Search found 797 matches

by paulb
Mon Feb 19, 2018 9:30 pm
Forum: general
Topic: little optimistic???
Replies: 25
Views: 800

Re: little optimistic???

With Acorn, we have the BBC B+ and Master 128 which don't have that much (games) software written to take advantage of the extra memory and hardware. I think that most people missed or ignored the BBC B+ - I don't think I was even really aware of it at the time - and the Master series was largely s...
by paulb
Mon Feb 19, 2018 4:19 pm
Forum: general
Topic: little optimistic???
Replies: 25
Views: 800

Re: little optimistic???

The 3000 had a 25mhz 68030; the top end 4000 had a 25mhz 68040 which managed about 18mips - not a slouch for the time but no better than the desktop Arcs or a 25mhz 486. Now that we have the benefit of hindsight, it is interesting to see how similar the fates of Acorn and Commodore were at the star...
by paulb
Mon Feb 19, 2018 3:54 pm
Forum: software: other
Topic: Hacking the school Econet
Replies: 15
Views: 436

Re: Hacking the school Econet

When we were at school my brother reckoned he knew someone at a neighbouring school who was so successful at hacking Econet that the teachers gave up and just let him have the system password. Looking back I'm not sure the story was true but it fascinated me at the time and I spent hours trying to ...
by paulb
Sat Feb 17, 2018 9:13 pm
Forum: general
Topic: little optimistic???
Replies: 25
Views: 800

Re: little optimistic???

Without industrial suppliers, is it actually possible to affordably fabricate each and every part of a BBC or Commodore 64 within a cottage industry? Given that there are custom ICs in these machines (the ULAs in the Beeb, Electron, and so on; the SID and VIC in the C64, I guess), people have alrea...
by paulb
Sat Feb 10, 2018 3:19 pm
Forum: hardware
Topic: Screen shadow memory
Replies: 18
Views: 540

Re: Screen shadow memory

So far as I'm aware, the Aries board was the original shadow RAM, as an expansion for the model B. It pre-dated the model B+. Indeed, I've often wondered whether they were in cahoots with Acorn from the outset, or whether Acorn then borrowed the idea. More information on this here , with Aries boar...
by paulb
Thu Feb 08, 2018 4:59 pm
Forum: hardware
Topic: P.R.E.S. AP3 and &E00
Replies: 24
Views: 471

Re: P.R.E.S. AP3 and &E00

I won an auction for a PRES AP3 + 3.5 inch drive off thatEbay yesterday and it should arrive in a few days. I know that the ADFS system used by the original Plus 3 and the AP3 both have a nasty habit of setting the memory to (IIRC) &1D00. I have a Master RAM Board and was wondering if that'll b...
by paulb
Mon Feb 05, 2018 3:42 pm
Forum: emulators
Topic: Elkulator compilation on Kubuntu 13.10
Replies: 11
Views: 1101

Re: Elkulator compilation on Kubuntu 13.10

ThomasHarte wrote:If you were willing to try an alternative, I'd be really grateful for feedback on the build process. I'm not generally fantastic at Linux-type tasks.


Reminds me of the wrappers I did for ElectrEm (Classic and Future!) a few years ago now.
by paulb
Mon Feb 05, 2018 3:39 pm
Forum: projects
Topic: Going great guns on a Prince of Persia port...
Replies: 197
Views: 13989

Re: Going great guns on a Prince of Persia port...

Depending on the amount of actual RAM needed, I wonder whether the Mega Games Cartridge could be used as a large data store with 16KBs of data paged in as required? Some kind of adjustable/scrolling window in the 16K sideways RAM/ROM region was done by various filing systems, and I did wonder wheth...
by paulb
Wed Jan 31, 2018 4:25 pm
Forum: software: classic games
Topic: Most disappointing conversions from other systems
Replies: 51
Views: 1908

Re: Most disappointing conversions from other systems

I don't think any of these were officially licensed releases. Maybe licensing was the kiss of death for the Beeb! Although not getting "licensed" ports possibly diminished the schoolyard credentials of the Beeb and Electron, both platforms were probably better off as a result. Most of the...
by paulb
Fri Jan 26, 2018 3:54 pm
Forum: software: classic games
Topic: Most disappointing conversions from other systems
Replies: 51
Views: 1908

Re: Most disappointing conversions from other systems

I would have to nominate Green Beret for being a terrible conversion, and just a terrible game in general. It's just too fast to be even slightly playable, and that scrolling is horrific. Green Beret was one of those games that seemed better than it actually was. But we should really be pairing up ...
by paulb
Fri Jan 26, 2018 3:50 pm
Forum: software: classic games
Topic: Most disappointing conversions from other systems
Replies: 51
Views: 1908

