Search found 2212 matches

by jms2
Tue May 14, 2019 6:46 pm
Forum: archive requests
Topic: Electron Le Box by PACE
Replies: 5
Views: 199

Re: Electron Le Box by PACE

I think the Amcom DFS was a version also available for the BBC. I don’t know if it’s online, but it probably is. I don’t know anything about the hardware but it must have been expensive because the price is not even mentioned! It also did not need a Plus 1, so there would have been some additional a...
by jms2
Sat May 11, 2019 10:02 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 10
Views: 490

Re: Looking for inspiration - debugging E2P

Made a few discoveries today: 1. There actually is a *GO command. This is in the B2P manual but I think not the E2P manual. 2. Typing CALL &F800 drops into a command line. Again I think this is only mentioned in the B2P manual. 3. If I change my test program to exit with JMP &F800, it works. So exac...
by jms2
Sat May 11, 2019 8:56 am
Forum: software: classic games
Topic: BBC B Elite versions
Replies: 12
Views: 496

Re: BBC B Elite versions

No idea - never heard of it! You might have found an interesting lost relic there. I assume its not an official release disc?
by jms2
Fri May 10, 2019 6:38 pm
Forum: archive requests
Topic: Genie/Genie Junior by PMS
Replies: 31
Views: 781

Re: Genie/Genie Junior by PMS

Ah, mode 1 - the memory requirement wouldn't be an issue with the second processor. I hadn't thought of that.
by jms2
Fri May 10, 2019 11:43 am
Forum: archive requests
Topic: Genie/Genie Junior by PMS
Replies: 31
Views: 781

Re: Genie/Genie Junior by PMS

That would be great - thanks!

I think I found a BBC version of Hi Wordwise Plus somewhere on the web, but as the ad says the Elk version is definitely different.
by jms2
Thu May 09, 2019 7:25 pm
Forum: archive requests
Topic: Genie/Genie Junior by PMS
Replies: 31
Views: 781

Re: Genie/Genie Junior by PMS

I think the Beeb version must be different, because it relies heavily on Mode 7, which the Elk doesn't have. Although it is possible that if you run the BBC version on the Elk it just defaults to Mode 6... I'm sure I have seen a PMS advert in Electron User advertising an Electron-specific version of...
by jms2
Thu May 09, 2019 3:28 pm
Forum: archive requests
Topic: Genie/Genie Junior by PMS
Replies: 31
Views: 781

Re: Genie/Genie Junior by PMS

I wrote almost all of the PMS code (with the exception of the B2P second processor, and the original RAM Disk). Hello Derek! I assume when you say "B2P" you are also including the E2P as well? I think the software for both of those was written by John Wike of JAFA systems, but I'd be interested to ...
by jms2
Wed May 08, 2019 8:22 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 10
Views: 490

Re: Looking for inspiration - debugging E2P

Here's the rom image. As far as I can tell, it is simply E2P v2.4 in a sideways rom "wrapper". When the command *E2PON is issued, it relocates the code to &2500 and executes it as if it came from disc. E2p.rom I have created a very slightly hacked version of v2.4 which I'm calling v.2.5. The only ch...
by jms2
Wed May 08, 2019 10:46 am
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 10
Views: 490

Re: Looking for inspiration - debugging E2P

I don't know if this helps at all, but this is my disassembly of the official release version of the E2P OS, version 2.4. E2P v2-4 disassembly.docx It's not source code, just disassembly. I can't remember what disassembler I actually used. The comments are what I have been able to understand myself ...
by jms2
Wed May 08, 2019 10:31 am
Forum: general
Topic: Acorn Electron press launch event: a shambles?
Replies: 6
Views: 368

Re: Acorn Electron press launch event: a shambles?

