Econet (or standalone!) Jumbo Text Scroller

[JimR]

Merry Christmas everyone!

I've written a program which scrolls large text across the screen or — if you have Econet — multiple screens. I had a lot of fun writing it and maybe you'll find it interesting.

Here it is: https://github.com/jprayner/bbc-jumbo

If you find yourself at a loose end, I'd love to see you spin it up, take a short video and use it to share your own message to stardot whether you've a single, cherished Beeb or a full-fat Econet network.

Anyway, best wishes to my very favourite corner of the web.

Cheers,

Jim

[jms2]

That's very impressive, especially on a network. I can imagine it getting used in various "retro classroom" setups!

Sadly I don't have an econet myself, but it looks exceptionally smooth and elegant.

[JimR]

Thanks Jim! You can run it standalone (no Econet) by the way.

Interestingly, it's like butter on 3 out of 4 of my currently-working BBCs (including my model B). For some reason one of my Masters seems to glitch every few seconds. It's identical in every respect to one of the others (MOS version, other ROMs, what's plugged in). Would be interested to hear if anyone else sees that. I wonder if it's a hardware issue... (but a software guy would say that

BTW, I've found a couple of your posts useful in the past — nice to meet you!

[IanB]

I remember Acorn had something like this on their exhibition stands in the early years (certainly the first Acorn User show) using many systems attached to Microvitec monitors that wrapped around the top of their stand but in addition to text it had giant versions of the characters from the Snapper and Monsters games etc.

Anyone else remember that?

Maybe you could get something approximating that with user defined characters?
Or perhaps improve your code to support multi colour sprites. I think there may have been some animation as well using palette switching.

[FourthStone]

This is nicely done!

We had a program, type in I if I remember, for a large scroller in mode 7, don't think it worked on econet though.

[!FOZ!]

I LOVE this and can totally imagine it being a huge attraction BITD in my schools computer room - nice one!

BTW, if you are interested in scrollers in general I have been having a play with LED matrix scrollers over here.

[tricky]

Probably way more effort than it is worth, but can you adjust the alignment to match the monitor spacings?

[JimR]

Hi Tricky,

Yes, you can do this by tweaking this line of scroll.asm:

Code: Select all

    ; # 160 pixels / 2 pixels per scroll frame = 80 frames per page
    ; but add 10 more frames to allow for gap between physical screens
    ldy #90

10 frames == 20 pixels or 1/8th of the (mode 2) screen. Prolly a bit on the low side. Hmmm... maybe I should make this configurable from the start menu...

[markusher]

Would it be possible to read the message and parameters for the stations from a file? This way it can be set to auto !boot with no user intervention.
e.g. *I AM SCROLLER would login and boot the program and start the display.

[BeebMaster]

I really must try this (and Piconet which has been sitting in its opened box on top of Station 87 for weeks) and maybe I'll even do a video. It's going to take me a very long time to think of something more original than "Hello World".

[JimR]

Would it be possible to read the message and parameters for the stations from a file? This way it can be set to auto !boot with no user intervention.
e.g. *I AM SCROLLER would login and boot the program and start the display.

Of course! First create your user and home dir, then set your boot option to EXEC the script we're about to create...

Code: Select all

*I AM SYST
*NEWUSER SCROLLER
*CDIR $.SCROLLER
*I AM SCROLLER
*OPT 4,3

Then create a !BOOT file like this:

Code: Select all

*LOAD "Code"
*BASIC
LAUNCH=&2000:RUNMODE=&2700:MSGBUF=&2702
$MSGBUF="Don't panic...      "
?RUNMODE=1
CALL LAUNCH

...and copy Code (the machine code bit) from the release https://github.com/jprayner/bbc-jumbo/releases/

Alternatively, here's a zip with both files in it.

SCROLLER.zip

(1.96 KiB) Downloaded 7 times

[JimR]

I really must try this (and Piconet which has been sitting in its opened box on top of Station 87 for weeks) and maybe I'll even do a video. It's going to take me a very long time to think of something more original than "Hello World".

It would be great if you did do a video, BeebMaster! I built my Econet using the instructions on your site so then the circle would be complete...