Search found 45 matches

by atcurtis
Mon Jun 18, 2018 4:54 am
Forum: for sale / freebies
Topic: Worth Taking a Look At
Replies: 2653
Views: 218360

Re: Worth Taking a Look At

1024MAK wrote:
Sat Jun 16, 2018 1:39 pm
Elminster wrote:
Sat Jun 16, 2018 11:54 am
I guess one persons junk is another’s treasure, certain people in my household think any computer with less than 32 bits is junk. :)
Computers with less than 32 bits are a bit rare. A ZX80 has 1024 bits and that's just the RAM... :lol:

Mark
Don't you mean 8192 bits of RAM?
by atcurtis
Sun May 06, 2018 6:51 am
Forum: hardware
Topic: Mouse X Y doesn't work
Replies: 5
Views: 456

Re: Mouse X Y doesn't work

Going from memory but...
IIRC, there are an odd number of slots in the wheel.
If someone replaced the photodiodes but got the height not even, you don't get the proper quadrature output.
by atcurtis
Fri May 04, 2018 11:33 am
Forum: hardware
Topic: RiscPC Second CPU slot ARM possible?
Replies: 8
Views: 690

Re: RiscPC Second CPU slot ARM possible?

The 'first ever' risc pc second processor was an ARM. Used internally inside Acorn to test the bus mastering, one of them is now at the CCH in Cambridge, via the Chris's Acorns collection. http://chrisacorns.computinghistory.org.uk/32bit_UpgradesA2G/Acorn_ARM6102ndProc.html This of course was not a...
by atcurtis
Fri May 04, 2018 11:26 am
Forum: for sale / freebies
Topic: Worth Taking a Look At
Replies: 2653
Views: 218360

Re: Worth Taking a Look At

This should be in the LOL price section! :shock: Tynemouth Software can do this sort of thing as shown here:- http://blog.tynemouthsoftware.co.uk/2015/12/day-19-bbc-micro-usb-keyboard-kit.html Still there might be a muffin out there with more money than sense. :roll: :lol: To achieve the proper ret...
by atcurtis
Sat Apr 07, 2018 8:56 pm
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 575
Views: 47152

Re: Palettemate / enhanced video ULA with 4096 colours

Random thought:
If one ties the LPSTB line to the HSYNC, would that give one the ability to enable an IRQ per HSYNC using the system VIA?
(since light pens are essentially useless with modern LCD panels)
by atcurtis
Fri Feb 16, 2018 10:41 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 7355

Re: SpectROM - Speccy emulator for the Pi co-pro

I've heard of someone using the BBC Master shadow memory in order to double the vertical resolution with interlacing. Yes - I remember typing in a program that did this from Acorn User. Unfortunately, my monitor wasn't happy with it (or maybe I made a typo!) I remember that one, my eyes weren't ver...
by atcurtis
Thu Feb 15, 2018 10:01 am
Forum: hardware
Topic: Myelin's in-system updateable MegaROM for the BBC Master 128
Replies: 31
Views: 1679

Re: Myelin's in-system updateable MegaROM for the BBC Master 128

jgharston wrote:Hmmm.... there's a thought. Where's the video ULA in a Master? Will the nULA fit in without fouling anything?
The Video ULA is kinda under where the internal TUBE board is positioned.
by atcurtis
Thu Feb 15, 2018 9:54 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 7355

Re: SpectROM - Speccy emulator for the Pi co-pro

I've heard of someone using the BBC Master shadow memory in order to double the vertical resolution with interlacing.
by atcurtis
Tue Feb 06, 2018 9:40 am
Forum: hardware
Topic: Thought experiment: Iomega zip drive for the BBC
Replies: 10
Views: 568

Re: Thought experiment: Iomega zip drive for the BBC

Surely, removing the buffer/driver chip on the printer port would yield a second bidirectional port :wink:
by atcurtis
Mon Jan 29, 2018 6:20 am
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 203
Views: 7353

Re: RGB to HDMI using a Pi Zero and a small CPLD

Just noticed this one - it looks awesome! There is something similar for the speccy:- https://www.sellmyretro.com/offer/details/brand-new-zx-_hd-hdmi-interface-for-the-zx-spectrum-27558 I have a SpectraScart so don’t have one of these to know how well it works but there are some review links on the...
by atcurtis
Wed Dec 27, 2017 10:49 pm
Forum: hardware
Topic: A blitter for the beeb?
Replies: 59
Views: 4586

Re: A blitter for the beeb?

