Search found 1057 matches

by dominicbeesley
Mon Jul 06, 2020 1:24 pm
Forum: acorn & bbc micro user group (abug) events
Topic: All-day 'Virtual' Acorn session #5, Saturday 4th July 2020, 9am - 10pm
Replies: 61
Views: 1950

Re: All-day 'Virtual' Acorn session #5, Saturday 4th July 2020, 9am - 10pm

I look forward to watching the videos, I'm afraid this one completely passed me by, though this time I couldn't attend but I don't want to miss any future events. Is there any way we could easily make a single announcement thread for these, those interested could then subscribe to that thread and no...
by dominicbeesley
Sun Jul 05, 2020 6:47 pm
Forum: acorn atom and acorn system series
Topic: Connect a 80287 to a 6502 computer?
Replies: 12
Views: 365

Re: Connect a 80287 to a 6502 computer?

I will follow with interest - I have been looking at something like this but I didn't think of the intel chips!

D
by dominicbeesley
Thu Jul 02, 2020 12:21 pm
Forum: 8-bit acorn software: other
Topic: Why was BBC BASIC so fast?
Replies: 35
Views: 1038

Re: Why was BBC BASIC so fast?

the Basic is tokenised and expressions are converted to an RPN format and partially compiled programs into machine code before running them Neither of these are true as far as I'm aware from doing a line-by-line port the expressions are evaluated in the order they are written (by a quite clever and...
by dominicbeesley
Sat Jun 27, 2020 5:50 pm
Forum: 8-bit acorn hardware
Topic: BBC Buggy LDR
Replies: 1
Views: 144

Re: BBC Buggy LDR

Just seen this - I would buy a handful from ebay GL5506 looks like a likely candidate, you don't say how much light but I would have thought they are unlikely to be too critical?

D
by dominicbeesley
Sun Jun 21, 2020 8:39 pm
Forum: programming
Topic: Which 8 bit computers could run BBC BASIC?
Replies: 25
Views: 878

Re: Which 8 bit computers could run BBC BASIC?

My 6809 port comes out like this: 20200621_203331.jpg And 6309 a touch quicker 20200621_203603.jpg YMMV especially if you're doing a lot of trig! Sorry for the photo quality EDIT: I forgot to disable interrupts so these are a bit slower than they should be. I've been told to sit down and stop playin...
by dominicbeesley
Fri Jun 19, 2020 11:56 am
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

Cool, I've not had a look at the trace thing yet - it probably doesn't quite work as it stands but shouldn't take too much to fix up - I'm still using Dave's decode6502. This evening or weekend I'll get the trace thing tested and try the suggestions (registers first, tab separators) and continue to ...
by dominicbeesley
Fri Jun 19, 2020 12:10 am
Forum: 8-bit acorn hardware
Topic: A blitter for the beeb?
Replies: 129
Views: 14641

Re: A blitter for the beeb?

That's pretty much the idea. I've got something very basic working this evening and had captain pugwash playing with sampled pipes. I've got some issues with clicks when samples stop and start but I'm not sure if that is down to the emulator I'm working in but we'll find out when I try it on real ha...
by dominicbeesley
Fri Jun 19, 2020 12:07 am
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

Thanks Dominic,

I'll see if I can get that installed at least on my Linux machine. I'm not sure that the mingw/msys has that option though.

Coeus, I've fixed a couple more things and merged in the vdfs root in config file change too.

D
by dominicbeesley
Thu Jun 18, 2020 11:03 pm
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

PS: It wasn't all git, I had missed a couple of #include lines that probably caused a lot of the errors and warnings that you were getting.

What version of gcc are you on? It seems a lot stricter than any of mine

D
by dominicbeesley
Thu Jun 18, 2020 10:07 pm
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

Cool, I'll have a look at that truncation thing - at least it didn't overrun! I'll keep working away at it, it is certainly becoming more and more useful. Do you have any objection to me changing the debugger command parsing a little. At present it is a bit promiscuous in the way it handles commands...
by dominicbeesley
Thu Jun 18, 2020 3:18 pm
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

Well, I found some things weren't right here (which I've pushed to the paula_1m branch) but it still doesn't explain the differences in outcome - what version of gcc are you using and I'll try and set up the same here. I had a look and I couldn't find any const cpu_debug_t's anywhere. I've just got ...
by dominicbeesley
Thu Jun 18, 2020 9:47 am
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

That looks seriously broken, which it isn't here - I think there is something odd going on here with git. It would be good if, instead of doing a pull, you could go to https://github.com/dominicbeesley/b-em/tree/paula_1m (that's the paula_1m branch - that's the most up to date) and do a download as ...
by dominicbeesley
Wed Jun 17, 2020 10:14 pm
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

I've done some more work today and I think I've unborked most of my mistakes. I did get a bit carried away with fixing compiler warnings, if you don't like the scattering of explicit casts everywhere let me know and I can take them all back out. I'm actually using it in anger now and I've already sp...
by dominicbeesley
Wed Jun 17, 2020 4:17 pm
Forum: 8-bit acorn hardware
Topic: A blitter for the beeb?
Replies: 129
Views: 14641

Re: A blitter for the beeb?

