Search found 17 matches

by ComanderJameson
Tue Apr 29, 2014 6:44 pm
Forum: emulators
Topic: jsbeeb - a Javascript emulator
Replies: 153
Views: 19470

Re: jsbeeb - a Javascript emulator

Hey I've seen a lot worse! Nope, it emulates just a bog standard BBC Micro. Frogman runs fine no matter which filing system is installed ADFS, Watford. I wonder what the difference is? Now I'd like to get hold of some disc images with different encryption and see how it handles it. Any idea where I ...
by ComanderJameson
Tue Apr 29, 2014 5:55 pm
Forum: emulators
Topic: Frogman Encryption
Replies: 7
Views: 1311

Re: Frogman Encryption

This is now fixed in VBeeb. However, I still need to look at addressing modes other than absolute and work out their interaction in terms of timings.
by ComanderJameson
Tue Apr 29, 2014 5:53 pm
Forum: emulators
Topic: jsbeeb - a Javascript emulator
Replies: 153
Views: 19470

Re: jsbeeb - a Javascript emulator

Once I ironed out the instruction timings with the VIAs, Frogman runs just fine on both a standard Beeb and VBeeb emulator.
by ComanderJameson
Sat Apr 19, 2014 6:57 pm
Forum: emulators
Topic: Frogman Encryption
Replies: 7
Views: 1311

Re: Frogman Encryption

Thanks all. The penny finally dropped. I think I've got it right. The first time (for example): STA &FE64 executes, it may take 5 or 6 cycles (depending on where the 2MHz clock is). But because of the variable number of cycles, the effect is to sync the start of the next instruction to the 1MHz cloc...
by ComanderJameson
Sat Apr 19, 2014 10:27 am
Forum: emulators
Topic: Frogman Encryption
Replies: 7
Views: 1311

Re: Frogman Encryption

Thanks for that. I feel the penny dropping. But what is the 1MHz access (clock) pegged to? Rationally, it seems like it must be relative to the 2Mhz clock. If that's the case then the number of cycles for EOR &FE64, could either be 6 or 5 depending on whether it starts on an even or odd tick respect...
by ComanderJameson
Thu Apr 17, 2014 2:13 pm
Forum: emulators
Topic: Frogman Encryption
Replies: 7
Views: 1311

Frogman Encryption

I thought I'd start a new thread. So. I've been looking into getting VBeeb to run the Frogman SSD. Timings are improved so it manages to run more code. But, I'm stuck. This example illustrates the point (run on a real Beeb): 10 P%=&C00 20 [ 30 SEI 40 LDA #&B2 50 STA &FE64 60 STA &FE65 70 LDY #&20 80...
by ComanderJameson
Thu Apr 10, 2014 3:16 pm
Forum: emulators
Topic: jsbeeb - a Javascript emulator
Replies: 153
Views: 19470

Re: jsbeeb - a Javascript emulator

See my earlier post: New Beeb Emulator. Mine crashes out to Basic after selecting the number of players. I tally up clock cycles per machine instruction, so VIAs, IRQs etc only get updated after each instruction has finished executing. I've tried every game under the sun, so the technique seems soun...
by ComanderJameson
Thu Apr 10, 2014 8:50 am
Forum: emulators
Topic: jsbeeb - a Javascript emulator
Replies: 153
Views: 19470

Re: jsbeeb - a Javascript emulator

Very nice work indeed!

Interestingly, I can't get Frogman to work in my emulator either. But it baulks earlier than JSBeeb. Does it use undocumented op-codes? I'll see if I can get it to work, I like a challenge!
by ComanderJameson
Thu Jan 16, 2014 4:02 pm
Forum: emulators
Topic: VBeeb
Replies: 8
Views: 2123

Re: VBeeb

A bit late, but this is now at:

http://guille-phillips.co.uk/vbeeb/
by ComanderJameson
Mon Oct 14, 2013 9:25 am
Forum: emulators
Topic: New Beeb Emulator
Replies: 17
Views: 2361

Re: New Beeb Emulator

Nice. Thanks for looking at it. Hopefully, it will give me the impetus to keep working on it!
by ComanderJameson
Fri Oct 11, 2013 2:45 pm
Forum: emulators
Topic: New Beeb Emulator
Replies: 17
Views: 2361

Re: New Beeb Emulator

it was the one in your Cassettes folder, being GreedyDwarf_B.uef Erm... :oops: I've done a new release with these fixes in. So should be a bit more useable. The '53' error I don't get in Win7 when I load from tape, but that's a file permissions error. Strange since nothing is being written to. I wo...
by ComanderJameson
Thu Oct 10, 2013 8:53 am
Forum: emulators
Topic: New Beeb Emulator
Replies: 17
Views: 2361

Re: New Beeb Emulator

Splendid. Thanks for the feedback. Hadn't tried it on Win8, so it's nice to know it works. DirectX is used for the sound, but I have no solution to make it work on Win7/8 at the moment, which is a shame. Hence the message on starting up. I know that Watford DFS works, which I prefer. Not sure I ever...
by ComanderJameson
Wed Oct 09, 2013 2:37 pm
Forum: emulators
Topic: New Beeb Emulator
Replies: 17
Views: 2361

Re: New Beeb Emulator

You are quite right Prime/Phill, I stand corrected.

Hello Roland! Sorry, thanks, I was joking. I do know what Linux is, I've just never really made friends with it. Maybe there's hope for me yet?

Guille.
by ComanderJameson
Wed Oct 09, 2013 10:08 am
Forum: emulators
Topic: New Beeb Emulator
Replies: 17
Views: 2361

Re: New Beeb Emulator

Linux... what's that? Classic VB, I only use modern stuff at work. I usually tinker with the emulator in a VM running XP, it gives me a certain geeky pleasure to run an emulator in an emulator, but that's just me :D
by ComanderJameson
Wed Oct 09, 2013 8:56 am
Forum: emulators
Topic: New Beeb Emulator
Replies: 17
Views: 2361

New Beeb Emulator

Hi all, I thought I would punt my new Beeb emulator, which is available at: http://guille-phillips.co.uk/vbeeb/ It is very much a labour of love so be gentle! Saying that, all comments and suggestions are most gratefully received. It's entirely written in old style Visual Basic (since I'm a masochis...
by ComanderJameson
Wed Oct 09, 2013 8:40 am
Forum: introduce yourself
Topic: Hello from Kent
Replies: 10
Views: 1114

Re: Hello from Kent

Thanks all. I like a bit of problem solving. It would be good to breathe some life back into my Elk, although I probably last tried about ten years ago. I think my dead Beebs have problems with power supply and broken circuit tracks. I shall dig them out and start tinkering. Wish I had an oscillosco...
by ComanderJameson
Tue Oct 08, 2013 1:58 pm
Forum: introduce yourself
Topic: Hello from Kent
Replies: 10
Views: 1114

Hello from Kent

A warm hello to everyone. I blame my uncle for being on here. Mostly because he introduced me to his ZX81 circa 1982... I badgered my parents for my own ZX81, which I got eventually. Only to see the BBC Micro on TV shortly after. Colour, graphics, AND sound. My parents got me an Electron. Ah well. S...