Search found 1939 matches

by RobC
Thu Feb 22, 2018 6:58 pm
Forum: hardware
Topic: A5000 Boot Error (Error Number &80000003)
Replies: 15
Views: 248

Re: A5000 Boot Error (Error Number &80000003)

Andrewcee wrote:no idea what to do about the Ram control line failure?

First thing to do is to check the memory size links just in case a memory upgrade has been removed.
by RobC
Thu Feb 22, 2018 11:09 am
Forum: hardware
Topic: A5000 Boot Error (Error Number &80000003)
Replies: 15
Views: 248

Re: A5000 Boot Error (Error Number &80000003)

I've definitely had an Arc that had bad ROMs but can't remember which model it was (possibly an A3020). However, it's worth reseating the ROMs and checking the sockets for corrosion or damage (unless you've got a spare set of ROMs lying around). Also, check that any ROM size links are set correctly.
by RobC
Tue Feb 20, 2018 5:53 pm
Forum: hardware
Topic: A310: could blown C37 cap break monitor sync and WIMP GUI?
Replies: 8
Views: 263

Re: A310: could blown C37 cap break monitor sync and WIMP GUI?

Welcome to the forum. The loss of sync/booting to BASIC would seem to indicate a CMOS RAM issue - have you tried resetting it? Try holding down the delete key as you power on the machine and see if that makes any difference. If you can tell us which sort of monitor you are using, we should be able t...
by RobC
Mon Feb 19, 2018 10:34 pm
Forum: hardware
Topic: B+64K - 12k sideways ram working
Replies: 15
Views: 489

Re: B+64K - 12k sideways ram working

I used to use my B+ as my main machine but the Master has been my machine of preference for a good number of years now. My two main issues with the Master are the lack of the speech interface and that there's only room inside for one 16KB ROM before you start to lose SWRAM. I know you can use cartri...
by RobC
Mon Feb 19, 2018 8:53 pm
Forum: hardware
Topic: Backup from old SCSI HDD
Replies: 8
Views: 256

Re: Backup from old SCSI HDD

According to its documentation, GoSDC can back up from a physical ADFS hard drive. The relevant command/tool is SDCADI AN: "'SDCADI AN' (Add Disc ADFS Non-interlaced) is used to add ADFS type floppy or hard discs, with either a disc image file or a physical floppy or hard disc as the source.&qu...
by RobC
Mon Feb 19, 2018 4:16 pm
Forum: archive submissions
Topic: DOS software
Replies: 30
Views: 1691

Re: DOS software

Wow. Thanks again Marcus for all your hard work =D> For anyone looking to transfer these .IMG files to an ADFS hard drive image for use with a DC, GoSDC, BeebSCSI etc., here's how I managed to do it using Windows 10: 1) Download a copy of ImDisk 2) Extract the DRIVE_C file from the DOS folder of you...
by RobC
Mon Feb 19, 2018 9:17 am
Forum: hardware
Topic: Can I use this to hook my Amiga to the CUB?
Replies: 8
Views: 216

Re: Can I use this to hook my Amiga to the CUB?

I know that the contrast knob doesn't work if you put the Cub in analogue mode.
by RobC
Mon Feb 19, 2018 8:49 am
Forum: hardware
Topic: Can I use this to hook my Amiga to the CUB?
Replies: 8
Views: 216

Re: Can I use this to hook my Amiga to the CUB?

Here's the Cub analogue links diagram from Mike Cook's Chameleon article - I dug it out a while back for people who wanted to use a Cub with VideoNuLA...

cub_analogue.png
Cub analogue RGB mod
by RobC
Sun Feb 18, 2018 12:49 pm
Forum: emulators
Topic: When should keyboard interrupts be enabled during startup?
Replies: 4
Views: 139

Re: When should keyboard interrupts be enabled during startup?

hoglet wrote:I have a suspicion the keyboard status is normally polled off the 100Hz timer interrupt.