I've spent some time making an assembler protracker player. It does more effects but is by no means complete. It looks to me like it would be possible to have something like this running off interrupts during a game without eating too many cycles.... Anyway, I'll get back to hardware designing now,...
by atcurtis
Mon Oct 02, 2017 4:41 am
Forum: upcoming and recent events & exhibitions
Topic: Proposal: San Francisco Bay Area user group
Replies: 25
Views: 2546

Re: Proposal: San Francisco Bay Area user group

I think exhibiting Acorn computers would be a great idea since so few Americans even know of their existence.

Would be cool if someone had an early A310 machine to show off an example of 1987 technology. I tried to snag a A3000 from ebay but it moved out of my price range.
by atcurtis
Sat Sep 16, 2017 6:47 pm
Forum: for sale / freebies
Topic: VideoNuLA boards
Replies: 45
Views: 8017

Re: VideoNuLA boards

I'm definitely interested in a board for my BBC Master. It'll need intl shipping to the USA.
by atcurtis
Thu Sep 07, 2017 8:56 am
Forum: hardware
Topic: NuLA demos
Replies: 130
Views: 9648

Re: NuLA demos

What would be fun would be a combination of the NuLA + ARM Copro (Pi) with BasicV and extra stuff so that one can use simple programming in Basic and the graphics output drive the NuLA to get the rich colour mode.
by atcurtis
Mon Jul 17, 2017 10:15 am
Forum: for sale / freebies
Topic: Worth Taking a Look At
Replies: 2653
Views: 218360

Re: Worth Taking a Look At

vanpeebles wrote:I bet there is an old cupboard in a college or school somewhere full of those old servers.
Probably sealed behind drywall and everyone had forgotten that there was ever a cupboard there.
by atcurtis
Fri Jul 07, 2017 8:27 am
Forum: software: other
Topic: Anyone got Communicator system software? (Basic has 65816 assembler)
Replies: 70
Views: 5643

Re: Anyone got Communicator system software? (Basic has 65816 assembler)

I think it would be cool to clone since it's kinda a stepping stone between the classic Beeb and the Archimedes.

I wish I had the time ... but I'm just toying around with the idea to couple a 65816 + a few cplds + dram etc and put it in a BBC Master or Compact case...
by atcurtis
Sun Jul 02, 2017 11:16 pm
Forum: hardware
Topic: Vectorlight's A3010 IDE mod : step by step guide
Replies: 71
Views: 6223

Re: Vectorlight's A3010 IDE mod : step by step guide

I'd like to order a board if possible... I live in the USA.
by atcurtis
Mon Jun 26, 2017 1:16 am
Forum: software: other
Topic: Anyone got Communicator system software? (Basic has 65816 assembler)
Replies: 70
Views: 5643

Re: Anyone got Communicator system software? (Basic has 65816 assembler)

Here's my original 5184x3456 camera image of the "Communicator15" picture in case there's any more useful detail before it was cropped, resized and compressed: IMG_1516.JPG The era when BT approved devices used huge inductors to hold the telephone line off-hook instead of gyrator circuits. I guess ...
by atcurtis
Sat Jun 03, 2017 10:38 am
Forum: hardware
Topic: Today I overclocked my A3010
Replies: 291
Views: 19320

Re: Today I overclocked my A3010

AndyMc1280 wrote:Ooo very nice :D :D

What speed does that work at ? :wink:
Those parts are 50 ns so... 20MHz?
by atcurtis
Wed May 17, 2017 11:14 am
Forum: software: other
Topic: Anyone got Communicator system software? (Basic has 65816 assembler)
Replies: 70
Views: 5643

Re: Anyone got Communicator system software? (Basic has 65816 assembler)

Hmm... The fun thing will be how to work out the memory map since the whole of the first ROM can't be the whole of the first 64K because the stack has to live somewhere there. It looks like it uses the lots-of-modules approach like RiscOS and the COP entry looks like the inspiration for ARM's SWIs s...
by atcurtis
Tue May 16, 2017 6:37 am
Forum: software: other
Topic: Anyone got Communicator system software? (Basic has 65816 assembler)
Replies: 70
Views: 5643

