Search found 89 matches

by Budgie
Wed Sep 18, 2019 9:19 pm
Forum: hardware
Topic: Beeb 1MHz Bus FPGA Adaptor
Replies: 129
Views: 5444

Re: Beeb 1MHz Bus FPGA Adaptor

Elminster wrote:
Wed Sep 18, 2019 8:49 pm
Is this the SID in the ATOM FPGA, is there some thoughts it doesn't sound like the real one?


No purely curious on how accurate it is to the original. This is the first time I have ever played anything from the BeebSID
by Budgie
Wed Sep 18, 2019 7:52 pm
Forum: hardware
Topic: Beeb 1MHz Bus FPGA Adaptor
Replies: 129
Views: 5444

Re: Beeb 1MHz Bus FPGA Adaptor

I too have finally got round to building mine. Really useful board. Thank you Dave for creating this. Great for standalone use and for interfacing to the Beeb and Master. Thanks to the Wiki and Dave's comprehensive instructions all was very easy to build ! In terms of the SID in the ATOM is this exa...
by Budgie
Tue Apr 02, 2019 9:01 pm
Forum: hardware
Topic: 5.25" Floppy drive problems
Replies: 11
Views: 571

Re: 5.25" Floppy drive problems

Pretty sure I had this exact error with a 5/4 drive connected to a Beeb. It turned out to be dirty heads. It took a lot of hard cleaning with isopropyl. Hope that helps
by Budgie
Mon Mar 04, 2019 3:47 pm
Forum: hardware
Topic: FreeFi-232 v2
Replies: 137
Views: 6790

Re: FreeFi-232 v2

Thanks. PM Sent.
by Budgie
Sun Mar 03, 2019 10:35 pm
Forum: hardware
Topic: FreeFi-232 v2
Replies: 137
Views: 6790

Re: FreeFi-232 v2

Does anybody have any of the latest version bare boards for sale by any chance ?

Thanks

Andy
by Budgie
Thu Jan 24, 2019 4:45 pm
Forum: hardware
Topic: Retro Hardware in FPGA's
Replies: 13
Views: 925

Re: Retro Hardware in FPGA's

I’m using a few solutions 1. ULA board designed to fit the RC2014 solution. This board uses a Xilinx XC95144XL CPLD 2. The Nebula ULA board from Retroleum which I’ve reprogrammed with my version of the Zx spectrum ULA for learning purposes. Again a XC95144XL. This board replaces the ULA chip directl...
by Budgie
Tue Jan 22, 2019 12:45 pm
Forum: hardware
Topic: Retro Hardware in FPGA's
Replies: 13
Views: 925

Re: Retro Hardware in FPGA's

Really interesting feedback Myelin. It’s the type of conclusions I have been coming to but without any 2nd opinions so really helpful

Thanks again

Andy
by Budgie
Sun Jan 20, 2019 10:35 am
Forum: hardware
Topic: Retro Hardware in FPGA's
Replies: 13
Views: 925

Re: Retro Hardware in FPGA's

Thanks guys

Feedback greatly appreciated.
by Budgie
Sun Jan 20, 2019 10:01 am
Forum: hardware
Topic: Retro Hardware in FPGA's
Replies: 13
Views: 925

Re: Retro Hardware in FPGA's

Many thanks for the quick replies. So is there a reason when recreating certain retro hardware where you may need to use these techniques or can they always be worked around with other techniques. If so what ? As an example I've been working on the ZX Spectrum ULA design on Opencores https://opencor...
by Budgie
Sat Jan 19, 2019 8:11 pm
Forum: hardware
Topic: Retro Hardware in FPGA's
Replies: 13
Views: 925

Retro Hardware in FPGA's

Hi All, Hopefully its okay to post this question here. I've tried many other forums but never received a decisive answer. My question is this. When writing logic for FPGA's the best practice guides always say never:- 1. Use clock gating 2. Never use a normal combinatorial signal as a clock 3. Never ...
by Budgie
Sat Jul 21, 2018 8:46 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Okay so here's mine. Works flawlessly so far.

