roland
Mon Jan 08, 2018 8:27 pm
Forum: upcoming and recent events & exhibitions
Topic: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*
Replies: 143
Views: 6524

Re: ABug NORTH User Group meeting | 19-21 JAN 2018 | MANCHESTER *BOOKING INFO*

The posts of the QIC tape and drives is very off topic, so I moved it to here.