Search found 439 matches

by myelin
Mon Oct 15, 2018 4:52 pm
Forum: hardware
Topic: Raspberry Pi to 1MHz bus interface
Replies: 17
Views: 329

Re: Raspberry Pi to 1MHz bus interface

Please put me down for two. Thank you!
by myelin
Fri Oct 12, 2018 5:18 pm
Forum: hardware
Topic: A3000 IC2 - keyboard/mouse controller
Replies: 3
Views: 135

Re: A3000 IC2 - keyboard/mouse controller

Ahhh, that makes a lot of sense, and explains what LK3 is for. I'd actually spotted that project by IanB but hadn't realized that it was a PS2-to-KART protocol converter :)
by myelin
Thu Oct 11, 2018 10:59 pm
Forum: hardware
Topic: A3000 IC2 - keyboard/mouse controller
Replies: 3
Views: 135

A3000 IC2 - keyboard/mouse controller

Hi all, I've just come into possession of a few sparingly-populated A3000 boards, two of which are missing IC2, the keyboard/mouse controller. I wonder if anybody here has made a modern replacement for this chip? It looks like it talks to the rest of the system via a two-wire asynchronous serial int...
by myelin
Tue Oct 09, 2018 10:18 pm
Forum: hardware
Topic: New hardware suggestion - Pi econet server
Replies: 43
Views: 1382

Re: New hardware suggestion - Pi econet server

Yes, the CPLD keeps track of where the stuffed bits need to be added/dropped and then the micro isn't clocked during the extra data bit so it is lost. On the transmit side the CPLD, being master, pauses the SPI clock while it sends an extra bit. To get this all to work, some logic is on the rising ...
by myelin
Fri Oct 05, 2018 7:22 pm
Forum: hardware
Topic: New hardware suggestion - Pi econet server
Replies: 43
Views: 1382

Re: New hardware suggestion - Pi econet server

The CPLD on my board does convert between SPI and econet by bitstuffing and unstuffing. On RX, it obtains byte sync by usng on the opening flags and the econet clock gets passed through to the SPI slave (USB microcontroller). The start/stop flags are used to create a /SS line. Very large econet fra...
by myelin
Thu Oct 04, 2018 5:02 pm
Forum: hardware
Topic: New hardware suggestion - Pi econet server
Replies: 43
Views: 1382

Re: New hardware suggestion - Pi econet server

This conversation gave me a bit of energy to pick up my own USB Econet project and get it a bit closer to working. It's still far far behind flynnjs's original one and gazzaD's Arduino Filestore , but the raw output side of it seems to be going now -- the microcontroller sends bytes to the CPLD, whi...
by myelin
Sun Sep 30, 2018 12:05 am
Forum: hardware
Topic: myelin’s Econet Hub
Replies: 24
Views: 1232

Re: myelin’s Econet Hub

Nice work Liam!
by myelin
Wed Sep 26, 2018 10:34 pm
Forum: general
Topic: Today I received.....
Replies: 4854
Views: 334412

Re: Today I received.....

A nice set of PRMs for RISC OS 2, to go with the RISC OS 3 PRMs living in my parents' attic back in New Zealand :)
risc os 2 PRMs sm.JPG
by myelin
Mon Sep 24, 2018 8:24 pm
Forum: hardware
Topic: New hardware suggestion - Pi econet server
Replies: 43
Views: 1382

Re: New hardware suggestion - Pi econet server

The USB Econet dongle works. But there's been lack of enthusiasm to finish the host software. We have something mostly working on Linux+Windows but none of those involved would attempt anything on riscos. I could make dongles available to anyone willing to commit to doing something on the host soft...
by myelin
Sun Aug 12, 2018 11:32 pm
Forum: introduce yourself
Topic: Hello from Palo Alto
Replies: 13
Views: 415

Re: Hello from Palo Alto

Hi neighbour! Did you see our display at the Computer History Museum last weekend (for the Vintage Computer Festival)? I'm in Mountain View, and 8bitkick is in San Jose, I believe. There's a small but growing group of us with Beebs and Electrons over here in Norcal :)
by myelin
Fri Aug 10, 2018 10:37 pm
Forum: general
Topic: Today I received.....
Replies: 4854
Views: 334412

Re: Today I received.....