Thanks both for the interest. jregel, everything runs at 8MHz at present though I might look at pushing that to 16 to allow uncontended access between the cpu and chipset. At present there is (an over-complicated) arbitration and bus switching arrangement which I keep meaning to simplify. The "bus" ...
by dominicbeesley
Wed Jun 17, 2020 11:04 am
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

Yeah, the map/hash thing is very much thrown together - though it really doesn't need to be that quick, the symbols are only looked up when doing interactive stuff not when the emulation is actually running. I'll look at adding another map (I think they're usually binary or red-black trees) so searc...
by dominicbeesley
Tue Jun 16, 2020 11:15 pm
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

I've not forgotten this, I made a start but there's still a way to go - my branch is at https://github.com/dominicbeesley/b-em/tree/coeus-symbols - it's not really ready to pull yet, again real life got in the way today. The symbol table itself is pretty rough at the moment - I'll replace it with so...
by dominicbeesley
Tue Jun 16, 2020 9:09 am
Forum: 8-bit acorn hardware
Topic: A/B 6502 switcher project
Replies: 32
Views: 724

Re: Random hardware thought

I'm a big fan of the 74cb3t parts but they won't do the TTL to CMOS level conversion that is needed here.

I'd look at maybe a few 74HCT244 buffers?

D
by dominicbeesley
Mon Jun 15, 2020 10:07 pm
Forum: 8-bit acorn hardware
Topic: A/B 6502 switcher project
Replies: 32
Views: 724

Re: Random hardware thought

I could have sworn I replied to this earlier today but I must have closed the browser window! I'll briefly cover some of the points again. It the DBE input on some of the vesions of the 65c02 could be a help but there would still need to be some isolation of the other signals. Some quick notes of th...
by dominicbeesley
Mon Jun 15, 2020 7:56 pm
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

I made a start on this today but had to deal with some other stuff - I'll report back tomorrow

D
by dominicbeesley
Mon Jun 15, 2020 9:44 am
Forum: 8-bit acorn emulators
Topic: Threads and emulators
Replies: 38
Views: 1174

Re: Threads and emulators

Thanks Tom, that is a slightly different approach to what I was thinking but I'll try and get a look. I'm going to look at the threading stuff that Coeus has on a branch for b-em and I'll try and get my head into b2 at some point this week - it's another emulator I ought to try!

D
by dominicbeesley
Mon Jun 15, 2020 8:56 am
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

Thanks for all this.

I'll have a look where you're up to today and try and get time to put in the symbol table....

I'll have a look at trace too - I'm guessing that all the symbol goodness will come through in trace for free?
by dominicbeesley
Sun Jun 14, 2020 7:28 pm
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

Cool, most of my build stuff for assembler is quite unix-y (or cygwin-y). I use a mixture of ca65 and beebasm and I've got scripts that take the symbols from either and turn them into NoICE commands so something similar would be a big help. NoICE has the ability for a paging/register register and wi...
by dominicbeesley
Sun Jun 14, 2020 12:33 pm
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

Great, I'd not spotted exec but it is there in the help for debug so I don't know how I missed it. As to symbols I'd prefer a simple command to add symbols something like: sym[bol] [<romno>:]<address> name rather than a specific format, conversion from ca65, beebAsm etc could then be simple scripts ...
by dominicbeesley
Sat Jun 13, 2020 12:02 pm
Forum: 8-bit acorn emulators
Topic: Threads and emulators
Replies: 38
Views: 1174

Re: Threads and emulators

Thanks Coeus,

Yes, how are you measuring cpu? - it's not helped by different utilities having a different definition of "core".



D
by dominicbeesley
Sat Jun 13, 2020 11:59 am
Forum: 8-bit acorn emulators
Topic: B-Em
Replies: 498
Views: 43828

Re: B-Em

I've added a pull-request to GitHub which contains a few fixes for things I've been tripping over recently 1) Alt-tab away from b-em causes alt key to stick On Windows machines* Alt-tabbing to/from b-em often caused it to get the alt-key stuck down and so the next press of enter attempted to go to f...
by dominicbeesley
Thu Jun 11, 2020 10:37 pm
Forum: 8-bit acorn emulators
Topic: Threads and emulators
Replies: 38
Views: 1174

Re: Threads and emulators

There's certainly no criticism of b-em from me - nor is it slow - well not the mainline version: my fork is definitely marginal but that is due to it being more of a timing simulation so coded for accuracy and clarity of my blitter stuff rather than for speed. As to the palette and graphics getting ...
by dominicbeesley
Thu Jun 11, 2020 3:05 pm
Forum: 8-bit acorn emulators
Topic: Threads and emulators
Replies: 38
Views: 1174

Re: Threads and emulators

Thanks Thomas, for your information about CLK, I'd not come across your emulator before - there are a lot around. I will have to try it out it looks to have an interesting approach! I'll try and get a look next week at it - when the child is back at school and I get some thinking time. Did you use a...
by dominicbeesley
Thu Jun 11, 2020 2:00 am
Forum: 8-bit acorn emulators
Topic: Threads and emulators
Replies: 38
Views: 1174

Re: Threads and emulators

It's not to my taste but I think it is a "valid" part of the emulator experience to have something that looks and feels as much like the "found in a skip" telly fondly remembered. Personally I quite quickly bore of such gimmicks but they do have their place? BITD I had to try and code through the ra...
by dominicbeesley
Thu Jun 11, 2020 12:05 am
Forum: 8-bit acorn emulators
Topic: Threads and emulators
Replies: 38
Views: 1174

Re: Threads and emulators

Thanks Matt, Good point about the IRQ(s) (Only one I think needs to be considered, VSync?) though if there is a mirrored CRTC (which is what I envisaged) on both threads would do it: one does the raster magic on the "graphics side" the other just ticks its registers and does the interrupt. I don't t...

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