Search found 421 matches

by IanB
Sat Jan 18, 2020 4:17 am
Forum: acorn atom and system
Topic: Acorn System/Atom Econet
Replies: 14
Views: 678

Re: Acorn System/Atom Econet

Tried that still no joy. It appears that the disk is a different format not DOS/DFS, if i try to EXEC any text file I get gobbledy-gook. I tried this myself today and managed to get it working with the 0.22 image after writing it with Omniflop so there is something wrong with the way you are writin...
by IanB
Wed Jan 15, 2020 11:50 pm
Forum: acorn atom and system
Topic: Acorn System/Atom Econet
Replies: 14
Views: 678

Re: Acorn System/Atom Econet

trev-ham wrote:
Tue Jan 14, 2020 6:04 pm
Obviously, I require some means of creating a FS3 blank disk.
Try formatting a blank disk on a BBC (both sides) under DFS then putting that disk into the System drive 1/3, running SBASIC (BBC BASIC on the System) and then loading/running the BBC BASIC "INIT13" program.
by IanB
Mon Jan 13, 2020 11:54 pm
Forum: acorn atom and system
Topic: Acorn System/Atom Econet
Replies: 14
Views: 678

Re: Acorn System/Atom Econet

I used File server III.22. The FS discs (40 DS) were mapped using MPINIT from FSII.14 (this is actually what I did originally but caused that error). That wouldn't work as FSIII is incompatible with FSII in both protocol and disk format (they were both changed to switch from 16 bit to 32 bit addres...
by IanB
Fri Jan 10, 2020 10:05 pm
Forum: acorn atom and system
Topic: Acorn System/Atom Econet
Replies: 14
Views: 678

Re: Acorn System/Atom Econet

Acorn File Server III.22 (does that mean a level 3?) No, it means Econet protocols V3. It's a level 2 file server but as mentioned above it doesn't really identify itself as such, just "Acorn File Server" as it was the only file server originally. The version posted by Bodie is Acorn File Server II...
by IanB
Fri Jan 10, 2020 2:24 am
Forum: acorn atom and system
Topic: Acorn System/Atom Econet
Replies: 14
Views: 678

Re: Acorn System/Atom Econet

in the beginning there were network primitives and a file server known as Level 1 - a basic file server where a library of files were accessible to anyone on the network, and there's level 2 which introduced a hierarchical file structure with user access control. If this is not totally correct plea...
by IanB
Sat Dec 28, 2019 3:36 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

I've added support for a few more machines: Camputers Lynx: capture6.png This one has a 3 bit TTL output like the beeb. Colour Genie: capture4.png This one uses TTL connections picked up internally. Tandy Micro Color Computer: (MC-10) capture2.png This one uses the new RGB/YUV interface with YUV sig...
by IanB
Sun Dec 15, 2019 10:37 pm
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 236
Views: 11742

Re: Atom Video to HDMI Adapter

hoglet wrote:
Sun Dec 15, 2019 10:29 pm
Is the new analog board working as expected then?
It ended up working in a slightly different way than I envisaged with the 6847 sources (I had to make one minor track cut and link and use different input signals) but after that change it works really well with everything I've tried so far.
by IanB
Sun Dec 15, 2019 10:26 pm
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 236
Views: 11742

Re: Atom Video to HDMI Adapter

I am wondering ......... will this Atom Video to HDMI adapter also work for a Dragon, or any other system with a 6847? The Dragon also has a 6847, only 8 colours in textmode. I just got the RGB/YUV interface board working with the dragon: dragon.jpg capture9.png I don't have any software to run on ...
by IanB
Sat Dec 14, 2019 2:16 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

Got my new issue 2 combined RGB and YUV boards back from JLC so I can now use it for analog RGB sources, 6847 YUV type sources and monochrome sources. Here it is working with the Amstrad CPC: rgb.jpg And an Atom: yuv.jpg It even works with the beeb / electron: beeb.jpg (It isn't require of course as...
by IanB
Mon Dec 02, 2019 7:47 pm
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 236
Views: 11742

