Search found 707 matches

by cmorley
Mon Jan 21, 2019 3:23 pm
Forum: hardware
Topic: A bit of fun: Which version of BBC Micro is the best?
Replies: 29
Views: 589

Re: A bit of fun: Which version of BBC Micro is the best?

The correct answer is of course the B. Of course this has nothing to do with me having half a dozen for sale :roll:
by cmorley
Sun Jan 20, 2019 6:06 pm
Forum: for sale / freebies
Topic: New A3000 4MB memory
Replies: 24
Views: 1552

Re: New A3000 4MB memory

Everyone who wanted RAM should now have it. If anyone wants some then get in touch sooner rather than later. I'm going to start listing the remaining stock on a famous auction site.
by cmorley
Sun Jan 20, 2019 5:49 pm
Forum: upcoming and recent events & exhibitions
Topic: ABUG SOUTH 18 to 20 January 2019 (Hampshire) BOOKING THREAD
Replies: 124
Views: 4607

Re: ABUG SOUTH 18 to 20 January 2019 (Hampshire) BOOKING THREAD

Splendid weekend. It was great to see familiar faces and some new ones. Many thanks to Robert for organising this event again. :)
by cmorley
Wed Jan 16, 2019 9:01 am
Forum: hardware
Topic: Romcs* observations
Replies: 5
Views: 199

Re: Romcs* observations

1024MAK wrote:
Wed Jan 16, 2019 8:03 am
Note that I have not looked at the schematics to see how Acorn actually did this in any Arcs.
On the A3000 the ROM ~CS comes from the MEMC and ~OE is tied to ground.
by cmorley
Mon Jan 14, 2019 11:25 am
Forum: hardware
Topic: POLL: How much Sideways RAM?
Replies: 20
Views: 493

Re: POLL: How much Sideways RAM?

Kazzie wrote:
Mon Jan 14, 2019 11:16 am
I had to look it up myself. It's shadow RAM hiding in the OS ROM's address space. See http://www.boobip.com/hardware/osram
Original forum thead here: viewtopic.php?f=3&t=13147&hilit=osram
by cmorley
Sun Jan 13, 2019 7:35 pm
Forum: hardware
Topic: BBC Master grumpy sideways RAM detection
Replies: 39
Views: 495

Re: BBC Master grumpy sideways RAM detection

It's a shame you're not ABUGing next weekend. Perhaps you could ask someone from Manchester who is going to bring it down & hoglet to do a log?
by cmorley
Sun Jan 13, 2019 3:12 pm
Forum: hardware
Topic: POLL: How much Sideways RAM?
Replies: 20
Views: 493

Re: POLL: How much Sideways RAM?

Everyone needs some OSRAM :) Execute code from one bank and use the other bank for data without aby bank switching 8) . Make the C64 jealous. Plus you can rewrite the 6502 vectors at FFFA, C, E I could probably do a cost reduced (less fiddly to assemble) one or self assembly kit... all it is waiting...
by cmorley
Sun Jan 13, 2019 1:22 pm
Forum: hardware
Topic: New 65C02/W65C816 copro
Replies: 94
Views: 7346

Re: New 65C02/W65C816 copro

I made another adapter board to see what I could get out of the WDC65C02 at 5v. A mod or two later this specimin is running at 33MHz from the BBC PSU. It'd go faster from an external & overvolt it a bit. Still not too shabby! Mandatory BASIC2 speed test results. It seems stable too. BBC BASIC CPU Ti...
by cmorley
Sat Jan 12, 2019 12:34 pm
Forum: upcoming and recent events & exhibitions
Topic: ABUG SOUTH 18 to 20 January 2019 (Hampshire) BOOKING THREAD
Replies: 124
Views: 4607

