Search found 827 matches

by Coeus
Sat Jul 21, 2018 2:06 pm
Forum: hardware
Topic: So, how *do* I get hold of an MMFS ROM?
Replies: 14
Views: 285

Re: So, how *do* I get hold of an MMFS ROM?

Thanks guys! I am having vague flashbacks to 30 years ago when, IIRC, my Beeb had page at &1900, now that I come to think of it. So I'm coming round to T/MMFS! More compatible if I ever want to move it to a machine without SWRAM as well. (And I didn't suggest one of each because I don't want to put...
by Coeus
Fri Jul 20, 2018 10:39 pm
Forum: off-topic
Topic: Using BBC BASIC to teach programming concepts in 2017
Replies: 87
Views: 2359

Re: Using BBC BASIC to teach programming concepts in 2017

Anyway the point of all my ramblings is that I don’t think their thinking was a bug but just thinking outside the box. Interesting this "everything happens all the time" model that isn't right for an imperative programming language is very similar to how asynchronous logic work and you have to add ...
by Coeus
Fri Jul 20, 2018 10:25 pm
Forum: off-topic
Topic: Football
Replies: 9
Views: 242

Re: Football

if it was girls with shorts on.... I may watch it =P~ I think the tennis is good for that kind of watching. Actually, ladies tennis is more interesting to watch as a game and not just for watching the players. Men's tennis when I last saw it was dominated by the service with a high proportion not r...
by Coeus
Fri Jul 20, 2018 10:15 pm
Forum: software & utilities for the pc, mac or unix
Topic: Matrix Brandy BASIC V for Linux with SDL
Replies: 6
Views: 150

Re: Matrix Brandy BASIC V for Linux with SDL

I don't have access to RiscOS so I can't jump in and look but if you want a second pair of eyes on this and can attach that test file as saved from RiscOS I will see if I can take a look.
by Coeus
Fri Jul 20, 2018 10:03 pm
Forum: hardware
Topic: So, how *do* I get hold of an MMFS ROM?
Replies: 14
Views: 285

Re: So, how *do* I get hold of an MMFS ROM?

I cannot comment on the virtues of the different ROMS for card readers, though I use MMFS myself and have made a very small contribution to it. I do have an EPROM eraser, programmer and some EPROMs squirrelled away and would be happy to program one for you. I'll check how much I paid for the EPROMs ...
by Coeus
Fri Jul 20, 2018 2:46 pm
Forum: general
Topic: "Outline specification for the BBC MICROCOMPUTER system"
Replies: 203
Views: 16256

Re: "Outline specification for the BBC MICROCOMPUTER system"

Of course, as laws changed and original manufacturers wised up, so the problem of unlicensed clone machines disappeared as far as most manufacturers were concerned. As far as complete machines are concerned I think things have changed somewhat since then, technically, too. Back then people wrote so...
by Coeus
Sun Jul 15, 2018 7:33 pm
Forum: other vintage computer hardware, software and games
Topic: Datel Modem 1979 to 1982, anyone used it?
Replies: 15
Views: 419

Re: Datel Modem 1979 to 1982, anyone used it?

I think I have just spotted one of these in use in Episode 10 "At The End of the Line" of "Making the Most of the Micro" at about 11:45. See this still:
Screenshot from 2018-07-15 20-14-36.png
by Coeus
Sun Jul 15, 2018 2:03 pm
Forum: software: other
Topic: Today I hacked ...
Replies: 91
Views: 9484

Re: Today I hacked ...

by 8271 you don't need track 0 , sec 0 sec1 and sec2. look at my disc protect systeem :). if the 8271 do not find after index hole track 0,sec0,1 it steps 255 times all over de disc to find it :) so track 0 sec1,sec2 can be at track 9 the only thing you have to do is make track 9 the ids for track ...
by Coeus
Sun Jul 15, 2018 8:36 am
Forum: software: other
Topic: Today I hacked ...
Replies: 91
Views: 9484

Re: Today I hacked ...

yeah, but how ? When reading, I would not expect the disc controller to use the index hole at all. It will simply start reading data until it finds the ID for the specified sector and will then generate the interrupt to start transferring that sector. So, with all the sectors having the same ID whi...
by Coeus
Sat Jul 14, 2018 8:13 pm
Forum: programming
Topic: Files created by OPENOUT
Replies: 4
Views: 313

Re: Files created by OPENOUT

Are there any technical details of the file format used by files created using the OPENOUT command function? Any files created by any method have no format, they are pure binary. Any internal format of the binary data is entirely and completely down to the programmer chosing what to so with it. It ...
by Coeus
Wed Jul 11, 2018 4:36 pm
Forum: off-topic
Topic: Football
Replies: 9
Views: 242