Yes - the System VIA Timer 1 is set to go off every 10ms and this triggers the polling of the keyboard.
by RobC
Fri Feb 16, 2018 8:38 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

The Oric is another one I've emulated! Unfortunately it doesn't have 8x1 attributes, it has 6x1 Ah! I just saw that attributes could be changed per scanline and assumed they were 8x1. I did own an Atmos for a bit so should have paid more attention! (EDIT2: it's only 240 pixels across though, so if ...
by RobC
Fri Feb 16, 2018 5:43 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

The Camputers Lynx may be easier than the CPC, it also uses a 6845. Not so much software out there for it though. I have a Lynx and think it can do 8 colours at something like 256x256 with no attribute clash. Again, the 12MHz attribute mode might get close but it's not quite good enough. And as you...
by RobC
Fri Feb 16, 2018 5:01 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

Thanks Thomas - I'll take a look at those games. Also, the info on the CPC is very useful as I'm not very familiar with it apart from knowing that it uses a 6845! I'd thought about the MSX-type machines as I have an Einstein and know a little bit about it. The sprites are a problem as each can have ...
by RobC
Fri Feb 16, 2018 1:54 pm
Forum: hardware
Topic: Music 5000 - sound generation
Replies: 12
Views: 403

Re: Music 5000 - sound generation

On a semi-related note, would it have been possible to intercept OSWORD 7 and OSWORD 8 to use a different chip... Yes - see here for an implementation that sends SOUND commands to a MIDI interface: http://mdfs.net/Software/MIDI/ A while back, I used it with a home-made MIDI interface and a Yamaha k...
by RobC
Fri Feb 16, 2018 11:24 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

I was hoping that NuLA could control it and that a NuLA reset could be used to reset the frame, but I guess not. Unfortunately, all the sync stuff is controlled by the 6845. The Video ULA just outputs the serialised data and continues to do so unless told not to by the DISEN signal. I'll try to fin...
by RobC
Fri Feb 16, 2018 11:07 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

It's only interlace, but the user manually has to choose to swap the fields if they are the wrong way around unless some one has found a way to detect which field is showing. Rob, does NuLA know which field is showing/can it set it? I have a vague recollection that someone found that the timing of ...
by RobC
Thu Feb 15, 2018 9:38 pm
Forum: hardware
Topic: Music 5000 - sound generation
Replies: 12
Views: 403

Re: Music 5000 - sound generation

I wouldn't expect to see it used as a sound peripheral for a game. There a quote from Nick "Orlando" Pelling about using the Music 500 in Firetrack 2 in the Lost & Found section of the Stairway to Hell site. He basically says the same thing - it just takes up too much of the CPU's tim...
by RobC
Thu Feb 15, 2018 2:47 pm
Forum: hardware
Topic: Myelin's in-system updateable MegaROM for the BBC Master 128
Replies: 18
Views: 752

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

jgharston wrote: Just need somebody to unsolder my VULA and socket it.

I'll to do it if you're happy to cover P&P. Royal Mail charge £4.40 each way for 1st class/signed for if you just send the PCB in cardboard and bubble wrap...
by RobC
Thu Feb 15, 2018 12:10 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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!) If you search on 8bs for GLM PD disk 8, ...
by RobC
Thu Feb 15, 2018 6:48 am
Forum: hardware
Topic: Running DosPlus (version 2.1) with Raspberry Pi 80286 processor emulator on BBC master 128.
Replies: 33
Views: 1530

Re: Running DosPlus (version 2.1) with Raspberry Pi 80286 processor emulator on BBC master 128.

