Search found 109 matches

by ctr
Wed Feb 21, 2018 2:07 am
Forum: emulators
Topic: Double-clicking .SSD overrides VDU 14 ?!
Replies: 13
Views: 335

Re: Double-clicking .SSD overrides VDU 14 ?!

So the only way to stop the emulator pressing Shift (after a double-click on the .SSD) and scrolling the screen is to change the program (or the !BOOT) to ask for user-input first? I just tried b-em and it also cancels the shift if you don't press a key for a couple of seconds. So you could use INK...
by ctr
Wed Feb 21, 2018 12:21 am
Forum: emulators
Topic: Double-clicking .SSD overrides VDU 14 ?!
Replies: 13
Views: 335

Re: Double-clicking .SSD overrides VDU 14 ?!

The emulator is probably simulating a shift key-press to make the shift+break work. This also allows the text to scroll. The emulator may well cancel the fake key-press when you press a key.
by ctr
Mon Feb 19, 2018 7:48 pm
Forum: software: other
Topic: Hacking the school Econet
Replies: 15
Views: 457

Re: Hacking the school Econet

I wrote some code to intercept the command line interpreter vector and told the teacher I needed him to configure something for me, knowing he would use my computer. When he logged in my code recognised the command, displayed the usual prompt, squirelled away the password, unhooked the vector and di...
by ctr
Sat Feb 17, 2018 2:48 am
Forum: stardot.org.uk
Topic: Stardot logo fixed and now spud and banana free!
Replies: 57
Views: 966

Re: Stardot logo disappeared!

richardtoohey wrote:I was so curious about this spud that I pressed Ctrl+R and now I have it as well. :D

(I posted the proper logo on page 1 in case it got missed?)

I am so confused right now. The wine doesn't help. This is what I see:
by ctr
Mon Feb 12, 2018 5:16 pm
Forum: development tools
Topic: BeebAsm
Replies: 30
Views: 2048

Re: BeebAsm

I must admit I got a bit nervous on seeing your long post and expected you'd found a lot of bugs, so I'm glad it all seemed OK. :-) Yeah, by the time I'd finished testing I realised I had quite a long post that really didn't say very much. But thank you for making the couple of changes. We could po...
by ctr
Sun Feb 11, 2018 11:59 pm
Forum: development tools
Topic: BeebAsm
Replies: 30
Views: 2048

Re: BeebAsm

I tested the changes in your proposed-updates branch. I tested that each feature works in a couple of simple cases and that it handled any error or corner cases I could think of. I've looked at a bit of the code but I haven't reviewed any of it in detail. PUTBASIC automatic line-numbering is missing...
by ctr
Sun Feb 11, 2018 4:13 pm
Forum: development tools
Topic: BeebAsm
Replies: 30
Views: 2048

Re: BeebAsm

I've had a quick play with this. It seems to work pretty well to me and the implementation is nice and simple. I did think the syntax was a little ugly, but it really isn't that bad and it's already growing on me. Thanks for having a look. An alternative syntax could be "?=", which would ...
by ctr
Fri Feb 09, 2018 11:11 am
Forum: development tools
Topic: BeebAsm
Replies: 30
Views: 2048

Re: BeebAsm

I have a BeebAsm related question. Is there any way to test if a variable is already defined in an IF expression? I would like to use this to provide a default value, if one is not already set. Dave The short answer is not in the current version. There is a patch to add IFDEF but this causes unavoi...
by ctr
Tue Feb 06, 2018 5:14 pm
Forum: development tools
Topic: BeebAsm
Replies: 30
Views: 2048

Re: BeebAsm

I've had a bash at summarising that RS thread. The requirements seem to be: 1. Allow conditional compilation; 2. with options that can be overridden on the command-line; 3. or overridden in an outer asm file that includes the main asm file. The difficulties were: 1. Attempting to use a symbol that m...
by ctr
Thu Jan 25, 2018 7:59 pm
Forum: adventures
Topic: Level 9 posters
Replies: 6
Views: 389