Re: Football

I probably will be watching the match but I am not proposing to watch the hype before hand or the endless analysis afterwards. The pundits have quite enough time in between the two halves to chinwag. Until kickoff I am listening to music and staying away from media that may choose to speculate about...
by Coeus
Tue Jul 10, 2018 6:31 pm
Forum: software: other
Topic: CP/M Hard Disc BIOS
Replies: 1
Views: 93

CP/M Hard Disc BIOS

Questions, probably for JGH: Disc http://mdfs.net/Mirror/Image/AcornCPM/JGHCPM1.zip is a CP/M bootable disc with a hard disc BIOS. 1. Does this make any assumptions about the disc interface, i.e. SCSI or IDE. 2. Does it need reserved tracks on the disc or does it turn an ADFS file into a virtual har...
by Coeus
Tue Jul 10, 2018 6:26 pm
Forum: software: other
Topic: Acorn CP/M disc format
Replies: 1
Views: 105

Acorn CP/M disc format

I notice Acorn CP/M format discs have a fake DFS catalogue at the start on side 0. As far as I can work out this contains a single file that occupies the whole disk (side) and thus ensures the user cannot save files to the disc from DFS and overwrite CP/M files. Shouldn't there be a similar fake cat...
by Coeus
Tue Jul 10, 2018 6:20 pm
Forum: software: other
Topic: CP/M text Editor Required
Replies: 9
Views: 250

Re: CP/M text Editor Required

The other thing I forgot to suggest is that all the other obscure commands can be programmed into function keys with *KEY and you could make a keystrip with a suitable legend. To set up some things ready for running VDE for the first time in any one session you can always place the commands in a SUB...
by Coeus
Tue Jul 10, 2018 4:16 pm
Forum: software: other
Topic: CP/M text Editor Required
Replies: 9
Views: 250

Re: CP/M text Editor Required

Further to my last post, here is a disc (in Acorn CP/M format, so ready to go on Z80 2nd proc) with VDE configured for the BBC micro, i.e. I have been through the installation program and set up the terminal control sequences to be the BBC VDU sequences. The other half of the picture, i.e. making th...
by Coeus
Tue Jul 10, 2018 3:42 pm
Forum: other vintage computer hardware, software and games
Topic: Datel Modem 1979 to 1982, anyone used it?
Replies: 15
Views: 419

Re: Datel Modem 1979 to 1982, anyone used it?

1024MAK wrote:
Tue Jul 10, 2018 12:24 pm
MODEMs designed only for exchange line use normally need something to simulate the exchange...
For an auto dialing modem this simulation would need to be more complete but without autodial I wonder if you could get away with connecting a pair of these back to back and just provide the DC 50V.
by Coeus
Tue Jul 10, 2018 12:45 pm
Forum: software: other
Topic: CP/M text Editor Required
Replies: 9
Views: 250

Re: CP/M text Editor Required

...ED for me is completely unusable... I remember thinking that, back in the day. Then, I didn't understand why "they" (Digital Research) thought a line editor was a good idea but at that age I didn't have a sense of how fast progress in computing had been and that when CP/M was designed having a V...
by Coeus
Tue Jul 10, 2018 9:51 am
Forum: programming
Topic: BASIC FOR loops
Replies: 15
Views: 298

Re: BASIC FOR loops

I disagree. Perhaps it is a little confusing for the beginner but it is the equivalent to "break [n];" in C. A very useful feature for more advanced program flow control. In the the case of the Mandelbrot program that started this, it is only a single level of break in equivalent C. Here's the part...
by Coeus
Tue Jul 10, 2018 9:06 am
Forum: programming
Topic: BASIC FOR loops
Replies: 15
Views: 298

Re: BASIC FOR loops

Soruk wrote:
Mon Jul 09, 2018 10:18 pm
Hi,

Your patch works a treat for that Mandelbrot thing over in the other thread.

