Search found 130 matches

by scarybeasts
Tue Aug 20, 2019 5:26 am
Forum: upcoming and recent events & exhibitions
Topic: Acorn World and ABUG meetup, Cambridge 20-22nd September 2019
Replies: 95
Views: 3836

Re: Acorn World and ABUG meetup, Cambridge 20-22nd September 2019

Moderators note: The archive request posts have been moved to a separate thread " Cambridge Sept 2019 archiving thread ". So can you please post anything related to archiving, scanning or similar in that thread rather than here, in this thread. Thanks Mark I'll be bringing some surplus software to ...
by scarybeasts
Sat Aug 17, 2019 12:34 am
Forum: emulators
Topic: Uridium and other games not working on JSBeeb
Replies: 30
Views: 497

Re: Uridium and other games not working on JSBeeb

Hi Chris, Great work so far =D> The issue that springs to my mind is the MODE 7 emulation. I don't think any emulator gets this exactly right. It could be fun to go on a spelunking mission to find teletext corner cases. But in the short term, I'd prefer to drive work off a list of known issues with...
by scarybeasts
Sat Aug 17, 2019 12:32 am
Forum: emulators
Topic: Uridium and other games not working on JSBeeb
Replies: 30
Views: 497

Re: Uridium and other games not working on JSBeeb

lurkio wrote:
Fri Aug 16, 2019 10:01 am
Hopefully the complete lack of sound in Safari on macOS can also be fixed. There seems to be a potential solution here:
:idea:
Ok, I'll sort this out.


Cheers
Chris
by scarybeasts
Fri Aug 16, 2019 8:10 am
Forum: emulators
Topic: Uridium and other games not working on JSBeeb
Replies: 30
Views: 497

Re: Uridium and other games not working on JSBeeb

Chris/scarybeasts has been busy fixing bugs in JSBeeb, and the new version of JSBeeb is now live at godbolt.org: https://bbc.godbolt.org I'd encourage everyone to test it with loads of different .SSD and .DSD disc-images to see how robust it is. Seems pretty good so far! Please do test! My main hop...
by scarybeasts
Sat Aug 10, 2019 9:31 pm
Forum: wanted
Topic: Wanted: map and clues sheet for BBC Exile
Replies: 6
Views: 252

Re: Wanted: map and clues sheet for BBC Exile

billcarr2005 wrote:
Sat Aug 10, 2019 2:20 pm
The pages have gone a lovely shade of off-white over the years...
That's the ones. Are these available for sale, trade (I have various Exile and other spare bits), jsbeeb patches / fixes, charitable donation? :)


Cheers
Chris
by scarybeasts
Sat Aug 10, 2019 9:55 am
Forum: upcoming and recent events & exhibitions
Topic: Acorn World and ABUG meetup, Cambridge 20-22nd September 2019
Replies: 95
Views: 3836

Re: Acorn World and ABUG meetup, Cambridge 20-22nd September 2019

jbnbeeb wrote:
Sat Aug 10, 2019 9:35 am
Can I assume you will be along for the entire weekend?
Yes! And oops, sorry for not adhering to the bolded instruction at the start of the thread :)


Cheers
Chris
by scarybeasts
Sat Aug 10, 2019 7:09 am
Forum: upcoming and recent events & exhibitions
Topic: Acorn World and ABUG meetup, Cambridge 20-22nd September 2019
Replies: 95
Views: 3836

Re: Acorn World and ABUG meetup, Cambridge 20-22nd September 2019

Hi,

Can you put me down as a no-kitter?
I live in the US these days but this is too good to miss :)


Cheers
Chris
by scarybeasts
Fri Aug 09, 2019 10:45 am
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

Re: VIA port pin level behavior differences -- tests

tom_seddon wrote:
Fri Aug 09, 2019 12:19 am
Looks like it can pull the pin low if the VIA is outputting 1, but it can't pull (push?) it high if the VIA is outputting 0.
Excellent, so the data sheet was telling the truth all along. Great to have it confirmed via a real test.