Re: Most disappointing conversions from other systems

SpyHunter. Loved playing the arcade version at the local sports center, then my mate got it on C64 and it looked (to my young eyes) as close to arcade perfect as was possible back then. I agree with the sentiment that you could probably do as well as that on the Beeb, too. Then I got it for my Beeb...
by paulb
Mon Jan 22, 2018 11:55 pm
Forum: hardware
Topic: Acorn's Second Processors and the Tube - what, and why
Replies: 21
Views: 1303

Re: Acorn's Second Processors and the Tube - what, and why

This (rumour) seems worth noting: The Tube was Acorn's way of resolving how a single machine could be all things to all people, as during the design phase one engineer wanted a dual-processor system, another reckoned one would do, chip designer Andy Hopper wanted it to be 16-bits and Chris Curry wa...
by paulb
Mon Jan 15, 2018 12:10 am
Forum: off-topic
Topic: How many people found computer self-assembly annoying?
Replies: 10
Views: 460

Re: How many people found computer self-assembly annoying?

Do you just sit around pondering topics that you think might get a rise out of people on here? I don't think that's very fair. I remember encountering microcomputers in the early 1980s, with books about them not yet featuring the BBC Micro, and the need to assemble a kit was a real consideration un...
by paulb
Sun Jan 14, 2018 9:08 pm
Forum: hardware
Topic: Which replacement parts are available new?
Replies: 5
Views: 333

Re: Which replacement parts are available new?

Maybe Unicorn Electronics' CRT/disk controller section can at least yield the 6845, if not the WD1770. Other established suppliers exist for older parts, too.

Edit: See also the 6500-series page for 6522 pricing on that site, for reference.
by paulb
Mon Dec 11, 2017 8:44 pm
Forum: software: classic games
Topic: Unused Citadel bits
Replies: 42
Views: 2194

Re: Unused Citadel bits

Arcadian -- I don't think a non-garbaged Electron version would be possible, unfortunately. The BBC version just reprograms the ... CRTC (??) ... to mask off those garbage areas. If the Electron doesn't have the hardware to do this, I don't think it's possible. You would need to save several kiloby...
by paulb
Sun Dec 03, 2017 7:37 pm
Forum: wanted
Topic: Would like to borrow: Hydra controller card
Replies: 15
Views: 863

Re: Would like to borrow: Hydra controller card

RISC OS was the operating system running on the Acorn computers ARM used to perform the demonstrations. This fact proves RISC OS was and is perfectly capable of multi-core operation. I'd be very surprised if that was ever the case. :roll: Maybe someone should tell ROOL, then, if it's that easy: Bou...
by paulb
Wed Nov 29, 2017 12:40 pm
Forum: hardware
Topic: A blitter for the beeb?
Replies: 49
Views: 2515

Re: A blitter for the beeb?

tricky wrote:I'm pretty sure that the NES 1983 had DMA and I seem to remember a thread around here about, I think DMA ideas for the elk.


DMA on the Electron
by paulb
Tue Nov 28, 2017 11:14 pm
Forum: hardware
Topic: A blitter for the beeb?
Replies: 49
Views: 2515

Re: A blitter for the beeb?

I remember the day we took delivery of our first Master 128 at school and being rather disappointed at the same 8 gaudy colours and lack of graphical improvements. Acorn's development focus was elsewhere, but at the time, the way the classic Beeb range was being stretched out was justifiably critic...
by paulb
Tue Nov 28, 2017 4:51 pm
Forum: hardware
Topic: A blitter for the beeb?
Replies: 49
Views: 2515

Re: A blitter for the beeb?

It seems clear to me that the address lines are _not_ released but _held_ (otherwise the slow ROM thing wouldn't work). Later processors in the series, I'm not sure when but certainly some WDC, have a BE input that when (de)asserted releases all the relevant lines. Whereas it is my understanding th...
by paulb
Tue Nov 28, 2017 3:40 pm
Forum: hardware
Topic: A blitter for the beeb?
Replies: 49
Views: 2515

Re: A blitter for the beeb?

I do use /RDY and /SYNC to hold the CPU. However, I also need to detach the CPU's address lines when blitting to/from system RAM as there is no way to tell an NMOS cpu to leave go the address and RnW lines. That's why at the moment it lives in the CPU socket. So unless there is some way of taking o...
by paulb
Tue Nov 28, 2017 1:53 pm
Forum: hardware
Topic: A blitter for the beeb?
Replies: 49
Views: 2515

Re: A blitter for the beeb?

