Bitstik roms. What do they do?

discuss both original and modern hardware for the bbc micro/electron
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pstnotpd
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Bitstik roms. What do they do?

Post by pstnotpd » Sun Sep 05, 2010 4:14 pm

I managed to get my hands on a bitstik. It's actually marked ROBO BITSTIK 1 instead of the acorn one but it seems to work fine. I.e. all buttons and XYZ movement of the stick translates to adval values and I can play elite with it.

It doesn't come with any ROMS however so I downloaded those and loaded them up in my masters sideways RAM bank. I get the correct *HELP messages but haven't got a clue what they are supposed to do further.

A quick look in the the rom disassembly shows it only seems to implement some OSBYTE & OSWORD service calls. And somewhere in the ROM it seems to do a hard load from 0:$.PD. Anybody got an idea what these do?

A search on the internets gave suprisingly little information. I found someone mentioning the actual "graphics system" is in the rom. And the user guide seems to only cover the actual disk software.
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Samwise
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Re: Bitstik roms. What do they do?

Post by Samwise » Sun Sep 05, 2010 7:55 pm

Can't help right now, but I do have a complete Acorn Bitstik package with disc/ROM/instructions etc.

Sounds like you may have virtually everything I've got, though. I haven't really had time to do anything with it as I don't have easy access to a beeb, though I hope to look at it eventually. I'd certainly be interested in details of whatever you uncover ... esp. details on how it differs compared to a joystick.

I haven't even had chance to try it with Elite yet. You say that it works without the need for ROMs? Does it work just like a joystick but with the additional rotational axis used to adjust speed?

Sam.

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MartinB
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Re: Bitstik roms. What do they do?

Post by MartinB » Sun Sep 05, 2010 8:17 pm

Some very good info on Chris Whyehead's site here. The review article clearly explains the philosophy of the device.

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Samwise
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Re: Bitstik roms. What do they do?

Post by Samwise » Mon Sep 06, 2010 12:39 am

A brief snippet from the tech specs here.
- An 80 track disc containing system master software, utilities and a sample library of drawings.
- A 2764 service ROM for fitting in the BBC Microcomputer, containing the Bitstik graphic system.
Sam.

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pstnotpd
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Re: Bitstik roms. What do they do?

Post by pstnotpd » Mon Sep 06, 2010 6:20 pm

Yip, I've seen those.
Unfortunately I can't find the disks as ssd images.

And the manual doesn't seem to mention how to make use of the rom. It's all about the disk software.

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Samwise
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Re: Bitstik roms. What do they do?

Post by Samwise » Tue Sep 07, 2010 12:35 am

Is that not these over at TBL! along with the ROMs? If you rename the .dsk files to .ssd they should work.

Sam.

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Re: Bitstik roms. What do they do?

Post by mjforbes » Tue Sep 07, 2010 11:06 am

Samwise wrote:If you rename the .dsk files to .ssd they should work.
Sam.
A bit OT, but that's one for the FAQ on 'stardot' - some of the files on the "BBC Lives!" site are in '*.dsk' format. A quick rename to '*.ssd' will allow them to be used in BeebEm or B-Em. Also, a quick rename allows them to be transferred back to floppy or SD/CF for use on a proper machine.

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pstnotpd
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Re: Bitstik roms. What do they do?

Post by pstnotpd » Wed Sep 08, 2010 6:38 am

Indeed one for the FAQ. I got it booted but it's kinda hard to physically switch disks on a datacentre #-o

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Re: Bitstik roms. What do they do?

Post by retroclinic » Wed Sep 08, 2010 1:41 pm

pstnotpd wrote:Indeed one for the FAQ. I got it booted but it's kinda hard to physically switch disks on a datacentre #-o
Why? You've got 4 available, if that's not enough, it only take a few seconds to reimport an image?
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pstnotpd
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Re: Bitstik roms. What do they do?

Post by pstnotpd » Wed Sep 08, 2010 2:31 pm

The system, when booting up first loads some stuff from DFS drive 0: and then shows a message I should put another disk in drive 0: .....and press return.

The software seems littered with hard references to DFS physical drives, even in the rom images. Not nice.

So pun intended :D

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Re: Bitstik roms. What do they do?

Post by Faintbru » Sun Dec 04, 2011 4:17 pm

Hi Guys,

I just joined the board because I was one of the original programmers on the Bitstik II project. I was the graphic primitives specialist on BBC micros at a company called Ariadne Software, which Robocom came to have the Bitstick ported from the Apple ][. This was nearly 30 years ago, so I can't remember everything, but I'll do my best with any questions.

OK - the ROMs. If you have a Bitstick II ROM image it was coded and loaded to the master production EPROM by me. The problem we had with the Bitstick was that there was no end of memory (64K) on the tube, but almost nothing on the IO when the graphics mode went up. The point of the ROM is to hold the assembly routines that actually render the CAD image in the IO memory space. That's pretty much all it does.

Now direct references to disks and stuff. Even in those days Robocom was hysterical about illegal software copying. They paid us a fortune to develop the most comprehensive disc protection scheme possible, so there's all manner of coding eccentricities, hokey disc sectors and standards variation that derives specifically from that. To get a good Bitstik boot you need an original floppy disk, the ROM mapped into the IO (the BBC B doing the display) address space, the 6502 tube and the Bitstick itself. If you're using any kind of emulator, you're probably going to have obstacles to climb.

Just so you don't think I'm a stray nutter, if you have an original Bitstik II install disc, you'll find a program on there called 'The Mighty Chunderer' in the Basic code comments, which handles converting Bitstik I format data discs to the newer standard. My last name is Houbart, and I seem to think it's on the Basic code of that program. I can't help much with I, as that was before my time, I should be able to give you a pointer if you're trying II resuscitation .

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Re: Bitstik roms. What do they do?

Post by 1024MAK » Mon Dec 05, 2011 1:11 am

Faintbru wrote:Just so you don't think I'm a stray nutter...
It's alright, we welcome "stray nutter's", as long as they talk Beeb... =D> :lol: :wink:
Welcome
Mark

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