Search found 21 matches

by noggin
Fri Dec 07, 2018 8:31 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 41318

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

I notice quite a lot of references to HDMI 1.0 limits. Is this for a specific reason? AIUI the Pi can go quite a lot further than HDMI 1.0 pixel clock limits should you need it to. I don't know about Zeroes but my Pi 3B+ happily does a 297MHz Pixel Clock to deliver an HDMI 1.4 3840x2160/30Hz RGB 8-b...
by noggin
Fri Nov 30, 2018 10:54 pm
Forum: hardware
Topic: John Kortink's BBC HDMI
Replies: 29
Views: 2160

Re: John Kortink's BBC HDMI

:arrow: Err, use DVI-D and tell users to get and use a DVI-D - HDMI Adapter (DVI-D 25 Pin M - HDMI 19 Pin F) Wikipedia says this... DVI and HDMI compatibility HDMI is a newer digital audio/video interface developed and promoted by the consumer electronics industry. DVI and HDMI have the same electr...
by noggin
Sun Jun 10, 2018 11:48 am
Forum: general
Topic: Acorn machines in the movies / TV
Replies: 42
Views: 4990

Re: Acorn machines in the movies / TV

Believe it or not - that's my Archimedes monitor :) I was paid for the day (my 16th Birthday!) to supervise the Archimedes and show the actors how to run the programme (I didn't write it - but I did modify it to make it easier to cue and recue (it just used the space bar to change from memory). It ...
by noggin
Mon Jun 04, 2018 12:22 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 41318

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

You beat me to suggesting a Weston deinterlacer - but I suspect the grunt required may put it out of reach? I don't think there is any way we will be able to implement any kind of advanced deinterlacing in software on the ARM. There just isn't the spare time, or the spare memory bandwidth. I think ...
by noggin
Mon Jun 04, 2018 12:29 am
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 41318

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

Bob does reduce the effective vertical resolution a bit but not by half and it does introduce interlace twitter (like a real CRT). This is a very late reply, but as nobody else has done so it's probably appropriate to point out that the BBC-designed 'Weston' de-interlacer (a static spatio-temporal ...
by noggin
Mon May 21, 2018 9:52 pm
Forum: general
Topic: Acorn machines in the movies / TV
Replies: 42
Views: 4990

Re: Acorn machines in the movies / TV

Found one! Doctor Who: Silver Nemesis (1988). Nazis hiding in South America use an Archimedes for calculating the return destination of a meteorite conveying a Time Lord super-weapon. vlcsnap-2017-11-08-21h21m13s534.png vlcsnap-2017-11-08-21h21m00s242.png Believe it or not - that's my Archimedes mo...
by noggin
Tue Oct 10, 2017 8:49 pm
Forum: hardware
Topic: Beeb FPGA
Replies: 498
Views: 41907

Re: Beeb FPGA

Thanks for that info Dave - will be running Windows.
by noggin
Tue Oct 10, 2017 1:10 pm
Forum: hardware
Topic: Beeb FPGA
Replies: 498
Views: 41907

Re: Beeb FPGA

hoglet wrote: 2. Download the BeebFPGA bitstream to FPGA RAM (bbc_micro_de1.sof) using the Altera Programmer software
Dave
Thanks Dave

Is the Altera Programmer Software called Quartus II - or is there another utility? I’ve got the Control Panel software from a download from the Terasic site.
by noggin
Tue Oct 10, 2017 12:35 pm
Forum: hardware
Topic: Beeb FPGA
Replies: 498
Views: 41907

Re: Beeb FPGA

Strange that as all proper HDMI monitors must support 576p and 576i. I am not sure if the pixels on the beeb can fit on a 576i mode with 1:1 pixels however? Sadly not the case - it's only European HDTVs that mandate HDMI 50Hz support - as part of the 'HD Ready' and 'HD 1080p' licensing (was EICTA n...
by noggin
Tue Oct 10, 2017 12:29 pm
Forum: hardware
Topic: Beeb FPGA
Replies: 498
Views: 41907

Re: Beeb FPGA

Strange that as all proper HDMI monitors must support 576p and 576i. I am not sure if the pixels on the beeb can fit on a 576i mode with 1:1 pixels however? Sadly not the case - it's only European HDTVs that mandate HDMI 50Hz support - as part of the 'HD Ready' and 'HD 1080p' licensing (was EICTA n...
by noggin
Tue Oct 10, 2017 11:49 am
Forum: hardware
Topic: FleaFPGA Ohm board and BBC hardware 'emulation'?
Replies: 3
Views: 662

Re: FleaFPGA Ohm board and BBC hardware 'emulation'?