The first 4 images are from the BBC micro. The last 2 are from an issue 6 Electron. The TV resolution is 1920 x 1080 50Hz

Just realised I didn't set Elk=1 in cmdline but it seems to be fine ?
by Budgie
Thu Jul 19, 2018 12:31 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Missed mine. Stuck at the post office, will grab it tomorrow. Thanks Dave
by Budgie
Wed Jul 18, 2018 10:13 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Looking forward to the delivery. You are a one man industry Dave. Hardware, software and documentation to a very high standard. Great product to boot !!
by Budgie
Sat Jul 14, 2018 6:44 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Mine is also 1920x1080. I have a few though so can test a number of options possibly. I think they are all 1080p so may all be the same !
by Budgie
Thu Jul 12, 2018 4:10 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Very efficient. You can’t beat them Hakos, I have the older analogue control one.
by Budgie
Wed Jul 11, 2018 4:59 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

I’d be interested in one please Dave.

Thanks !!
by Budgie
Wed Jun 13, 2018 5:45 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

I think its great just to have the option. Without this your into expensive bulky alternatives !
by Budgie
Wed Jun 06, 2018 9:24 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

This is awesome Dave. Thanks for finally bringing this to life !!
by Budgie
Tue May 29, 2018 5:23 pm
Forum: hardware
Topic: Acorn Master and Electron cartridge breakout
Replies: 45
Views: 2547

Re: Acorn Master and Electron cartridge breakout

I would also like a set please

Thanks

Andy
by Budgie
Sat May 12, 2018 11:36 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

See below the test pattern (bottom only) after switch on and then after a calibration (i.e. pushing the button). Not sure why it doesn't calibrate on switch on ? Is the second image after calibration? If so, then something is wrong as it has picked the worst possible sampling point! Can you grab th...
by Budgie
Fri May 11, 2018 4:42 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Yes I've monitored the log and it does everything you say. What resistor size did you use in the clock wire ? and was this the 96Mhz clock of the SP_CLK ? The test pattern (especially the bottom half of the screen) definitely makes a difference when testing. If you just look at text it can all look ...
by Budgie
Fri May 11, 2018 2:46 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Hi Budgie, Great that you have made some progress with this. I had quite a few problems with getting a prototype working reliably. I found the earth between the Pi and the CPLD board needs to be very good. I also needed to add a resistor into sp_clk line to prevent ringing causing unwanted clock tr...
by Budgie
Thu May 10, 2018 11:37 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Well I've programmed the CPLD and after some messing it works ! I've used a CPLD board I had which creates a Spectrum ULA for the RC2014 board. Just something I had which allowed me to use a XC95144XL CPLD. Well for anyone else who may be messing around with this I have found the following 1. If you...
by Budgie
Tue May 08, 2018 11:05 pm
Forum: for sale / freebies
Topic: BeebSCSI mini
Replies: 168
Views: 19318

Re: BeebSCSI mini

Hi,

I’ve just ordered one.

Thanks

Andy
by Budgie
Thu May 03, 2018 10:48 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Think I now have the pi code compiled and working. It comes up with INFO: RGB to HDMI booted INFO: Nominal clock = 384000000 Hz That seems OK - does it hang at that point? The next thing it does it to try to do some measurements of the VSYNC frequency, and I'm not sure what happens if there is no V...
by Budgie
Thu May 03, 2018 5:56 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Think I now have the pi code compiled and working.

It comes up with

INFO: RGB to HDMI booted
INFO: Nominal clock = 384000000 Hz


Hope thats correct. Now onto the CPLD. I'm away this weekend so maybe sometime next week...
by Budgie
Wed May 02, 2018 8:48 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

dp11 wrote:Under windows use the bash shell . Roughly follow the instructions here :https://github.com/hoglet67/PiTubeDirec ... pendencies
Thanks. Just looked there now after remembering PiTubeDirect was also based on a bare metal solution.

Will give this a go

Andy
by Budgie
Wed May 02, 2018 8:20 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Hi Dave

How do I compile the Pi source code. I’m running Windows. Do I need to download CMake and then play with the scripts. Just asking now in case I start installing all this and it’s not the correct process.

Thanks !

Andy
by Budgie
Thu Apr 26, 2018 9:55 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

I'll have a look at this tonight. From what I can see, it should be possible to simplify it a bit by removing the 3.3V regulator (seeing as the Pi will power the 3V3 rail) and moving the JTAG header out of the way of the signals that go to the Pi. I'll report back once I've had a go at it! So that ...
by Budgie
Mon Apr 23, 2018 6:47 pm
Forum: hardware
Topic: RGB to HDMI using a Pi Zero and a small CPLD
Replies: 787
Views: 39873

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

Andy, This project probably isn't ready for prime-time yet, but if you are interested in prototyping then everything is on github. What issue is your Electron? If it's an issue 6, then you don't need the 74LS08, and prototyping becomes a bit easier. Dave Thanks Dave. It's an issue 6. I'll let you k...