Re: Atom Video to HDMI Adapter

oss003 wrote:
Mon Dec 02, 2019 6:52 pm
Nice job Ian, is that a screen with split palet mode?
Yes that's Dave's test software that switches between the two 6847 palettes half way.
by IanB
Mon Dec 02, 2019 7:44 pm
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 236
Views: 11742

Re: Atom Video to HDMI Adapter

Is the issue that you need different thresholds for Y and PA/PB? Yes Out of interest, what did your mods actually do? 1. Lift pin 14 of both U1 and U2 to isolate the Vsync and Sync inputs and then feed V and H sync from the Atom 10 way connector directly to the TTL header. 2. Lift Pins 2 & 9 of U2 ...
by IanB
Mon Dec 02, 2019 6:19 pm
Forum: acorn atom and system
Topic: Atom Video to HDMI Adapter
Replies: 236
Views: 11742

Re: Atom Video to HDMI Adapter

I've got the new Analog interface for the six bit version of RGB to HD working with the Atom using a few simple mods so I think the next issue of the analog PCB will have the ability to work with the Atom (and 6847 chips in general): The colours are wrong because a YUV signal is being sent to an RGB...
by IanB
Sat Nov 30, 2019 12:15 pm
Forum: hardware
Topic: Info please! Acorn's in-house large-memory 6502 co-pro
Replies: 99
Views: 5222

Re: Info please! Acorn's in-house large-memory 6502 co-pro

Could it be the mystery version of BASIC whose existence hoglet proposed ? I did a patch to the original version of HiBasic which did three things: 1. assemble the CMOS instructions 2. Generate an error when duplicate labels were used if OPT +8 3. Put the object code in the host memory space if OPT...
by IanB
Sat Nov 30, 2019 12:26 am
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

-B- wrote:
Fri Nov 29, 2019 11:35 pm
This might help...
ZX8301.pdf
Thanks, it was 10Mhz & 640 clock cycles so I created a new profile based on that, you can try it when the new software is released.
by IanB
Fri Nov 29, 2019 11:12 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

I have a couple but I’m not in the UK. I will be for Christmas though, so if you’d like me to lend you one.... That might be useful. I can probably create a profile with just some tech info although it would have to be connected to a real machine for the final tweaks. Do you know what pixel clock f...
by IanB
Fri Nov 29, 2019 6:36 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

-B- wrote:
Fri Nov 29, 2019 11:47 am
Have you tried the QL yet, with its famous overscan in monitor mode?
Unfortunately I don't have a QL but it looks like it has a standard RGB TTL output so it should work, it's just a matter of creating a profile.
Does anyone here have a QL?
by IanB
Wed Nov 27, 2019 6:05 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

Now working with the Spectrum:
capture2.png
by IanB
Wed Nov 27, 2019 4:44 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

The new boards came today:

new boards.jpg

I built a pair up:

built1.jpg
built2.jpg
built3.jpg

They fitted perfectly in the case:

installed.jpg

And worked perfectly:

capture88.png
capture89.png
by IanB
Tue Nov 19, 2019 3:11 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

Which DACs and Comparators is that using? The DAC is the TLC5620 and the comparators are the lower cost 40ns MAX9144. Actually the biggest problem with noise was the outputs of the DACs and that was cured by connecting a 100nf capacitor to ground on each output. As the MAX9144 is 14 pin compared to...
by IanB
Tue Nov 19, 2019 1:59 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

Im very much looking forward to seeing the analog frontend working. After some initial problems with noise due to insufficient decoupling, I finally got the breadboard prototype of the analog interface working: BREADBOARD.jpg And here are some results: capture20.png capture21.png capture16.png capt...
by IanB
Thu Nov 07, 2019 7:35 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

-B- wrote:
Thu Nov 07, 2019 8:14 am
Ah, you beat me to it. I am using your ZX81 circuit with the old version of the board...
That's very neat, I assume it works OK? (I was concerned that the extra heat inside the PI case might make the threshold adjustments a bit unstable.)
by IanB
Thu Nov 07, 2019 7:17 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