Thanks all - I have a BlackIce board coming from Ken, but the HDMI output from the FleaFPGA Ohm seemed like a nice addition (though I realise some modes are a pain to get to output in a 720x576 or 1440x576 pixel-doubled SD 50Hz HDMI resolution - and would probably need a nice horizontal multi-tap fi...
by noggin
Mon Oct 09, 2017 10:13 am
Forum: hardware
Topic: FleaFPGA Ohm board and BBC hardware 'emulation'?
Replies: 3
Views: 662

FleaFPGA Ohm board and BBC hardware 'emulation'?

Just saw this new FPGA board https://www.indiegogo.com/projects/fleafpga-ohm-fpga-experimenter-board-arduino/x/12560007#/ from the guy behind previous Flea designs - which I think some here are familiar with? It's HDMI not VGA (which could cause some issues with BBC correct aspect-ratio video I susp...
by noggin
Sun Oct 08, 2017 9:27 am
Forum: hardware
Topic: Beeb FPGA
Replies: 498
Views: 41907

Re: Beeb FPGA

Strange that as all proper HDMI monitors must support 576p and 576i. I am not sure if the pixels on the beeb can fit on a 576i mode with 1:1 pixels however? Sadly not the case - it's only European HDTVs that mandate HDMI 50Hz support - as part of the 'HD Ready' and 'HD 1080p' licensing (was EICTA n...
by noggin
Fri Sep 15, 2017 10:07 pm
Forum: hardware
Topic: Beeb FPGA
Replies: 498
Views: 41907

Re: Beeb FPGA

From memory, 576i25 was originally not going to be catered for in the HDMI spec (which is very closely linked to DVI) as the pixel clock was too low. Instead the aim was for 'SD" devices to run at 576p50 instead (indeed Sky HD boxes in AUTO mode output 576p not 576i when tuned to SD broadcasts). How...
by noggin
Mon Sep 04, 2017 4:02 am
Forum: hardware
Topic: VT Clock Rom
Replies: 3
Views: 539

Re: VT Clock Rom

Yes - because computers like the BBC Micro (and Commodore Amiga) would output a standard PAL 625 composite signal, they were a good way of generating an ident clock for VTRs in broadcast edit suites. (Dedicated broadcast VT Clock generators from companies like Courtyard were more expensive than a BB...
by noggin
Fri Aug 25, 2017 11:04 am
Forum: hardware
Topic: VP415 laser disc calibration
Replies: 2
Views: 551

Re: VP415 laser disc calibration

I can't help with the specifics of the Laser Disc Player - but drop out compensators usually used a line delay (analogue CCD line store or digital via an ADC+line store+DAC) When the playback system detected a drop in signal/absence of video signal (on VTRs this was usually a drop in RF - not sure a...
by noggin
Thu Aug 24, 2017 9:54 am
Forum: hardware
Topic: BBC B with genlock card
Replies: 23
Views: 2464

Re: BBC B with genlock card

Yes - a Genlock card for a BBC Micro or Archimedes will just ensure that the video output of the BBC is properly synchronised with the reference input it is genlocked to. This is to allow it to be fed into a studio vision mixer, for clean cutting with other cameras, or fed to an in-vision monitor th...
by noggin
Tue Aug 15, 2017 12:24 pm
Forum: hardware
Topic: BBC B with genlock card
Replies: 23
Views: 2464

Re: BBC B with genlock card (poorly)

Replaced the system VIA. Now works (but only with the genlock card fitted). There is a ROM in it: DMTER54. Terminal Program for Rank-Cintel/BBC Slide File Only works on OS 1.0/1.2 9600 baud transmit/receive Written by David Markie Studio Engineering TVC 20/9/85 Edited and modified by Paul Robinson ...
by noggin
Fri Aug 04, 2017 12:46 am
Forum: hardware
Topic: Domesday86 Project
Replies: 82
Views: 6457

Re: Domesday86 Project

(As a side note - I wonder if the original 1" tape used to master the discs was transferred in the BBC's archive project. That would be on both Digtal Betacam and uncompressed SD 601 on LTO tape - in component 4:2:2 format decoded via a BBC TRANSFORM PAL decoder - the highest quality PAL decoder av...
by noggin
Thu Aug 03, 2017 4:32 pm
Forum: hardware
Topic: Domesday86 Project
Replies: 82
Views: 6457

Re: Domesday86 Project

The genlocking and video mixing isn't an issue at this stage; the intent is purely to capture the RF analogue data from the laserdisc. Once that's done it will be post-processed back into it's component parts, namely: * Video (frame by frame lossless since it's mainly still images) * Audio (two cha...
by noggin
Mon Jul 17, 2017 3:20 pm
Forum: hardware
Topic: Domesday86 Project
Replies: 82
Views: 6457

Re: Domesday86 Project

The Domesday86 project is continuing; currently we're working on a Laserdisc copying system to backup the AIV discs properly (an FPGA based system which samples directly from the RF of the laserdisc player - allowing a copy to be made of all the information on the disc without going through 30 year...