On the Electron, you'd probably want to detect periods where the ULA isn't wanting to access RAM itself, and this might be easier in modes 0 to 3 because the CPU clock would actually be suspended and thus the test for ULA activity would be much easier. I just remembered that since the DMA controlle...
by paulb
Tue Nov 28, 2017 12:20 pm
Forum: hardware
Topic: A blitter for the beeb?
Replies: 49
Views: 2515

Re: A blitter for the beeb?

I started work a while back on a basic DMA controller and basic sound chip for my mk.2 6809 project which over the past month has morphed into a blitter chip for the BBC Micro. (For those who haven't heard of a blitter it is a chip that can copy memory from one place to another very quickly and opt...
by paulb
Mon Nov 27, 2017 10:15 pm
Forum: stardot.org.uk
Topic: https certificates?
Replies: 41
Views: 2140

Re: https certificates?

That's fundamentally missing the whole point of encryption - using Tor or a VPN you're just allowing people at the Tor/VPN end point to view the traffic. This really does need emphasising. Tor is largely intended to obscure the origin of traffic, not to protect that traffic from eavesdropping. And ...
by paulb
Mon Nov 27, 2017 8:59 pm
Forum: hardware
Topic: Acorn M4
Replies: 7
Views: 503

Re: Acorn M4

The chronology might be interesting here. Perhaps people were porting Unix to the ARM a lot earlier than we thought The first attempt was based around the Mach microkernel, and I just bet it happened around the same time as RISC OS Gold and the Victoria project - their moonshot was a rival for the ...
by paulb
Mon Nov 27, 2017 5:31 pm
Forum: hardware
Topic: Acorn M4
Replies: 7
Views: 503

Re: Acorn M4

Obligatory Chris's Acorns link which for once doesn't have much information. The chronology might be interesting here. Perhaps people were porting Unix to the ARM a lot earlier than we thought, in that it seemed from what people have said at various times and things like job adverts, Acorn seemed t...
by paulb
Thu Nov 23, 2017 12:01 pm
Forum: emulators
Topic: Clock Signal: now also for Linux and BSD
Replies: 13
Views: 611

Re: Clock Signal: now also for Linux and BSD

It similarly properly models the Electron output as interlaced, and obeys all of Paul Boddie's other observations as to behaviour . Nice to see you doing more emulator work, Thomas! I hope my observations are still valid given hoglet's heroic investigations with FPGA implementations, given that my ...
by paulb
Wed Nov 22, 2017 3:24 pm
Forum: hardware
Topic: Open Source Logic Analyzer Experiments
Replies: 134
Views: 6012

Re: Open Source Logic Analyzer Experiments

Maybe for a master machine version, it would be easier to create a bare cartridge with the required lines straight onto the board, or into sockets on the cartridge so the cypress board can be mated to the cartridge. Would probably have to be careful with the clearance for the board and the slot cov...
by paulb
Tue Nov 21, 2017 2:54 pm
Forum: projects
Topic: Going great guns on a Prince of Persia port...
Replies: 197
Views: 13989

Re: Starting a Prince of Persia port...

Separate the player sprites into 1bpp planes and only use 2 colours. A "large" one at the original sprite dimensions for the white pixels (~50% size give or take byte padding) and a second "small" one that is offset for the skin tone (currently magenta) pixels. This reminds me o...
by paulb
Mon Nov 20, 2017 3:22 pm
Forum: off-topic
Topic: Work experience BITD - claims to fame, and infamy
Replies: 15
Views: 783

Re: Work experience BITD - claims to fame, and infamy

In a commercial sense, that plainly worked for them, but it bears mentioning that until 1998 ARM hadn't succeeded in designing a CPU: StrongARM was designed by DEC, ARM6 and ARM7 were ARM2/3 in a fedora and dark glasses, ARM8 was a mess. In effect, they spent the first eight years of their existenc...
by paulb
Sun Nov 05, 2017 11:44 pm
Forum: software: classic games
Topic: "Unfixable bug" in BBC B Elite
Replies: 54
Views: 4494

Re: "Unfixable bug" in BBC B Elite

Well, I don't know as I never read any of that and how much they took or just used to build on, but there comes a point where it is normal to use what is there, in what should after many years be, the 'public domain'... Well, I'm sure things will get more interesting if Harry Potter ever shows up i...