Re: Level 9 posters

by ctr
Thu Jan 04, 2018 1:01 pm
Forum: archive issues
Topic: Flip! - Icon
Replies: 18
Views: 777

Re: Flip! - Icon

CMcDougall wrote:just tried both on emulator (BeebEm414 1770 2.26DFS &bEm22)

I hadn't noticed this detail previously. I'm using beebem with the 8271 and DFS 1.20.
by ctr
Tue Jan 02, 2018 5:27 pm
Forum: archive issues
Topic: Flip! - Icon
Replies: 18
Views: 777

Re: Flip! - Icon

This is the conversion I did bitd :^o it says 2011 CTR in the !Boot :-s Caught red-handed! I did the disk conversion back in the 80s with multiple games per disk. In 2004 I transferred all the disks to ssd files and in 2011 I rearranged them with one ssd per game, but whatever butchery I did to the...
by ctr
Sun Dec 31, 2017 9:51 pm
Forum: archive issues
Topic: Flip! - Icon
Replies: 18
Views: 777

Re: Flip! - Icon

This is the conversion I did bitd. I was able to complete a game using beebem (and 46 tries :oops:).
by ctr
Sun Dec 31, 2017 12:27 pm
Forum: hardware
Topic: Random pixels on BBC Model B
Replies: 60
Views: 1338

Re: Random pixels on BBC Model B

JannievanZyl wrote:Is the 1K RAM used for teletext within the same memory space as the 20KB used for high res graphics?


Yes, all modes use RAM immediately below &8000. So teletext is &7C00-&8000 (with a few spare bytes) and 20KB modes are &3000-&8000.
by ctr
Sun Dec 31, 2017 12:09 pm
Forum: hardware
Topic: Random pixels on BBC Model B
Replies: 60
Views: 1338

Re: Random pixels on BBC Model B

It starts in Mode 7, which is the teletext mode with one byte per character. Pound signs have character code 0x60 or 01100000 in binary.
by ctr
Wed Dec 06, 2017 1:56 am
Forum: emulators
Topic: MAME: Video handling
Replies: 8
Views: 849

Re: MAME: Video handling

This graphics corruption on the master could be caused by the code using OS lookup tables to render pixels. The lookup tables moved between the beeb OS and master OS so code that relied on them broke on the master. In other words, it wouldn't work on a real master. The successful text rendering supp...
by ctr
Tue Sep 26, 2017 8:04 pm
Forum: programming
Topic: Using memory below &0E00 from BASIC
Replies: 34
Views: 1771

Re: Using memory below &0E00 from BASIC

So, for some reason BBC BASIC makes a distinction between 'immediate commands' like LIST, SAVE, etc, and the rest. You can't execute them in a program (they yield "Syntax error"), unlike most other BASICs. I'm not sure where it is but there's obviously an explicit check for this somewhere...
by ctr
Mon Sep 04, 2017 7:52 pm
Forum: emulators
Topic: Latest version of BeebEm
Replies: 28
Views: 2915

Re: Latest version of BeebEm

I've seen the Revs bug elsewhere and I've been meaning to look at it for a while, so I've pushed a fix . Sadly, this doesn't help The Shapes Game. That bug looks like a timing problem. The top half of the main sprite is sometimes fine, sometimes flickers and sometimes disappears, depending where on ...
by ctr
Mon Aug 28, 2017 3:40 pm
Forum: development tools
Topic: beebasm putbasic problem
Replies: 9
Views: 898

Re: beebasm putbasic problem

sydney wrote:I'm sure I'd read line numbers were optional.

That rang a bell so I had another look. Github has a bunch of proposed updates including automatic line numbering. Stardot has a thread about it.
by ctr
Mon Aug 28, 2017 2:29 pm
Forum: development tools
Topic: beebasm putbasic problem
Replies: 9
Views: 898

Re: beebasm putbasic problem

You can't omit the line numbers in your basic code. This is a nuisance.
by ctr
Wed Aug 23, 2017 11:05 pm
Forum: programming
Topic: How do you save a screen
Replies: 448
Views: 20675

Re: How do you save a screen

png might be a better choice. The last picture, "Toxic Wastedump.jpg", is 215KB. Converted to indexed png it is 10KB, and guaranteed lossless.
by ctr
Fri Aug 18, 2017 10:01 pm
Forum: projects
Topic: Going great guns on a Prince of Persia port...
Replies: 199
Views: 14098

Re: Starting a Prince of Persia port...

