Search found 2152 matches

by RobC
Thu May 24, 2018 8:36 pm
Forum: hardware
Topic: BBC/Master Power Supply Adjustment
Replies: 11
Views: 255

Re: BBC/Master Power Supply Adjustment

There's a pot that adjusts the voltage on the side of the PSU. You can see it in a dismantled PSU here . The pot is the round black thing with a slot for a cross-head screwdriver. It's worth carefully checking that you have the right size screwdriver and have it in the right place before turning the...
by RobC
Thu May 24, 2018 8:22 pm
Forum: hardware
Topic: Risc PC CPU Oscillator/Crystal
Replies: 2
Views: 139

Re: Risc PC CPU Crystal

I've bought oscillators with that footprint from Surplectronics in the past.

They seem to have an 80MHz oscillator in stock but you'll need to check the footprint and voltage etc.
by RobC
Thu May 24, 2018 3:02 pm
Forum: software: other
Topic: Border tracing Mandelbrot generator for the Beeb
Replies: 71
Views: 5284

Re: Border tracing Mandelbrot generator for the Beeb

This being the case, you wouldn't even want to try to share the computation work - just have the co-pro doing the calculations, and host doing the plotting (via a custom WRCH implementation). I suspect the host might even still be the bottleneck in this case! Definitely - just let the native ARM co...
by RobC
Wed May 23, 2018 9:37 pm
Forum: software: other
Topic: Plotmate ROM
Replies: 2
Views: 126

Re: Plotmate ROM

Most likely it's the control ROM for the Linear Graphics Plotmate A3 plotter.

More info here.

The plotter itself is fairly rare but I have seen them come up on eBay once in a while.
by RobC
Wed May 23, 2018 6:50 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

Thanks Marcus.

I think the MOS 3.50 issue was that I was using OSARGS to read the command line (from code taken from Sprow's ARMTDMI examples). I've now switched to using OS_GetEnv. I'll put the same fix into my other emulators at some point.
by RobC
Wed May 23, 2018 2:23 pm
Forum: hardware
Topic: BeebSID
Replies: 930
Views: 85280

Re: BeebSID

RobC - do you have parts list what is needed? I am not so great with soldering iron :lol: I'm making one up for trixster - I can order the parts and make one up for you too if you like? I don't have any SIDs though so you'd have to source one yourself... The parts come to about £20 - the PCBs are f...
by RobC
Wed May 23, 2018 12:19 pm
Forum: hardware
Topic: BeebSID
Replies: 930
Views: 85280

Re: BeebSID

I think RobC has some PCBs still? Just checked - I now only have four PCBs here but 3 are spoken for (bagpuss x 2 and trixster x 1) and I had intended to keep one for myself. However, somewhere I definitely have another bare PCB from the initial run but it has already evaded several of my attempts ...
by RobC
Tue May 22, 2018 7:21 pm
Forum: for sale / freebies
Topic: BeebSCSI mini
Replies: 165
Views: 13346

Re: BeebSCSI mini

flibble wrote:Does anyone know of a source of 34way M to F ribbon cables? I want to fit mine inside my master.
I fitted the 34-way version of these to an old floppy cable.
by RobC
Tue May 22, 2018 5:44 pm
Forum: hardware
Topic: Master Ram Board or Second Processors.
Replies: 4
Views: 272

Re: Master Ram Board or Second Processors.

One thing that puts me off the MRB is the need to unsolder the CPU. I can do some soldering but I’m not the best and I don’t won’t to muck it up. Might be worth seeing if there's a hacker/maker group near to you. If so, it's likely that someone there will have the necessary skills to desolder the C...
by RobC
Mon May 21, 2018 2:56 pm
Forum: hardware
Topic: Advice on internal Datacentre 1MHz bus cable installation?
Replies: 8
Views: 286

Re: Advice on internal Datacentre 1MHz bus cable installation?

VectorEyes wrote:Are there recommended tools for carefully hacking sections out of old plastic computer cases?
I used a dremel type tool (actually a Proxxon) when I modded my A4 case. It's good for removing large amounts of plastic quickly and then you can tidy the edges up with a file.
by RobC
Mon May 21, 2018 2:01 pm
Forum: hardware
Topic: Advice on internal Datacentre 1MHz bus cable installation?
Replies: 8
Views: 286

Re: Advice on internal Datacentre 1MHz bus cable installation?

I think Mark usually puts some card between the cable and the underside of the PCB and sticks the cable to the outside of the card using a glue gun (or similar). This prevents any of the legs/sharp bits of the the PCB from damaging the cable. I copied this when mounting my Pi co-pro inside my model B.
by RobC
Sat May 19, 2018 3:06 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

I've created a new version of SpectROM that fixes a few issues with the keyboard handling (thanks JGH!) and adds support for loading and saving .tap tape files. It also now works under MOS 3.50 on the Master (at least from my DC).

Enjoy!
by RobC
Fri May 18, 2018 7:09 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

marcusjambler wrote:Assuming Native ARM required.

They look to work :
*ZXINIT runs and goes back to prompt
*ZXSCREEN changes mode and re-maps the characters and goes back to prompt.
Thanks - I'll have to dig my 3.50 ROM out as it seems they are working correctly.
by RobC
Thu May 17, 2018 8:58 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

I'll look into that - it hasn't been tested on MOS 3.50 as I don't have a machine with it in (I do have the ROM somewhere though!).