I have a CF/HD disk image that comes from an install I did from floppies onto my DC. Haven't tried using BeebSCSI yet so don't know whether it can use the same disk images (.dat) but I can send you a link to my disk image if you want. Also, if you've got ADFS explorer, you can browse files and see t...
by RobC
Wed Feb 14, 2018 11:58 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

Sorry - calling it "shadow screen memory" was misleading. According to this (and other sources I've found), the CPC can display screen data from any address in its 64KB RAM and use it for double buffering etc.: http://www.irespa.eu/daan/lib/howtoCPCemu.htm I need to think whether this is g...
by RobC
Wed Feb 14, 2018 8:43 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

Thanks Rich - I've only just started looking into it as I don't know too much about the CPC. The similarities between the hardware made me think that it's worth exploring. The Spectrum emulator already has a mechanism for timing host actions (e.g. border and sound) based on the number of tstates so ...
by RobC
Wed Feb 14, 2018 7:49 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

Thanks tricky - I'll give it a go. I notice that a lot of downloadable snapshot games are in .z80 format and not the .sna format used by SpectROM. Thanks for the tip Ken. I could add .z80 support if required as I only chose .SNA because I had a CD full of them - I think it came with the !Z80Em emula...
by RobC
Tue Feb 13, 2018 8:33 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

remember to set the sound volume to silent... Thanks tricky. Presumably this is the volume for tone generator 1 rather than the noise channel? It should be fairly easy for me to try this out so I'll give it a go in the next day or so. (I've just started looking at a CPC emulator so that's taking up...
by RobC
Tue Feb 13, 2018 7:18 pm
Forum: introduce yourself
Topic: new to BBC
Replies: 11
Views: 244

Re: new to BBC

Welcome.

I've managed to find an old link to the Windows MMBImager software via the Wayback machine:
https://web.archive.org/web/20161115035534/https://swhs.home.xs4all.nl/bbc/mmbeeb/windows.html

Not sure if there are later versions though...
by RobC
Tue Feb 13, 2018 1:42 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

Rob, have you tried using "periodic noise" with the frequency controlled by the sound channel for lower frequencies? Hi tricky. I haven't - could you explain how this would work as I'm not familiar with the concept? I've tried PCM with frequency set to the highest value and volume based o...
by RobC
Tue Feb 13, 2018 12:40 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

This is working pretty amazingly well Rob, very impressive Thanks - I'm really pleased with how well it works :D The true star is the Pi co-pro as it does all the heavy lifting. Even the audio sounds great. It works better in some games than others - the speech in Ghostbusters is intelligible but t...
by RobC
Mon Feb 12, 2018 10:17 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

Thanks for pointing that out Dave. Not sure how it got corrupted but it looks like the README file has overwritten part of the ROM image. It should be okay again now. (It's better to use the version from the Dropbox link as it fixes a couple of keyboard handling issues...) There are some SNA files a...
by RobC
Mon Feb 12, 2018 7:52 pm
Forum: upcoming and recent events & exhibitions
Topic: RISC OS SouthWest Show 2018 - Saturday 24th February, 2018
Replies: 2
Views: 298

Re: RISC OS SouthWest Show 2018 - Saturday 24th February, 2018

I took some Beebs along last year and could do the same again. The Beebs generated a bit of interest but it meant I didn't get to see as much of the show as I'd done in previous years... If there's enough interest, I could ask for a table again and have the Spectrum emulator running just to confuse ...
by RobC
Mon Feb 12, 2018 11:04 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 113
Views: 3436

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

I've updated the VideoNuLA support pack to document the new Spectrum and Thomson attribute modes and have added the latest version of the SpectROM emulator. It can be downloaded from Dropbox via the following link: https://tinyurl.com/y75cmrxe This corrects a couple of bugs in the keyboard handling ...
by RobC
Sat Feb 10, 2018 1:24 pm
Forum: hardware
Topic: Screen shadow memory
Replies: 18
Views: 555

Re: Screen shadow memory

I think the IntegraB board adds shadow RAM in a similar way to the B+ but I'm not sure there's anything that does it in the same way as the Master (i.e. having two banks available for display). I guess the connections to the 6845 are a problem or it would have been before. It would be a useful upgra...