I'm not sure which assembler was originally used but the syntax is slightly different and it has a couple of more advanced features than BeebAsm, including the ability to identify local labels and variables for reuse. In beebasm you can use braces {} to create blocks. Labels and variables are local...
by ctr
Mon Aug 07, 2017 5:43 pm
Forum: software: games - high scores
Topic: High Score Challenge S7- Champ - Rocket Raid
Replies: 63
Views: 2256

Re: High Score Challenge S7- Champ - Rocket Raid

These are exactly the symptoms that I've been facing and it's extremely frustrating because it should be a bit smoother. I'm not sure if it's an emulator issue or if it happens in hardware too. I played this on real hardware last time it was part of the challenge and was able to get past the maze p...
by ctr
Mon Aug 07, 2017 5:20 pm
Forum: software: games - high scores
Topic: High Score Challenge S7- Champ - Rocket Raid
Replies: 63
Views: 2256

Re: High Score Challenge S7- Champ - Rocket Raid

After more than thirty years I finally completed a raid! I am absurdly pleased. Then I had no spare lives and died on level 2 (duh!) so I only scored 21,220. There seem to be no points for finishing. http://stardot.org.uk/forums/download/file.php?mode=view&id=31289 My best score of 25,030 was ac...
by ctr
Tue Aug 01, 2017 5:43 pm
Forum: emulators
Topic: Music 5000 in B-Em
Replies: 205
Views: 9595

Re: Music 5000 in B-Em

As a complete new person to this I've got a couple of funnies that would be good to sort out if anyone can help? From the user guide it says key F0 to get back to the main menu - Ah! no F0 function key here - is there a way back? And I wanted to save my O&L masterpiece! - but getting a READ ONL...
by ctr
Tue Aug 01, 2017 3:46 pm
Forum: emulators
Topic: Music 5000 in B-Em
Replies: 205
Views: 9595

Re: Music 5000 in B-Em

a large source of AMPLE music with accompanying MP3 files (recorded directly from the Music 5000 hardware) at http://amplinex.tumblr.com/. This is excellent. I stumbled across it a couple of months ago while looking for some music to test beebem. I did notice one minor hiccup: disk 22 seems to be a...
by ctr
Sat Jul 29, 2017 6:39 pm
Forum: hardware
Topic: AMX mouse
Replies: 4
Views: 400

Re: AMX mouse

Just type *ART to start a drawing program. Click the mouse button to make the "Bad name" error go away.
by ctr
Mon Jul 24, 2017 9:39 pm
Forum: hardware
Topic: *mzap and *define
Replies: 12
Views: 987

Re: *mzap and *define

I don't know which rom you're thinking of, but here's one I made earlier. The command is *DESIGN and it always starts at character 224. It uses the arrow keys, return to draw a pixel and del to delete. shift+arrow key moves the cursor to the far edge. ctrl+arrow key moves the image around. f0 and f1...
by ctr
Thu Jul 20, 2017 3:37 pm
Forum: software: other
Topic: osbyte call ? and which adress
Replies: 4
Views: 538

Re: osbyte call ? and which adress

I should have looked at the beeb wiki in the first place:

OSBYTE 129 with X=0 and Y=255 reads the OS version.

The original code is saying if this isn't an Electron then partially reset the NETV vector.

OSBYTE 163 checks for various extensions.
by ctr
Thu Jul 20, 2017 12:07 pm
Forum: software: other
Topic: osbyte call ? and which adress
Replies: 4
Views: 538

Re: osbyte call ? and which adress

&FFB7 holds the address of the default vector table. As seen here . !&FFB7 is the address of the default vector table (&D940 on OS 1.20). ?(&24+!&FFB7) is the low byte of the default NETV vector. ?&224 is the low byte of the NETV vector. So you are replacing the low byte of t...