Could you try *SRLOADing SPROM and then doing *ZXINIT followed by *ZXSCREEN please? It would be useful to know if it hangs at either point.
by RobC
Thu May 17, 2018 8:32 pm
Forum: hardware
Topic: Simultaneous internet & mass storage solutions for the A3010
Replies: 27
Views: 853

Re: Simultaneous internet & mass storage solutions for the A3010

I'll dig the code off my RiscPC once I've put it back together (I'm in the process of combining two machines into one). If I haven't posted it by the weekend, feel free to PM me a reminder! As I never managed to get the transfer speeds up to acceptable levels (and so never tidied the code up), it's ...
by RobC
Thu May 17, 2018 6:21 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

Just tested the Easter Egg RC with BeebSCSI and it's all working now :D =D> =D>
by RobC
Thu May 17, 2018 4:46 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

Thanks Dave - will do. Will probably have to wait until after the kids go to bed now though :(
by RobC
Thu May 17, 2018 4:10 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

Thanks JGH - I managed to find my serial cable and have confirmed that RAMFS is using transfer types 0 & 1. Looking at the co-pro memory using the built-in *MEM command (thanks Dave!), it looks like ZXSPEC isn't being loaded properly. The first half of the file (approximately) looks okay but the sec...
by RobC
Thu May 17, 2018 3:19 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

Thanks Dave.

Does anyone know what RAMFS on the DC uses? I'm guessing that it has a similar issue but I can't find my USB->serial cable to check with a debug build of the Pi co-pro!
by RobC
Thu May 17, 2018 12:58 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

Just had a thought - earlier in this thread, we mentioned that the native ARM core doesn't support 256-byte transfers through TUBE register 3. Does ADFS 1.50 use these for *LOAD etc.? (Although, thinking about it, it seems odd that ADFS 1.53 wouldn't do the same and it works happily on my DC under t...
by RobC
Thu May 17, 2018 12:36 pm
Forum: hardware
Topic: Simultaneous internet & mass storage solutions for the A3010
Replies: 27
Views: 853

Re: Simultaneous internet & mass storage solutions for the A3010

The plipbox is going to take some work - we need a PLIP driver for RISC OS, and that means writing one from scratch...... When I wrote a RISC OS driver for the CP2201 , I used the EtherY driver as a staring point. Once you've got functions to initialise the device and send and receive packets, it's...
by RobC
Thu May 17, 2018 12:24 pm
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

jgharston wrote:*MDUMP on the Tube Utilities disk and BBC Utilities Disk...
Many thanks - I'll do some more investigation later today.
by RobC
Thu May 17, 2018 9:47 am
Forum: hardware
Topic: SpectROM - Speccy emulator for the Pi co-pro
Replies: 153
Views: 6620

Re: SpectROM - Speccy emulator for the Pi co-pro

Finally managed to find some time to get my BeebSCSI up and running and I have replicated Marcus's hanging issue. However, I don't think it's anything to do with SpectROM as BAS135 and my ZX81 and Jupiter Ace emulators also hang when loaded from BeebSCSI (or the DC's RAMFS). All work correctly on my...
by RobC
Mon May 14, 2018 4:40 pm
Forum: hardware
Topic: Cheap web-modem for the beeb/master (and arc if ya like!)
Replies: 62
Views: 1919

Re: Cheap web-modem for the beeb/master (and arc if ya like!)

Andy1979 wrote:It's a shame my Master Compact is lacks the serial upgrade to make use of this...
Mark@Retroclinic has one upgrade kit still available on eBay.
by RobC
Fri May 11, 2018 3:02 pm
Forum: programming
Topic: RISCPC accessing parallel port in BASIC
Replies: 5
Views: 201

Re: RISCPC accessing parallel port in BASIC

There's some info on how to use the SYS command here . From memory, it's fairly straightforward once you get used to it but it's years since I did any serious BASIC programming on RISC OS. Might be worth playing with something like OS_Plot just to get started as it's like using the BASIC PLOT command.
by RobC
Fri May 11, 2018 11:50 am
Forum: programming
Topic: RISCPC accessing parallel port in BASIC
Replies: 5
Views: 201

Re: RISCPC accessing parallel port in BASIC

Have to admit that this isn't something I've done but the RISC OS Programmer's Reference Manual suggests that the Parallel_Op SWIs allow you to access the parallel port registers. You can access the OS SWI calls from BASIC using the SYS command.
by RobC
Thu May 10, 2018 8:52 pm
Forum: software: classic games
Topic: Nula Elite
Replies: 6
Views: 433

Re: Nula Elite

Are they 'lit' and shaded or a mix of colours? There's no lighting going on - Nick's code uses mode 5 so there aren't enough colours available to shade each face separately. If I could get it running in mode 2 then it would be doable. Your next project: Solid 3d Elite for the Beeb....?! I'd love to...
by RobC
Thu May 10, 2018 5:39 pm
Forum: software: classic games
Topic: Nula Elite
Replies: 6
Views: 433

Re: Nula Elite

That looks good. I had a modified version of Nick Jameson's Beeb3D demo running at Wakefield to show off some Elite ships in solid 3D with enhanced palettes: cobra.jpg viper.jpg They obviously look better when they're spinning! Given more time, I'd like to try writing a 16-colour mode 2 version for ...
by RobC
Thu May 10, 2018 6:36 am
Forum: hardware
Topic: A blitter for the beeb?
Replies: 59
Views: 4254

Re: A blitter for the beeb?

Well done :D =D> =D>

Disk error #26 has come up on here before - it's caused by the '*' as FLEX doesn't understand it.
by RobC
Sun May 06, 2018 3:12 pm
Forum: hardware
Topic: BeebSID and 1MHz bus silence
Replies: 2
Views: 230

Re: BeebSID and 1MHz bus silence

Glad you've got this sorted :D =D>