Cheers
Chris
by scarybeasts
Thu Aug 08, 2019 1:46 am
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

Re: VIA port pin level behavior differences -- tests

I've now got a test that reads the RTC registers and prints them on screen. If AS=1 the whole time, the value read is always FF, suggesting that the RTC is indeed not driving the bus. FF is what my Master gives when reading the slow databus with all devices disabled. (And this is also true when jus...
by scarybeasts
Wed Aug 07, 2019 12:05 pm
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

Re: VIA port pin level behavior differences -- tests

(I noticed while looking at this that b2 doesn't quite get RTC reads right, as it treats DS as a strobe in read mode rather than as a flag: https://github.com/tom-seddon/b2/issues/51) I wonder if "fixing" that would actually break b2? The current b2 code appears to look for a DS transition and then...
by scarybeasts
Tue Aug 06, 2019 11:55 pm
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

Re: VIA port pin level behavior differences -- tests

I doubt if emulators need to this. IMHO there is no emulated hardware that pulls a "high" output pin to "low". So reading back ORA or ORB seems sufficient to me. Thanks Roland and Mark for the resources and answers! It's great to have hardware and electrical engineering experts here. I have one fol...
by scarybeasts
Tue Aug 06, 2019 12:32 pm
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

Re: VIA port pin level behavior differences -- tests

So while the RTC will become enabled, and in read mode, it won't actually attempt to drive the bus. Thinking about this some more, there would be some super interesting non-RTC tests that could shed some light into bus contention, if we wanted to pin this down: 1) Compete keyboard and sound. Enable...
by scarybeasts
Tue Aug 06, 2019 7:53 am
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

Re: VIA port pin level behavior differences -- tests

I didn't realise you weren't using the latest, so I tried the tests on latest b2, and it looks like they're all now accidentally fixed, as the results are now a lot better :) Sorry about that, I'll update. The Uridium disc image works fine on my real Master, and on latest b2 in M128 mode. You're ri...
by scarybeasts
Tue Aug 06, 2019 4:31 am
Forum: wanted
Topic: Wanted: map and clues sheet for BBC Exile
Replies: 6
Views: 252

Re: Wanted: map and clues sheet for BBC Exile

ISTR that Impact posters produced a printed map and hints that were possibly obfuscated... it's possible i've got that somewhere, if it's not already been uploaded anywhere... Ah, I found a good reference showing the official Superior Software map + clues, on these very forums :) See pictures: http...
by scarybeasts
Mon Aug 05, 2019 10:25 pm
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

Re: VIA port pin level behavior differences -- tests

I remember there's a difference in handling between port A and port B. Don't remember the details exactly, but it was to do with where the input bits come from. I remember noticing it in the datasheet, thinking I should implement it in jsbeeb (because B-Em didn't make the distinction), and then pro...
by scarybeasts
Mon Aug 05, 2019 10:19 pm
Forum: wanted
Topic: Wanted: map and clues sheet for BBC Exile
Replies: 6
Views: 252

Re: Wanted: map and clues sheet for BBC Exile

Hi, All Exile releases were supposed to come with two blue mail-in cards. For an image of what a complete set looks like, try: https://www.picclickimg.com/d/l400/pict/163029375247_/Exile-Acornsoft-Acorn-Electron-tape-cassette-game-Vintage.jpg (There was a problem where a ton of boxes were accidental...
by scarybeasts
Mon Aug 05, 2019 1:39 am
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

Re: VIA port pin level behavior differences -- tests

Hi Tom, Thanks for collaborating on this! These results suggest to me that the jsbeeb / b-em style of handling port pins may be the correct one, although it seems a pretty nuanced area so I'm not 100% sure. I think I may have found a manifestation of where it can go wrong in real software: when I up...
by scarybeasts
Sun Aug 04, 2019 9:53 pm
Forum: wanted
Topic: Wanted: map and clues sheet for BBC Exile
Replies: 6
Views: 252

Wanted: map and clues sheet for BBC Exile

Hi,

Exile came with a little blue mail-in card you could send off to get a printed map and clues.

Does anyone have a spare printed map and clues kicking around for sale or swap? I have a bunch of spare Exile stuff to trade if that is of interest.


Cheers
Chris
by scarybeasts
Sun Aug 04, 2019 12:26 pm
Forum: emulators
Topic: VIA port pin level behavior differences -- tests
Replies: 20
Views: 585

VIA port pin level behavior differences -- tests

Hi, While trying to fix a jsbeeb bug, I've come across area of interesting disagreement between emulators, relating to how the VIA chips handle interesting input vs. output pin situations. In this instance, I've been using b2 as an inspiration (thanks Tom!) which appears to make a more robust effort...
by scarybeasts
Sat Aug 03, 2019 10:37 am
Forum: emulators
Topic: Uridium and other games not working on JSBeeb
Replies: 30
Views: 497

Re: Detecting BeebEm

At least we understand what is wrong with the dodgy versions and why some of the emulators crash on load. How come the "broken" version of the game apparently works without any problems on a real Beeb then? :?: Emulators tend to have low resolution of keyboard polling and often the keyboard is poll...
by scarybeasts
Sat Aug 03, 2019 9:29 am
Forum: bbcmicro.co.uk
Topic: Uridium ssd file not found
Replies: 23
Views: 2229