Re: ABUG SOUTH 18 to 20 January 2019 (Hampshire) BOOKING THREAD

Does anyone want me to bring anything specific? I'll pop a selection of my upgrades in the car just in case. I have another twin cumana floppy drive too I need to sell on, it is in great condition cosmetically. I also have a bunch of rather tidy Bs too so if anyone wants a smart B then 8) Is the eco...
by cmorley
Tue Jan 08, 2019 3:58 pm
Forum: off-topic
Topic: Xilinx lawyers
Replies: 15
Views: 466

Re: Xilinx lawyers

Both the USA and EU have fair use provisions.
by cmorley
Tue Jan 08, 2019 10:42 am
Forum: for sale / freebies
Topic: New A3000 4MB memory
Replies: 24
Views: 1552

Re: New A3000 4MB memory

Now Christmas is over until next December November October I have built up some batch 2 PCBs. So if anyone else wants one of these A3000 RAM boards get in touch. I'll put the rest up for sale on a famous auction site. Batch 2 is it - I won't make anymore after that because I don't think there is the...
by cmorley
Tue Jan 08, 2019 8:36 am
Forum: off-topic
Topic: Xilinx lawyers
Replies: 15
Views: 466

Re: Xilinx lawyers

No-one has said anything outrageous (so no-one take offence at me saying this, please) but it feels like it is getting a little heated in here ... Sorry, I'm not being confrontational. I would like to know why this would not be fair use it seems textbook - educational video on generic VHDL programm...
by cmorley
Tue Jan 08, 2019 8:11 am
Forum: off-topic
Topic: Xilinx lawyers
Replies: 15
Views: 466

Re: Xilinx lawyers

Of course it is a rant.

Please explain at least one reason why this could be trademark infringement and not fair use.
by cmorley
Mon Jan 07, 2019 10:44 pm
Forum: off-topic
Topic: Xilinx lawyers
Replies: 15
Views: 466

Re: Xilinx lawyers

Fair use. Comparing Xilinx to Altera is standard for a any FPGA related video.

If you misrepresent the company etc then yes... but using the Xilinx logo to represent Xilinx in a video? Fair use.

edit: pesky typos
by cmorley
Mon Jan 07, 2019 5:34 pm
Forum: off-topic
Topic: Xilinx lawyers
Replies: 15
Views: 466

Xilinx lawyers

An interesting video by Robert Feranec about Xilinx's recent behaviour... I'd love to know the motiviation Xilinx have but we never will I suppose. I wonder how long until Dave Jones (EEVBlog) does a video on this? https://www.youtube.com/watch?v=swVuqG9-H0E Edit: I wonder how long it'll be until th...
by cmorley
Mon Jan 07, 2019 1:42 pm
Forum: hardware
Topic: "Arcflash" A3000/A3xx/A4xx/A5xx/A5000 in-system programmable ROM -- any interest?
Replies: 69
Views: 2001

Re: A3000 in-system programmable ROM -- any interest?

Some Kickstart switchers on the Amiga simply hook reset (and row/col from keyboard matrix) then press key & reset to switch OS. Or count multiple resets in within 1s say and change OS. Needs a reset signal flylead but is simple to use/comprehend.
by cmorley
Mon Dec 24, 2018 8:57 pm
Forum: off-topic
Topic: Cleaning PCBs
Replies: 24
Views: 1369

Re: Cleaning PCBs

I dry boards at 120C on fan. 15 mins check them and another 15 mins. Works a treat especially for trapped moisture in connectors or under ICs.
by cmorley
Wed Dec 19, 2018 11:30 am
Forum: hardware
Topic: A3000 logic analyzer project
Replies: 13
Views: 606

Re: A3000 logic analyzer project

Yes 74LVC1G17GV from Nexperia IIRC
by cmorley
Tue Dec 18, 2018 8:26 am
Forum: hardware
Topic: A3000 logic analyzer project
Replies: 13
Views: 606

