Search found 2221 matches

by jms2
Thu Jun 20, 2019 7:16 pm
Forum: hardware
Topic: What's In My Beeb?
Replies: 33
Views: 603

Re: What's In My Beeb?

You can (and probably should) remove all of the roms except for the OS, BASIC, and SmartSPI.

The small board on the left of the motherboard contains the floppy disc controller. I guess you could remove that, but I doubt it will help.
by jms2
Mon Jun 17, 2019 6:23 pm
Forum: hardware
Topic: Who on here has the earliest Acorn Electron?
Replies: 7
Views: 222

Re: Who on here has the earliest Acorn Electron?

I had an early Electron as a kid, but I don't think it was for Christmas. It would say it was spring 1984. Sadly I no longer have this machine. My parents bought it on the recommendation of the head teacher at my primary school, who had somehow found out about the Electron and advised them that it w...
by jms2
Mon Jun 10, 2019 11:20 am
Forum: programming
Topic: VDU ?
Replies: 21
Views: 533

Re: VDU ?

I think what Lardo was getting at was that "8202" is one byte shorter than "10,32" and that this was possibly why that form, rather than the latter, was put into the User Guide. The 10,32 form is easier to understand if you have access to the Advanced User Guide to understand what the individual par...
by jms2
Sun Jun 09, 2019 6:47 am
Forum: programming
Topic: VDU ?
Replies: 21
Views: 533

Re: VDU ?

I assume the reason why people started using the "8202" form of the command was because it is slightly easier to remember and to type compared to the intelligible version of the command. I'm as guilty as anyone else for using it, so I guess it has some value. All the same it seems like an odd thing ...
by jms2
Tue Jun 04, 2019 5:55 am
Forum: community projects
Topic: New Advanced User Guide (Remastered)
Replies: 15
Views: 400

Re: New Advanced User Guide (Remastered)

I was aware that the NAUG wasn't held in very high regard, but I assumed that this was because of its rather confusing layout rather than actual errors. The AUG on the other hand, whilst it has a lot of omissions, I hadn't heard of any specific errors in it. I'm wondering how easy it would be to get...
by jms2
Mon Jun 03, 2019 7:17 pm
Forum: community projects
Topic: New Advanced User Guide (Remastered)
Replies: 15
Views: 400

Re: New Advanced User Guide (Remastered)

...hang on, I've just noticed this isn't the same thread as the one I spotted earlier. You've done both books... how is that possible?!

Just incredible!
by jms2
Mon Jun 03, 2019 7:16 pm
Forum: community projects
Topic: New Advanced User Guide (Remastered)
Replies: 15
Views: 400

Re: New Advanced User Guide (Remastered)

You're the master at this - I wasn't even aware that there were any errors in the AUG! =D>

The question now is - I was planning on bidding for a paper version, but now I'm not so sure that I want one...
by jms2
Fri May 31, 2019 11:50 am
Forum: other vintage computer hardware, software and games
Topic: C64C Reasonable price...
Replies: 9
Views: 352

Re: C64C Reasonable price...

Recently I sold a boxed, working breadbin C64 on Ebay for about £75, including C2N and some games. I started the auction at £25 so I reckon the final selling price represents the market value (on Ebay at least). I don't know whether the C64C is worth more or less, but this might help as a starting p...
by jms2
Wed May 29, 2019 4:14 pm
Forum: hardware
Topic: Looking for inspiration - debugging E2P
Replies: 11
Views: 593

Re: Looking for inspiration - debugging E2P

I have been making quite a lot of progress with this, using Jonathan's excellent commented source for the Acorn Tube client code on MDFS. My strategy is to find out how that works, and compare it with the equivalent E2P code to see where the similarities and differences lie. I have found quite a lot...
by jms2
Tue May 14, 2019 6:46 pm
Forum: archive requests
Topic: Electron Le Box by PACE
Replies: 5
Views: 241

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: 11
Views: 593

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: 26
Views: 970

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: 42
Views: 1023

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: 42
Views: 1023

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: 42
Views: 1023

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: 42
Views: 1023

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: 11
Views: 593

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: 11
Views: 593

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: 404

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: 11
Views: 593

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: 11
Views: 593

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: 11
Views: 593

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: 11
Views: 593

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: 69
Views: 2804

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: 487

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: 253

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: 244

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: 244

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: 244

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: 244

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...