Smaller (partial) surface mount 8-bit IDE podule. IMG_20180810_220808.jpg It fits vertically in an A30x0. IMG_20180810_220541_HDR.jpg Only one short that stopped it working first time, it was on the first resistor pack I fitted. (I still need to seriously improve my surface mount soldering skills. ...
by myelin
Fri Aug 10, 2018 10:32 pm
Forum: hardware
Topic: Raspberry Pi B+ compatible GPIO Extender 40-way Ribbon Cable Female-Male
Replies: 27
Views: 652

Re: Raspberry Pi B+ compatible GPIO Extender 40-way Ribbon Cable Female-Male

So your Pi works fine plugged directly into your Model B, and doesn't work when plugged into either the Model B or Master via the GPIO extender cable? You've checked that it's connected the right way around, but get garbage instead of the "Acorn TUBE 6502" header via the cable. I assume it's this ca...
by myelin
Tue Aug 07, 2018 8:55 pm
Forum: development tools
Topic: Deploy-and-run from PC to Beeb?
Replies: 33
Views: 874

Re: Deploy-and-run from PC to Beeb?

Looking in therefore, I think I see many in the retro computer world that appear to expend significant effort in bringing their Acorn environment into the modern age, or as Phillip phrased it, ‘ optimising their build pipeline ’, but then having got there, not really doing much more in the actual p...
by myelin
Tue Aug 07, 2018 5:22 pm
Forum: development tools
Topic: Deploy-and-run from PC to Beeb?
Replies: 33
Views: 874

Re: Deploy-and-run from PC to Beeb?

Being the one who originally suggested UPURSFS/HostFS, I should jump in here to confirm what MartinB just said! Standard UPURS is pretty bulletproof once you get your cable sorted out, and *UPLOAD will do most things you need, then *UPSSD and *UPDSD will let you upload entire disc images. So if you'...
by myelin
Mon Aug 06, 2018 9:26 pm
Forum: development tools
Topic: Deploy-and-run from PC to Beeb?
Replies: 33
Views: 874

Re: Deploy-and-run from PC to Beeb?

If you can get UPURSFS (HostFS:UPURS) running well, it lets you run binaries directly off an attached PC, using the UPURS bit-banged 115k2 serial port.
by myelin
Thu Aug 02, 2018 3:55 am
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 331
Views: 12236

Re: RGB to HDMI using a Pi Zero and a small CPLD

Finally set mine up, and it works very nicely with my Master 128. Thanks Dave! Now I can run three computers at VCF West rather than two :)
by myelin
Tue Jul 31, 2018 10:20 pm
Forum: acorn atom
Topic: Econet Card on Ebay
Replies: 13
Views: 489

Re: Econet Card on Ebay

Looks like it sold for £51! Way above what I was hoping for :)
by myelin
Sat Jul 28, 2018 11:34 pm
Forum: acorn atom
Topic: Acorn Atom on Ebay
Replies: 13
Views: 610

Re: Acorn Atom on Ebay

CMcDougall wrote:
Sat Jul 28, 2018 9:58 pm
atom econet card, 4 bids so far £13.50 +5pp....
https://www.ebay.co.uk/itm/Original-Iss ... 6016.l4276
Anyone else bidding on this? I'm very interested in it.
by myelin
Sat Jul 14, 2018 7:08 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 331
Views: 12236

Re: RGB to HDMI using a Pi Zero and a small CPLD

1920x1080 here!
by myelin
Wed Jul 11, 2018 5:30 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 331
Views: 12236

Re: RGB to HDMI using a Pi Zero and a small CPLD

I'd be very interested in one (HAT + cable, shipped to San Francisco). Really glad to see this project reaching this stage :) Thanks Dave!