I remember reading the Electron User account of the launch. Despite their attempts to big it up, I thought it sounded a bit rubbish even though I was only 11 or 12 at the time! :lol:

It's nice to have that opinion confirmed by a more credible source.
by jms2
Sun May 05, 2019 6:04 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 10
Views: 490

Re: Looking for inspiration - debugging E2P

That's genius - I had a feeling that this was very much in your area of expertise Mr. Harston, but I didn't expect you to nail the problem quite so quickly! =D> If I understand correctly, you are saying that this version of the E2P OS has actually never worked properly? I wonder if this problem coul...
by jms2
Sat May 04, 2019 9:55 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 10
Views: 490

Re: Looking for inspiration - debugging E2P

*RUN did not help. I also tried relocating the code but this also made no difference. I did note something else interesting though. The code does execute and print the A, but as you say the RTS is returning to somewhere strange. Oddly though, whatever garbage this generates is persistent even after ...
by jms2
Sat May 04, 2019 9:08 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 10
Views: 490

Re: Looking for inspiration - debugging E2P

Good call Martin, I can't remember whether I tried that. I'll give it a go.
by jms2
Sat May 04, 2019 12:14 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 10
Views: 490

Looking for inspiration - debugging E2P

My extremely-long-term project to recreate the JAFA/PMS Electron Second Processor hardware has finally reached the point of a real PCB: E2P board.JPG I have found that it works (note that I have installed the E2P rom, which means I don't need to load the OS from disc any more): Running.JPG This is w...
by jms2
Sun Apr 28, 2019 7:25 am
Forum: projects
Topic: BBC Micro and Acorn Electron demo effects
Replies: 58
Views: 1947

Re: Acorn Electron demo effects

Every Electron emulator I've tested yields a slightly different result and requires some tweaking. To tweak the timing press CURSOR UP or CURSOR DOWN. Watch the topleft of the screen where a number appears according to the current setting. Press ESCAPE to hide this number again. On my Electron I ge...
by jms2
Thu Apr 25, 2019 6:24 pm
Forum: software: classic games
Topic: Imogen - new review
Replies: 7
Views: 446

Re: Imogen - new review

Thanks for another excellent review! I didn't know there was ever an Electron version.
by jms2
Tue Apr 23, 2019 8:01 pm
Forum: software: classic games
Topic: Beeb games that work on the Elk
Replies: 2
Views: 230

Re: Beeb games that work on the Elk

Yes, quite a lot of BBC games do work. This was the subject of a few articles in Electron User in the early days as I recall, probably because Acorn were understandably vague in their advertising regarding the level of compatibility between the two machines, such that many Electron users started fro...
by jms2
Tue Apr 23, 2019 6:44 pm
Forum: software: other
Topic: Accessing sideways ram from an event handler
Replies: 7
Views: 216

Re: Accessing sideways ram from an event handler

It isn't clear to me what machine you are targetting either, is it the Elk then? Whoops, yes I should have said that. I don't know about the elk, nor if it is legal on the beeb, but in an interrupt, not calling the is or unknown code, I don't change &F4, but use it to restore romsel. I suspect that...
by jms2
Tue Apr 23, 2019 2:10 pm
Forum: software: other
Topic: Accessing sideways ram from an event handler
Replies: 7
Views: 216

Re: Accessing sideways ram from an event handler

Yes, I'm pretty sure... although my code doesn't use the JSR:

\A=rom number
PHA
LDA#12
STA &F4
STA &FE05

PLA
STA &F4
STA &FE05

Am I OK using the stack in this way?
by jms2
Tue Apr 23, 2019 12:33 pm
Forum: software: other
Topic: Accessing sideways ram from an event handler
Replies: 7
Views: 216

Re: Accessing sideways ram from an event handler

Good call. Yes I did, from memory I did: LDA romnumber STA &F4 STA &FE05 I also used the Electron-specific "double select" method where you select a high-numbered rom first and then the required rom. Another thing that I realized you need to do is read the current rom number from &F4 rather than fro...
by jms2
Tue Apr 23, 2019 11:45 am
Forum: software: other
Topic: Accessing sideways ram from an event handler
Replies: 7
Views: 216

Accessing sideways ram from an event handler

I have written a short piece of event-driven code which I'm using to monitor the contents of sideways ram for hardware testing purposes. It works, but is not 100% reliable - ie it crashes about 4 times out of 5. I suspect that some aspect of the way I am handling events is not quite right, but I can...
by jms2
Sun Apr 21, 2019 8:20 pm
Forum: general
Topic: Design a logo for ABug!
Replies: 25
Views: 2481

Re: Design a logo for ABug!