May I include it in my fork of Brandy?
Yes, that's fine.
by Coeus
Mon Jul 09, 2018 9:24 pm
Forum: programming
Topic: BASIC FOR loops
Replies: 15
Views: 298

Re: BASIC FOR loops

Ok, so to follow up my post it seems there is an ANSI standard for BASIC, I just wasn't aware of it. That doesn't make any material difference, though, as I was specifically asking about Acorn BASICs.
by Coeus
Mon Jul 09, 2018 9:11 pm
Forum: programming
Topic: BASIC FOR loops
Replies: 15
Views: 298

Re: BASIC FOR loops

The phrase "Implementation defined behaviour" sounds like what you'd expect to in a language standard but I was not aware of any effort to produce a proper language standard for BASIC. As a practical matter, across BASIC implementations in general this does seem to vary. For example on CP/M Microsof...
by Coeus
Mon Jul 09, 2018 7:54 pm
Forum: emulators
Topic: emulator cycle vs walclock vs TIME accuracy
Replies: 8
Views: 487

Re: emulator cycle vs walclock vs TIME accuracy

I was trying to make sense of these figures from Brandy BASIC: Screenshot from 2018-07-09 19-33-46.png The overall theme seems to be that Brandy on my PC is a bit over 36,000 X as fast as a BBC unless floating point is involved in which case having hardware floating point is making an even bigger di...
by Coeus
Mon Jul 09, 2018 7:31 pm
Forum: software: other
Topic: Border tracing Mandelbrot generator for the Beeb
Replies: 83
Views: 6307

Re: Border tracing Mandelbrot generator for the Beeb

I've got a different mandelbrot that is using nested FOR loops working fine in Brandy. It would be interesting to see that to compare. Brandy can obviously do nested for loops but its setting an extra constraint compared to Acorn BASICs that the next needs to match the most recent FOR. I think the ...
by Coeus
Mon Jul 09, 2018 6:34 pm
Forum: emulators
Topic: Ceefax Engineering Test Page - BeebEm 4.13 & B-em
Replies: 67
Views: 10776

Re: Ceefax Engineering Test Page - BeebEm 4.13 & B-em

Just popping my head above the parapet here to say this thread has been a very useful resource in my attempt to make a reasonable emulation of Teletext work in Brandy BASIC V, along with a few Risc OS 5 extensions controlled via VDU23,18 as documented by BeebWiki. If anyone is interested I've put i...
by Coeus
Mon Jul 09, 2018 6:11 pm
Forum: programming
Topic: BASIC FOR loops
Replies: 15
Views: 298

Re: BASIC FOR loops

Ok, then in that case here is a patch to brandy basic that makes it behave like Acorn BASIC with these loops: --- brandy-1.21.2-orig/src/mainstate.c 2013-06-28 15:23:16.000000000 +0100 +++ brandy-1.21.2-patched/src/mainstate.c 2018-07-09 18:49:29.975604126 +0100 @@ -1301,6 +1301,20 @@ /* ** 'exec_ne...
by Coeus
Mon Jul 09, 2018 4:27 pm
Forum: programming
Topic: BASIC FOR loops
Replies: 15
Views: 298

BASIC FOR loops

I mentioned in another thread in which a Mandelbrot program in BASIC was included that brandy basic does not handle FOR loops where a NEXT statement occurs for anything other than the innermost FOR loop. I had a look in original BBC Micro User guide and it advises against "bady nested" FOR loops but...
by Coeus
Sun Jul 08, 2018 4:50 pm
Forum: other vintage computer hardware, software and games
Topic: Datel Modem 1979 to 1982, anyone used it?
Replies: 15
Views: 419

Re: Datel Modem 1979 to 1982, anyone used it?

I think I have seen one of those but never used one in person, though I do remember the days of 300, then 1200, then 2400 bps. There may be two reason why it was integrated into a phone: 1. It probably wasn't auto dialing so the phone would be needed to dial the connection. 2. The post office was st...
by Coeus
Sat Jul 07, 2018 8:58 pm
Forum: general
Topic: BBC releases computer history archive
Replies: 90
Views: 1967

Re: BBC releases computer history archive

First programme in the series "Making the Most of the Micro" has a very cool bit with Ian McNaught-Davies appearing to walk over a macro image of what looks like it may be a BBC micro, but not an issue 7 as far as I can see. I assume the effect is a colour separation overlay? Anyway, the featured ci...
by Coeus
Sat Jul 07, 2018 6:35 pm
Forum: general
Topic: BBC releases computer history archive
Replies: 90
Views: 1967

Re: BBC releases computer history archive

Does anyone recognise the chip shown in episode 9 of "The Computer Programme", "In Control" at around 18 minutes. The chip being held has Ferranti on it so a ULA, possibly? That would be consistent with Ian McNaught-Davis taking about customising the chip to a particular purpose as the last step in ...
by Coeus
Tue Jul 03, 2018 9:34 pm
Forum: general
Topic: "Outline specification for the BBC MICROCOMPUTER system"
Replies: 203
Views: 16256

Re: "Outline specification for the BBC MICROCOMPUTER system"

Edit: also it took about 5 years to really take off in the home market. In that time loads of other machine had been and gone. And the home market penetration was presumably because, once there were a number of clones, at least some of the clone manufacturers were then competing to see who could pr...