Search found 1368 matches

by RobC
Fri Apr 28, 2017 6:22 pm
Forum: general
Topic: Ceefax / Fastext Question
Replies: 9
Views: 869

Re: Ceefax / Fastext Question

What I don't know is whether the use of the coloured buttons drove the introduction of a page cache or whether it was something happenning separately that happenned to be well suited to this. As a kid, I had a teletext TV that didn't have Fastext but would cache any four pages you chose by pressing...
by RobC
Fri Apr 28, 2017 10:11 am
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 166
Views: 5019

Re: Palettemate / enhanced video ULA with 4096 colours

Sure - I'll mail you the board file.
by RobC
Fri Apr 28, 2017 8:49 am
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 166
Views: 5019

Re: Palettemate / enhanced video ULA with 4096 colours

The part number is EPM570T100C5N and I used a supplier from AliExpress: "Shenzhen IC Supermarket II". One word of caution though - I ordered 3 pieces but they sent me four with a note to say there was an extra "in case of problems"! Thanks for the offer of combining the order but...
by RobC
Fri Apr 28, 2017 7:16 am
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 166
Views: 5019

Re: Palettemate / enhanced video ULA with 4096 colours

Looks nice. What software did you use? It looks like CircuitMaker. If so, how did you find it? I used KiCad (and should also say thank you to Dominic for giving me lots of advice on how to use it). Will it work in all model b's, or will it need the track mod on some?Assuming I am remembering correc...
by RobC
Thu Apr 27, 2017 7:54 pm
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 166
Views: 5019

Re: Palettemate / enhanced video ULA with 4096 colours

Thanks. I've gone down to 2-layers with components only on one side to reduce prototype PCB costs and make assembling it easier but this has increased the form factor. I've also increased the minimum track size following some advice from Jason. It still fits in all machines except a Compact with Eco...
by RobC
Thu Apr 27, 2017 6:27 pm
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 166
Views: 5019

Re: Palettemate / enhanced video ULA with 4096 colours

Got the 2-layer PCB done today - just need to double check things before ordering some PCBs tomorrow...
videoNuLA.jpg
VideoNuLA
by RobC
Wed Apr 26, 2017 8:54 pm
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 166
Views: 5019

Re: Palettemate / enhanced video ULA with 4096 colours

Thanks Dominic - it was great to meet you and your family too. I'll have a look through that later this week - I'm starting to put together some ideas for the support ROM so this is very timely. I've been concentrating on the PCB so far this week: I've now designed a 2-layer board that's a bit bigge...
by RobC
Mon Apr 24, 2017 8:35 am
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 166
Views: 5019

Re: Palettemate / enhanced video ULA with 4096 colours

This looks really amazing. It's a pity you're not coming to Cambridge to show it off to a wider audience. Thanks. Unfortunately, having tried it once before, Cambridge is just that bit too far for me to do in a day. Plus it's our wedding anniversary that weekend and my wife isn't overly keen on spe...
by RobC
Sun Apr 23, 2017 9:29 pm
Forum: hardware
Topic: Odd RiscPC CMOS RAM issue
Replies: 8
Views: 84

Re: Odd RiscPC CMOS RAM issue

Not sure about CTRL-break/reset as I didn't try that. I would do *STATUS and the boards reported that the beep volume was set to quiet. I'd then do *CONF. LOUD and *STATUS would report that it had been changed. (However, I think this may only change the RAM copy of the settings as Daniel suggests.) ...
by RobC
Sun Apr 23, 2017 8:55 pm
Forum: hardware
Topic: Odd RiscPC CMOS RAM issue
Replies: 8
Views: 84

Re: Odd RiscPC CMOS RAM issue

Thanks both. I'd replaced the battery, checked the resistors and caps and had buzzed out the circuit so know that they are all okay. However, following Daniel's suggestion, I took a known good CMOS RAM chip off another RiscPC and fitted it to one of the problematic boards. I changed the beep volume ...
by RobC
Sun Apr 23, 2017 7:19 pm
Forum: hardware
Topic: Sockets at the back.
Replies: 2
Views: 100

Re: Sockets at the back.

Also the RS232 interface needs an internal upgrade fitted into ICs 5, 9, 13 and 14. It was an optional extra so may not be fitted on your machine.
by RobC
Sun Apr 23, 2017 7:09 pm
Forum: hardware
Topic: Odd RiscPC CMOS RAM issue
Replies: 8
Views: 84

Re: Odd RiscPC CMOS RAM issue

Thanks Daniel. Should have said that the circuits all buzz out (with resistors giving the correct values etc.). I replaced the crystal on one of the boards (to no avail) but didn't have any SMD CMOS RAM chips. Guess it's time to order some! Also, this is with RO 4.02. Is the brief red screen normal?
by RobC
Sun Apr 23, 2017 6:58 pm
Forum: hardware
Topic: Odd RiscPC CMOS RAM issue
Replies: 8
Views: 84

Odd RiscPC CMOS RAM issue

Armed with the Technical Reference Manual I picked up from the Charity Stall at Wakefield yesterday, I've been trying to sort through some RiscPC motherboards that I bought ages ago. All had their batteries replaced, were cleaned of corrosion and were fitted with new batteries as soon as I got them....
by RobC
Sun Apr 23, 2017 9:37 am
Forum: software: games
Topic: Addictive's Football Manager
Replies: 5
Views: 120

Re: Addictive's Football Manager

Not sure if there's an editor for FM - I played it for hours too BITD! The Micro User had a similar BASIC type-in game that I also used to play lots and you'd obviously be able to change the data with that. From memory, I think it was from September 1987 (the one after the Archimedes launch) but I c...
by RobC
Sat Apr 22, 2017 8:47 pm
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 22/4/17
Replies: 87
Views: 1977

Re: Wakefield RISC OS show 22/4/17

Had a great time today - it was good to meet up with people again and to see so much interest in the 8-bit and 32-bit scenes.