I have done some experimenting and have attached three files here: 1) The original logo as a PNG. 2) The logo with a transparent background instead of black. As I thought, this doesn't look great. 3) As above, but with a black outline around the edges. This is better but still not ideal. 4) A rearra...
by jms2
Sun Apr 21, 2019 6:23 am
Forum: general
Topic: Design a logo for ABug!
Replies: 25
Views: 2481

Re: Design a logo for ABug!

Technically its no problem. You can even have a transparent background. However I would be concerned that the lettering might not show up so well. I might need to add a black outline.
by jms2
Sat Apr 20, 2019 10:09 pm
Forum: general
Topic: Design a logo for ABug!
Replies: 25
Views: 2481

Re: Design a logo for ABug!

I'm on the case...

Still really chuffed that people like the logo. It wasn't even a serious suggestion, but I suppose that's part of its appeal.
by jms2
Fri Apr 12, 2019 4:23 pm
Forum: hardware
Topic: Save my Elk...
Replies: 25
Views: 670

Re: Save my Elk...

Yes, I think so. I would put the JMP at the end of page &FB so that your NOPs don't get messed up by the hardware addresses present in the following pages. It's worth hanging around a bit to get confirmation from someone else first though! Regarding interrupts, there are three kinds - NMI (non maska...
by jms2
Fri Apr 12, 2019 2:48 pm
Forum: hardware
Topic: Save my Elk...
Replies: 25
Views: 670

Re: Save my Elk...

I have not made a NOP-generating ROM before, but I want to suggest an answer to your question (mainly to see if my own understanding is right!): On the Electron OS and BASIC are in one 32k ROM, so that would span the address range from &8000 to &FFFF [that bit I am confident of!] On reset, the 6502 ...
by jms2
Tue Apr 09, 2019 11:49 am
Forum: hardware
Topic: Mysterious Electron Plus4 expansion
Replies: 2
Views: 165

Re: Mysterious Electron Plus4 expansion

I share your sense of intrigue in this! I've got no idea what it is, but the date codes (on the ICs as well as on the rom label) suggest it was made in 1987. One thought is that it was not sold under the name "Plus 4" but as something else. It's professionally made, but not PRES, Slogger or Watford ...
by jms2
Mon Apr 08, 2019 6:48 pm
Forum: software: classic games
Topic: Getting started with Exile...
Replies: 21
Views: 692

Re: Getting started with Exile...

Well done! Yes, it is hard. Not only that, but unlike any other game I've played Exile really has the feeling of being a bitter struggle. That sounds bad, but I thought it was a really good and lifelike feature. You really feel sorry for Finn as he screams in pain from being burned/blown up/shot/bit...
by jms2
Mon Apr 08, 2019 6:44 pm
Forum: introduce yourself
Topic: Acorn Newbie
Replies: 23
Views: 395

Re: Acorn Newbie

I have just cleaned the ULA contacts on my Issue 4 so I'm in a good position to explain how to do it. The ULA is the biggest chip, the one with the metal "X" over it. This X shaped thing is a clip which holds the ULA into a ZIF socket. To release the clip, you need to pick any corner and use a small...
by jms2
Sun Apr 07, 2019 1:09 pm
Forum: programming
Topic: Turbo Elk
Replies: 10
Views: 411

Re: Turbo Elk

Also... as you're clearly interested in this kind of thing, have a look at the attached. This is the Electron Advanced User Guide, which I have been updating a bit in recent years. All the new information has come either from original sources or from the clever people on this forum (I just type it i...