Re: A3000 logic analyzer project

Don't check it against a Cumana memory expansion... they got it wrong. Which is why they fit so poorly!
by cmorley
Tue Dec 18, 2018 7:30 am
Forum: hardware
Topic: A3000 logic analyzer project
Replies: 13
Views: 606

Re: A3000 logic analyzer project

If you want to buffer the A3000 MEMC lines then you'll need a buffer with 5V CMOS input threshold Vil not TTL like with LVC245 - else it will buffer the glitches. It is only the memc lines you would need to buffer - so 11 signals IIRC. Personally I wouldn't bother & I'd double register them at a hig...
by cmorley
Fri Dec 14, 2018 11:37 am
Forum: hardware
Topic: New A3000 4MB memory
Replies: 71
Views: 3207

Re: New A3000 4MB memory

Hopefully most people will have got their boards from batch 1 by now. Feel free to post positive or negative comments & photos! I've done extensive testing with it and it seems great.
by cmorley
Mon Dec 10, 2018 8:05 am
Forum: for sale / freebies
Topic: New Model B upgrades EEPROM, SRAM, adapters etc (BooBip)
Replies: 10
Views: 1379

Re: New Model B upgrades EEPROM, SRAM, adapters etc (BooBip)

Bump. All still current & in stock.
by cmorley
Sat Dec 08, 2018 8:57 pm
Forum: general
Topic: Remarkable videos recently posted on Youtube
Replies: 189
Views: 20726

Re: Remarkable videos recently posted on Youtube

algenon_iii wrote:
Sat Dec 08, 2018 8:08 pm
BBC Micro restoration from down under, most remarkable thing is the "replacement" PSU
https://www.youtube.com/watch?v=bC6h1rssuUI
That and it being what looks like a USA spec (or German?!) machine.
by cmorley
Fri Dec 07, 2018 4:05 pm
Forum: general
Topic: Today I received.....
Replies: 4958
Views: 356700

Re: Today I received.....

I may have over ordered on the right angle pin headers...
Photo0843.jpg
by cmorley
Fri Dec 07, 2018 1:13 pm
Forum: hardware
Topic: New A3000 4MB memory
Replies: 71
Views: 3207

Re: New A3000 4MB memory

Batch 1 ready for final test and shipping :)
Photo0838.jpg
by cmorley
Thu Dec 06, 2018 9:36 pm
Forum: for sale / freebies
Topic: New A3000 4MB memory
Replies: 24
Views: 1552

Re: New A3000 4MB memory

Issue 3 ( #-o ) boards tested good & batch one is being built and cleaned.

I'll PM people on the list.

I have more chips and will be ordering more blank PCBs so if you want one then get your name on the batch 2 list. Once they are gone I won't be making anymore...
by cmorley
Thu Dec 06, 2018 9:32 pm
Forum: hardware
Topic: New A3000 4MB memory
Replies: 71
Views: 3207

Re: New A3000 4MB memory

Ian has been busy testing and reports back zero errors! We've called it fixed now.

I'll update the sale thread. Batch one is built up, I have 11 boards in total (which I think is the exact number). I'll order more blank PCBs soon so batch 2 early/mid January I think.
by cmorley
Thu Dec 06, 2018 3:43 pm
Forum: introduce yourself
Topic: Greeting
Replies: 12
Views: 601

Re: Greeting

Welcome! :D
by cmorley
Tue Dec 04, 2018 3:25 pm
Forum: hardware
Topic: New A3000 4MB memory
Replies: 71
Views: 3207

Re: New A3000 4MB memory

The boards arrived today so I built one up to start testing. So far so good. I'll post one to IanS to see if it works in his computer.

Top:
Photo0836.jpg
Bottom:
Photo0833.jpg
by cmorley
Sat Nov 24, 2018 7:22 am
Forum: hardware
Topic: New A3000 4MB memory
Replies: 71
Views: 3207

Re: New A3000 4MB memory

Update: (Latest) PCBs are on their way from China :) They usually take about a week airmail.