Re: Anyone got Communicator system software? (Basic has 65816 assembler)

Were the ROMs ever dumped? I'm curious if BASIC on it supported the paging/large memory space or was it just running in 6502 mode.
by atcurtis
Fri May 05, 2017 2:49 pm
Forum: for sale / freebies
Topic: Worth Taking a Look At
Replies: 2653
Views: 218360

Re: Worth Taking a Look At

At today's crazy prices I think that's quite a good deal! Yes ! I rushed buying it NOW ... if it could be one with an Adelaide board, it would make my day / week / month :wink: For sure these days battery leak is a common 'gift' with these machines ... and it's even more atrocious when it's a mezza...
by atcurtis
Wed May 03, 2017 7:43 am
Forum: hardware
Topic: Myelin's USB Electron Cartridge Interface
Replies: 28
Views: 3127

Re: USB Electron Cartridge Interface

Interesting... Although I have a BBC Master. btw, is there an Acorn fan/user group in the San Francisco bay area? I'm in the south bay area. Oh good, someone else in this part of the world! I grew up in New Zealand, where Acorn machines were pretty dominant for a while, and wasn't sure if anyone el...
by atcurtis
Wed May 03, 2017 7:41 am
Forum: hardware
Topic: Myelin's USB Electron Cartridge Interface
Replies: 28
Views: 3127

Re: USB Electron Cartridge Interface

sydney wrote:myelin, atcurtis - you guys have seen the google maps thread, haven't you?

http://www.stardot.org.uk/forums/viewto ... =41&t=8933
Now I have.
by atcurtis
Tue May 02, 2017 8:31 am
Forum: hardware
Topic: Myelin's USB Electron Cartridge Interface
Replies: 28
Views: 3127

Re: USB Electron Cartridge Interface

Interesting... Although I have a BBC Master.

btw, is there an Acorn fan/user group in the San Francisco bay area? I'm in the south bay area.
by atcurtis
Tue May 02, 2017 8:17 am
Forum: hardware
Topic: My new project (don't tell Arcardian)
Replies: 35
Views: 2148

Re: My new project (don't tell Arcardian)

Looking at the datasheet... it may be possible to make it a board which replaces the ADC... with seperate audio output, of course.
by atcurtis
Mon Jan 30, 2017 2:02 am
Forum: hardware
Topic: A3010 hard disc interface
Replies: 159
Views: 20025

Re: A3010 hard disc interface

I don't have any other acorn machines, so it's impossible for me to know if any of my cards will work or not in advance of trying them. Have you tried formatting/partitioning on the machine directly with hform (which is where I get stuck)? I've thought for a while I should probably invert the signa...
by atcurtis
Mon Jan 30, 2017 1:58 am
Forum: hardware
Topic: A3010 hard disc interface
Replies: 159
Views: 20025

Re: A3010 hard disc interface

vectorlight wrote:
atcurtis wrote:Cool! Any spare bare PCBs for sale?
If you cover the postage you can have one for free. Just the bare PCB, no components. I'll make a list of all the components soon. :D
Sure... Tell me how much to pay via paypal to post it to the USA (where I live these days).
by atcurtis
Sun Jan 29, 2017 1:17 am
Forum: hardware
Topic: A3010 hard disc interface
Replies: 159
Views: 20025

Re: A3010 hard disc interface

I've built a version of this myself and have had some success with it. I've used a slightly different approach to munchausen and have built a board that plugs into the ROM sockets which saves soldering a about 19 connections :D Have booted it up today with a pair of known working CF cards and hey p...
by atcurtis
Tue Jan 10, 2017 9:25 am
Forum: hardware
Topic: Star LC-10 dot matrix printer
Replies: 15
Views: 2020

Re: Star LC-10 dot matrix printer

Actually most dot-matrix printers use/used the ribbon to lubricate the print head needles - at least with the genuine ribbons where the head lubricant is part of the ink formulation. Of course on a printer which has been dormant for a considerable period of time a little WD40 will help. Once given ...