I fitted 330R termination resistors, and it can just about descriminate the three level RGB signals, due to the differeing thresholds of the 74LS08 buffer and the CPLD. That's a clever trick although it may not be reliably repeatable. Am I right in thinking that as well as plugging in to the 2x5 wa...
by IanB
Thu Nov 07, 2019 3:16 am
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

While I was waiting for the PCBs, I did some preliminary design on an analog interface add-on which should increase the number of old computers supported. The design uses some fast comparators and D to A converters to set the thresholds from the menus instead of the potentiometers used in my origina...
by IanB
Wed Nov 06, 2019 11:04 pm
Forum: hardware
Topic: PS/2 keyboard & mouse to Archimedes adapter MK II
Replies: 33
Views: 5648

Re: PS/2 keyboard & mouse to Archimedes adapter MK II

So both error lights come on when pressing record. The mouse and keyboard still don't respond after the recording has finished. (I can do a reset with windows key + break, which I don't think I could do before). Is it possible to disable to timeout?, the standard arc keyboard appears to handle inte...
by IanB
Wed Nov 06, 2019 9:21 pm
Forum: hardware
Topic: PS/2 keyboard & mouse to Archimedes adapter MK II
Replies: 33
Views: 5648

Re: PS/2 keyboard & mouse to Archimedes adapter MK II

It does look like interrupts are disabled (makes sense, as they are probably polling the A/D converter). With an original Arc keyboard the caps lock doesn't respond during recording. I found a possible problem where the protocol error flag wasn't being cleared on a restart which would cause an infi...
by IanB
Wed Nov 06, 2019 8:54 pm
Forum: hardware
Topic: PS/2 keyboard & mouse to Archimedes adapter MK II
Replies: 33
Views: 5648

Re: PS/2 keyboard & mouse to Archimedes adapter MK II

On a real Arc keyboard the mouse freezes during recording, but then moves again after the recording has finished. With the PS/2 adapter, when you click record, both error lights come on, and the mouse and keyboard won't work again until after a power cycle. Two leds means an error occurred with the...
by IanB
Wed Nov 06, 2019 7:11 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

Nice work! but it's only for Elk and PC, or it works with Micros and Masters too? Yes BBC, Master 128 and most Electrons. (I've just edited the post to make that a bit clearer) There may be an issue with some early Electrons as I had to remove the buffer Dave used to get his early Electron working ...
by IanB
Wed Nov 06, 2019 6:44 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 840
Views: 49121

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

I received my new six bit PCBs from JLC today: boards.jpg I built one up and it worked first time including self programming of the CPLD by the PI so no programmer was needed: (Shown with a PC lead for MDA, CGA and EGA) assembled.jpg This shows the underside with the new IDC header to mount the cabl...
by IanB
Sun Nov 03, 2019 9:44 pm
Forum: hardware
Topic: PS/2 keyboard & mouse to Archimedes adapter MK II
Replies: 33
Views: 5648

Re: PS/2 keyboard & mouse to Archimedes adapter MK II

IanS wrote:
Sat Nov 02, 2019 11:55 pm
Not a show-stopper, but was supprised that with only a mouse connected the mouse buttons don't work, it appears to need a keyboard connected to allow any button presses (keyboard or mouse) to register.
Here's V0.17 with the mouse button bug fixed:
arc2ps2-v0-17.zip
(12.65 KiB) Downloaded 10 times
by IanB
Sun Nov 03, 2019 2:21 am
Forum: hardware
Topic: PS/2 keyboard & mouse to Archimedes adapter MK II
Replies: 33
Views: 5648

Re: PS/2 keyboard & mouse to Archimedes adapter MK II

Pin 4 appears to have a fairly high input resistance. I tried adding a 4K7 pull-up, with a jumper to pull it low, but with just the resistor, the voltage on pin4 was only about 1.5V, which wasn't enough to register it as high. The prototyping board I used above had a 10K pullup on that line and I n...