I'm probably going to be switching this between machines, and mounting it behind a monitor, so can I have a 100cm cable please?
by myelin
Tue Jul 10, 2018 9:24 pm
Forum: acorn atom
Topic: New Atom owner (soon)
Replies: 9
Views: 463

Re: New Atom owner (soon)

The only problem is the Y/PA/PB signals are relatively low voltage swing and tri-level (with some redundancy). Figure 10 in the 6847 data sheet best explains this. In the FPGA I use the differential LVDS I/O cells rather than external comparators. Each of PA and PB uses a pair of LDVS I/O cells, wh...
by myelin
Sun Jul 08, 2018 6:56 am
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 331
Views: 12236

Re: RGB to HDMI using a Pi Zero and a small CPLD

hoglet wrote:
Sat Jul 07, 2018 1:13 pm
And lo and behold....
P1030968.JPG
(this was on an Issue 4 Elk)
Nice work! Looking forward to building up a few of these so I can have more than one machine with a display at once :)
by myelin
Sun Jul 08, 2018 6:55 am
Forum: acorn atom
Topic: New Atom owner (soon)
Replies: 9
Views: 463

Re: New Atom owner (soon)

8bitkick wrote:
Sun Jul 08, 2018 4:34 am
Until you get your MMC this might be useful. I just saw your post which prompted me to get in online...
Thank you! Yes, that'll be super useful! Are you bringing your Atom to VCF? There's a slight chance that mine might arrive in time...
by myelin
Sun Jul 08, 2018 2:41 am
Forum: acorn atom
Topic: New Atom owner (soon)
Replies: 9
Views: 463

Re: New Atom owner (soon)

What's you plan in terms of extensions? Not sure yet! AtoMMC2 seems like an excellent start. I like the look of your scan converter. Also, do you think your RGBtoHDMI hardware could be adapted to work here? I guess you would need comparators on the inputs...? I'm still figuring out how the whole Y/...
by myelin
Thu Jul 05, 2018 9:32 pm
Forum: acorn atom
Topic: New Atom owner (soon)
Replies: 9
Views: 463

New Atom owner (soon)

After staring at it on eBay for a couple of weeks, I finally cracked and bought the 200 euro Atom from backtoyourpast (pricey, but out of the Atoms I've seen whose owners will ship to the USA, it seemed bearable). So... I expect to be an Atom owner once it arrives in San Francisco :)
by myelin
Fri Jun 29, 2018 9:34 pm
Forum: hardware
Topic: Missing old/new Electron Expansions
Replies: 76
Views: 1471

Re: Missing old/new Electron Expansions

A couple of things got me thinking on various threads about what is not about for the Electron, a dredge of previous threads really. - With Daniel's freewifi for the serial port ... nowhere to plug it in on Electron ... and no serial port remakes - With Beebmasters Eco hubs .... dont think there wa...
by myelin
Fri Jun 22, 2018 11:24 pm
Forum: emulators
Topic: Econet for Arculator (and other emulators)
Replies: 13
Views: 786

Re: Econet for Arculator (and other emulators)

This does sound interesting, would be fun to connect a virtual arc to a virtual beeb over a virtual network :) Indeed! Hoping to do exactly that, and maybe have it use an USB Econet adapter (either my half-finished one, or flynnjs's one) as a bridge onto a real Econet. Not sure if that would play w...
by myelin
Fri Jun 15, 2018 4:39 pm
Forum: hardware
Topic: Multi-purpose podule with a Raspberry Pi
Replies: 8
Views: 401

Re: Multi-purpose podule with a Raspberry Pi

It looks like Circle (bare-metal Pi programming environment) has network, USB, and SD card drivers, plus some other possibly useful bits and pieces, so the approach of using the CPLD as a level shifter and doing everything in the Pi may actually work, as long as the drivers for current podules use s...