Search found 922 matches

by kieranhj
Sun May 22, 2016 12:05 am
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

For purity we'd ideally want to setup a 60Hz IRQ, but I'm assuming that's tricky on a PAL system, so 100Hz is the nearest convenient timer interval above 60Hz (effectively oversampling the 60Hz original). For demos we favour speed over quality so trading off simpler play back timers with tunes slig...
by kieranhj
Sat May 21, 2016 11:56 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

There's also Julian's envelope compressor - this does a terrible job on those fast complex tunes (because there are more than 256 envelopes) but a really good job on some of the others I've come across. Attached is an example ice.vgm. It comes out at 19846 bytes Exo compressed in our raw format, but...
by kieranhj
Sat May 21, 2016 11:35 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

I've processed a few VGM tunes, quite a few aren't squeezing into 16Kb so we might need some more cunning plans soon. Shame about zlib cause that eats it for breakfast! In terms of a vanilla BBC music disk, in MODE 7 we'd have 25344 bytes for the tune assuming the player can be relocated lower down...
by kieranhj
Sat May 21, 2016 11:30 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Thanks Simon, just grabbed it and works a treat. :) How were you comparing the difference between 50Hz & 100Hz resampling? Using a PC vgm player I hope? I implemented 100Hz playback on the Beeb using Timer 1 (handles raw or vgm files.) Attached is a 50Hz and a 100Hz version of fluid.vgm for comparis...
by kieranhj
Sat May 21, 2016 3:51 pm
Forum: 8-bit acorn hardware
Topic: M128 Screen Corruption
Replies: 16
Views: 2477

Re: M128 Screen Corruption

Thanks for the suggestion - I will pick some up to test.
by kieranhj
Sat May 21, 2016 2:34 pm
Forum: 8-bit acorn hardware
Topic: Possessed Master.. help!
Replies: 4
Views: 889

Re: Possessed Master.. help!

I should also add that I have an internal 6502 2nd processor board mounted internally as well.

Bummed, I was really enjoying listening to those VGM tunes on real hardware for a change and playing Tricky's Frogger & Astroblaster. :(
by kieranhj
Sat May 21, 2016 2:26 pm
Forum: 8-bit acorn hardware
Topic: M128 Screen Corruption
Replies: 16
Views: 2477

Re: M128 Screen Corruption

Rather than being a ROM issue, i was wondering if anyone knew of any hardware issue that could be causing this? Serial Port controller / IC based issues etc? I've seen similar issues caused by CPU failure. Does the behaviour change when the Master warms up? I've just experienced similar problems wi...
by kieranhj
Sat May 21, 2016 2:19 pm
Forum: 8-bit acorn hardware
Topic: Possessed Master.. help!
Replies: 4
Views: 889

Possessed Master.. help!

Argh! I knew I shouldn't have yanked the Master Modem out of my machine. Now I am having an intermittent hardware fault. :( After a few minutes the screen starts filling up with garbage, random characters get entered into the keyboard, random noise starts coming out of the speaker, video signal will...
by kieranhj
Sat May 21, 2016 1:44 pm
Forum: for sale / freebies
Topic: Beebug Master Modem - free to good home!
Replies: 1
Views: 624

Beebug Master Modem - free to good home!

I finally managed to extract the Master Modem from my Master. Would anyone like this for the price of postage & packaging?

I have no way of testing it and hopefully didn't damage the cable during removal. I have the manual as well. Send me a PM.

Image
by kieranhj
Sat May 21, 2016 12:27 am
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

The final one from the disk - Samurai in Tsutenkaku - is about 2kb too large for me to fit it into the player without modification but it should play fine in theory. OK, so I managed to squeeze it into memory on Master only by fiddling with the compression settings and by using the screen buffer as...
by kieranhj
Sat May 21, 2016 12:17 am
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

It's just a hunch, but I have a feeling that some of these would sound better at 60Hz or 100Hz... I'm a fussy listener and I'm sure I can detect a few flaws in the playback of the busier tunes when quantized to 50hz. Wasn't there a built-in 100Hz IRQ on the beeb? I seem to recall the BASIC sound en...
by kieranhj
Sat May 21, 2016 12:03 am
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

And because I'm feeling kind (read: my wife isn't here to tell me to go to bed) - here are four more. :) I should state that although these playback at the right speed they have not been retuned for the Beeb so might sound a little funky. The final one from the disk - Samurai in Tsutenkaku - is abou...
by kieranhj
Fri May 20, 2016 11:48 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Ooh, if it's possible to 'uprate' VGM conversions to 60hz, could you take a look at these Master System/Ninja Gaiden tracks that Sarah converted a number of years back? As I'd love to hear these played at full tempo on a Beeb (well, BBC Master!) :) Btw, what is the origin of the track contained wit...
by kieranhj
Fri May 20, 2016 10:48 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Added bin file containing the raw data version of fluid vgm for your experimentation Kieran - hopefully formatted correctly! (not tested) - quantized to 50Hz Cool. I changed the player quickly but I think the data is missing waits when there is no sound. Attached is the player ssd but you can hear ...
by kieranhj
Fri May 20, 2016 8:14 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

OK, now we're motoring. :) Attached is v4 of my player that runs at 50Hz only with Exomiser crunched VGM files. I had a penny-dropping moment after your post Simon so this handles wait times of any lengths it just only sends the sound data every 20ms. This means that 60Hz NTSC files send two lots of...
by kieranhj
Fri May 20, 2016 4:56 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Thanks Simon. VGM also supports looping points but given that neither player I have at the moment does we can worry about that later!