Special thanks to Simon/sydney for letting me share a table :D
by RobC
Sat Apr 22, 2017 8:44 pm
Forum: hardware
Topic: Palettemate / enhanced video ULA with 4096 colours
Replies: 166
Views: 5019

Re: Palettemate / enhanced video ULA with 4096 colours

Thanks everyone for all the encouragement - had a great time demoing this today! On progress, I've been concentrating on testing and PCB design so still need to finalise border control and resetting of the palette. I've now successfully tested the prototype in every model of Beeb and have got a PCB ...
by RobC
Fri Apr 21, 2017 5:47 pm
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 22/4/17
Replies: 87
Views: 1977

Re: Wakefield RISC OS show 22/4/17

No probs. Just need to pack everything now!
by RobC
Fri Apr 21, 2017 5:24 pm
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 22/4/17
Replies: 87
Views: 1977

Re: Wakefield RISC OS show 22/4/17

danielj wrote:Can I follow Jason in requesting an RGB-SCART if anyone would be able to bring one along tomorrow? Mine seems to have gone completely AWOL :(

I should be able to bring a spare. Do you need one for a TV or for a CM8833-type monitor? (i.e. one with resistors or without?)
by RobC
Fri Apr 21, 2017 4:49 pm
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 22/4/17
Replies: 87
Views: 1977

Re: Wakefield RISC OS show 22/4/17

Assuming I get up early enough and don't hit any traffic, I'll be there around 9:30am.
by RobC
Fri Apr 21, 2017 12:16 pm
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 22/4/17
Replies: 87
Views: 1977

Re: Wakefield RISC OS show 22/4/17

jbnbeeb wrote:Does anyone have an extra Beeb RGB -> SCART lead to bring along that they wouldn't mind me borrowing for saturday?

Sure - I'll bring one along with the monitor.
by RobC
Wed Apr 19, 2017 7:17 pm
Forum: hardware
Topic: BBC to VGA connector
Replies: 20
Views: 439

Re: BBC to VGA connector

The Compact uses double density (not HD) 3.5" disks. The capacity is usually marked as 720KB for PCs but the unformatted capacity is 1MB. They are usually blue. Any 3.5" disk that's marked "DSDD" or "2S2D" is usually okay. Anything that's marked "HD" or 1.44MB...
by RobC
Wed Apr 19, 2017 3:42 pm
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 22/4/17
Replies: 87
Views: 1977

Re: Wakefield RISC OS show 22/4/17

Will do.
by RobC
Mon Apr 17, 2017 10:49 am
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 22/4/17
Replies: 87
Views: 1977

Re: Wakefield RISC OS show 22/4/17

sydney wrote:Yes yes yes yes yes yes yes yes yes yes yes yes yes. Yes. I'm happy to let you have half of my table if you want.

That's pretty definite! A share of a table would be great - thanks. Happy to split costs.
by RobC
Mon Apr 17, 2017 7:36 am
Forum: upcoming and recent events & exhibitions
Topic: Wakefield RISC OS show 22/4/17
Replies: 87
Views: 1977

Re: Wakefield RISC OS show 22/4/17

I'm thinking of attending the show and can bring a spare CRT - I have various Acorn monitors with SCART or an Eizo multisync.

I could also bring my prototype enhanced video ULA board in a Beeb if people are interested in seeing it...
by RobC
Sun Apr 16, 2017 8:30 pm
Forum: hardware
Topic: A5000 keyboard problems
Replies: 7
Views: 117

Re: A5000 keyboard problems

Ahh right - that makes it more difficult! I may have a spare keyboard controller that I could post to you. I'll have a look for it tomorrow and will get back to you. EDIT: I've found a keyboard controller IC marked "Avon" but I believe that's for an A3000. Do you know the part number you'r...
by RobC
Sat Apr 15, 2017 8:30 pm
Forum: hardware
Topic: A5000 keyboard problems
Replies: 7
Views: 117

Re: A5000 keyboard problems

Whereabouts are you?

I have a working A5000 keyboard that I could loan you for testing but it's possible that others are closer...
by RobC
Sat Apr 15, 2017 7:19 pm
Forum: hardware
Topic: A5000 keyboard problems
Replies: 7
Views: 117

Re: A5000 keyboard problems

I'd have a look at the circuit diagram and buzz out all the relevant tracks from the keyboard connector through the keyboard controller and to the IOEB. If you've got a scope, check that IC5 (hex inverting Schmitt trigger) is doing what it should too. If you haven't found it already, the circuit dia...
by RobC
Thu Apr 13, 2017 6:48 am
Forum: off-topic
Topic: LOLPRICE
Replies: 2561
Views: 147611

Re: LOLPRICE

flaxcottage wrote:And it comes without batteries for this price!

That's more than it cost to buy a brand new A3000 in 1989!
by RobC
Wed Apr 12, 2017 11:12 am
Forum: general
Topic: Today I received.....
Replies: 3837
Views: 181392

Re: Today I received.....

paulv wrote:The official news that I'm 18 months cancer free :D

Great news :D
by RobC
Wed Apr 12, 2017 7:43 am
Forum: hardware
Topic: Original Beeb option : Model C 48K ( video ram partially shadowed in sideways area)?
Replies: 19
Views: 358

Re: Original Beeb option : Model C 48K ( video ram partially shadowed in sideways area)?

1024MAK wrote:Sorry, but the context I was writing this in, was that this would have been a possible feature of a follow on machine. Not the model B. See my earlier post.

My mistake - I hadn't clocked the last paragraph of your earlier post :oops:

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