Re: Uridium ssd file not found

Probably best to ignore the file in my last post, see the version here that works correctly:

viewtopic.php?f=51&t=13967&p=184720#p184671
by scarybeasts
Sat Aug 03, 2019 9:22 am
Forum: emulators
Topic: Uridium and other games not working on JSBeeb
Replies: 30
Views: 497

Re: Detecting BeebEm

Although, as discussed in the post above, you've fixed a version which is broken in other ways :roll: Oh, unbelievable! I hadn't noticed the variant you're referring to. sha256sum: 4e5f5aba3981978856ada91f1831ebb78faae0ea0a6bf59a7729de52e6c30adc This one is doubly safe already. It has interrupts di...
by scarybeasts
Sat Aug 03, 2019 6:29 am
Forum: emulators
Topic: Uridium and other games not working on JSBeeb
Replies: 30
Views: 497

Re: Detecting BeebEm

It's kind of ironic that I am now being asked to amend a copy of game to work on a newer emulator rather than the author of the emulator being asked to upgrade the emulator to run the game as BeenEm and others do. But I will do it as I believe in having the best version of all games available for a...
by scarybeasts
Sat Aug 03, 2019 5:49 am
Forum: bbcmicro.co.uk
Topic: Uridium ssd file not found
Replies: 23
Views: 2229

Re: Uridium ssd file not found

Here is what is going on with Uridium. This applies to the STH version and the bbcmicro.co.uk version. The latter makes a better attempt to avoid the problem, but still does not avoid the problem. The crux is that execution of the game loader arrives at &6F00, with IRQs enabled. It proceeds to set u...
by scarybeasts
Thu Aug 01, 2019 3:57 am
Forum: emulators
Topic: Puff and DFS-0.9 vs. DFS-1.2
Replies: 14
Views: 374

Re: Puff and DFS-0.9 vs. DFS-1.2

Hi Chris, I can't check this disc as I am away at the moment but I think I did this tape to disc transfer for bbcmicro.co.uk. I am not an expert, but as far as I am aware the DFS workspace between &1100 to &1900 should be OK to use as long as the program just loads and runs, and does not use OPENIN...
by scarybeasts
Wed Jul 31, 2019 4:22 am
Forum: emulators
Topic: Puff and DFS-0.9 vs. DFS-1.2
Replies: 14
Views: 374

Re: Puff and DFS-0.9 vs. DFS-1.2

It appears to be a DFS-0.9 (fails) vs. DFS-1.2 (works) issue. Actually, investigating a bit more, it looks like a problem with the Puff disc. In an effort to work around a "No room" out-of-memory type error, the loader sets page to &1700. This is going to trample some of the DFS work space, no? I t...
by scarybeasts
Wed Jul 31, 2019 2:51 am
Forum: emulators
Topic: Puff and DFS-0.9 vs. DFS-1.2
Replies: 14
Views: 374

Puff and DFS-0.9 vs. DFS-1.2

Hi, I was just debugging why Puff doesn't work in jsbeeb default mode (vanilla beeb) but does work in BeebEm default mode: http://bbcmicro.co.uk/game.php?id=2195 It appears to be a DFS-0.9 (fails) vs. DFS-1.2 (works) issue. Two questions: - Is anyone able to test Puff loading from a real beeb using ...
by scarybeasts
Tue Jul 30, 2019 9:54 am
Forum: emulators
Topic: Sampled sound on the sn76489 -- tests
Replies: 34
Views: 951

Re: Sampled sound on the sn76489 -- tests

That's great work Tom. Seems as long as the WE bit is in a known state, data can be pumped to the SN chip as fast as it can handle it. =D> Yeah, I'm pretty excited by this. That's a decent CPU cycle budget to throw different samples (or different rates) to all 3 tone channels. Or synthesize SID-lik...
by scarybeasts
Mon Jul 29, 2019 9:42 am
Forum: emulators
Topic: Sampled sound on the sn76489 -- tests
Replies: 34
Views: 951

Re: Sampled sound on the sn76489 -- tests

are you describing how it behaves on real hardware or are you asking for testing? (I have no idea if you have a real beeb or not I've run the test on real hardware (Master, SN76494AN), and it does produce the expected sound. I haven't done (not even really thought very hard about how to do...) any ...
by scarybeasts
Mon Jul 29, 2019 1:25 am
Forum: emulators
Topic: Sampled sound on the sn76489 -- tests
Replies: 34
Views: 951

Re: Sampled sound on the sn76489 -- tests

Fixed code is below. It just plays two alternating tones on channel 1 with ~WE=0 the whole time. I assume it'll just re-execute the command on every cycle if you leave it in this state? - safe enough for tone/volume, but you could I suppose end up with it resetting the noise shift register on every...