I'll look out for your byte stream file. :)
by kieranhj
Fri May 20, 2016 1:33 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Nice work Simon! This sounds great. I will dust off the vgmplay code tonight and rewrite to only handle fixed 50Hz timesteps. First pass will be to handle existing VGM format and just calculate the nearest multiple of 20ms for all wait commands that are not 50Hz. It should make things a lot simpler....
by kieranhj
Thu May 19, 2016 8:01 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Here's a zip with some more converted VGM's for you to play with. All of the beeb ones are resampled to 50Hz update intervals. Bear in mind my conversion script still has a few snags in it, and also some of the tunes need faster than 50Hz updates to sound ok. Mission is particularly monstrous in it...
by kieranhj
Thu May 19, 2016 7:00 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Would using 8 bit indices, but with a larger granularity than 1 byte work, failing that, a table of 16bit indices indexed by an 8 bit value. I don't really remember the format, so I might be talking rubbish! I realised I was being an idiot - I don't need full 16-bit values for indices, an extra 2-b...
by kieranhj
Wed May 18, 2016 9:15 pm
Forum: stardot FORUM
Topic: Forum Software Upgrade
Replies: 92
Views: 11160

Re: Forum Software Upgrade

Don't worry, not important. I can repost. Thanks.
by kieranhj
Wed May 18, 2016 1:56 pm
Forum: stardot FORUM
Topic: Forum Software Upgrade
Replies: 92
Views: 11160

Re: Forum Software Upgrade

I lost a PM and a post from late last night (around 11pm UK time) BTW. Not sure if this was upgrade related?
by kieranhj
Tue May 17, 2016 8:11 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Time to form a new demo crew maybe! :) Demo crew you say? ;) So I worked out what was happening with the vgms that produce "invalid" data from the vgmproc convertor - the data is valid, there's just too much of it! To get around this requires changing the player to handle 16-bit indices for the env...
by kieranhj
Mon May 16, 2016 11:19 pm
Forum: new ideas wishlist & general chat
Topic: what should i write next?
Replies: 313
Views: 33660

Re: what should i write next?

Interesting idea, I'll have to track down the source. Main problem I'm guessing would be the limit on how many vectors a Beeb can rasterise in 20ms, not a lot is the likely answer. The original arcade machine being a vector display meant these were all a fixed cost I'm guessing (curious to look up ...
by kieranhj
Mon May 16, 2016 10:43 pm
Forum: new ideas wishlist & general chat
Topic: what should i write next?
Replies: 313
Views: 33660

Re: what should i write next?

1. Tempest - The original arcade machine was 6502 based and the source code was only 8k in size. Perhaps you could do a Mode 1 version with 8 colours? or even a hi-res Mode 0 version with *some* colours. This would be a good opportunity for you to experiment with a vector scan type routine for the ...
by kieranhj
Mon May 16, 2016 9:04 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

I managed to get puppeh's (Julian) vgmproc convertor working and ported his player to BeebAsm (since I can't get his pasta assembler built on Windows.) See (or rather hear) the attached ssd for the result using chris_beeb.vgm. This player has advantages that it happily runs on the vsync event and ha...
by kieranhj
Mon May 16, 2016 1:49 pm
Forum: other vintage hardware, software and languages
Topic: Monster 6502
Replies: 3
Views: 1010

Monster 6502

http://monster6502.com/ The MOnSter 6502 A new dis-integrated circuit project to make a complete, working transistor-scale replica of the classic MOS 6502 microprocessor. We'll be showing off our progress at the 2016 Bay Area Maker Faire! Credits The MOnSter 6502 is a work in progress, designed by ...
by kieranhj
Sun May 15, 2016 7:41 pm
Forum: introduce yourself
Topic: Hello peeps
Replies: 15
Views: 2065

Re: Hello peeps

simonm wrote:Friendly bunch! Hi all.
@Kieran - not ignoring your PM mate, forum has that feature disabled for me atm.
No worries. You probably need min # posts?
by kieranhj
Fri May 13, 2016 7:05 pm
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Your converted VGM tune sounds really nice, not pitchy at all! (Although I guess I don't have the original to compare with.) I haven't had much luck with Julian's VGM player. :( The optimiser / compiler works on some files but produces invalid output with others (I suspect it was tuned for the music...
by kieranhj
Thu May 12, 2016 7:05 am
Forum: new projects and releases: demoscene
Topic: Beeb MOD Player
Replies: 72
Views: 8037

Re: Beeb MOD Player

Look forward to hearing the results! I'm halfway through porting Julian's VGM player source to BeebAsm as I can't get his pasta assembler to build on my Windows machine (he's a Linux guy it would seem.) The OCAML parser / compressor appears to work fine with other VGM files, I just can't test what t...

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