Raspberry Pi 4 Released - Don't Buy for Portsdown

Discussion about this major DATV Project. See also https://wiki.batc.org.uk/The_Portsdown_Transmitter
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radiogareth
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Raspberry Pi 4 Released - Don't Buy for Portsdown

Post by radiogareth » Mon Jun 24, 2019 7:33 am

And the new RPI4 is released....thoughts??
https://www.raspberrypi.org/blog/raspbe ... LNR5s5vDHM

Gareth

G8GKQ
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Raspberry Pi 4 Released - Don't Buy for Portsdown

Post by G8GKQ » Mon Jun 24, 2019 8:45 am

Many of you will have seen that the Raspberry Pi 4 has been released this morning https://www.raspberrypi.org/blog/raspbe ... w-from-35/.

Before you ask, I don't know:
  • Whether the Portsdown software will work on it
  • Whether it will be better for the Portsdown than the Raspberry Pi 3B
I had hoped that it might have a hardware H265 video encoder to enable H265 video transmissions, but it only seems to have an H265 decoder. There is also a a major change to the operating system, so I anticipate a few issues in migrating Portsdown to the Raspberry Pi 4 IF (and only if) we choose to do it.

The Raspberry 3B and 3B+ will continue to be supported by the Raspberry Pi foundation for many years to come, so there is no threat to the Portsdown system. Quote from the press release:

"Are you discontinuing earlier Raspberry Pi models? No. We have a lot of industrial customers who will want to stick with the existing products for the time being. We’ll keep building these models for as long as there’s demand. Raspberry Pi 1B+, 2B, 3B, and 3B+ will continue to sell for $25, $35, $35, and $35 respectively."

I have ordered a Raspberry Pi 4 to play with and will keep you updated.

Dave, G8GKQ

2W0ODS
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Re: Raspberry Pi 4 Released

Post by 2W0ODS » Mon Jun 24, 2019 8:49 am

Was just about to post about the Pi4 here, saw it was released this morning.

Very interesting, especially true gigabit ethernet (the previous ethernet was on the USB bus) and USB 3.0, should pair quite nicely with the Lime SDR.

I think I'll order one and have a play myself.

g8lce
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Re: Raspberry Pi 4 Released

Post by g8lce » Tue Jun 25, 2019 9:02 am

Hardware decoding has officially been dropped in favour of software decoding in the Pi 4 and, along with it, the need to buy licenses if you want to play the MPEG2 and VC-1 codecs.

May be a slight problem.....

https://www.wired.co.uk/article/raspber ... ce-release

G8GKQ
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Re: Raspberry Pi 4 Released

Post by G8GKQ » Tue Jun 25, 2019 9:16 am

Hi Martin

You have always needed a license for the hardware MPEG-2 decoder on the Raspberry Pi: https://wiki.batc.org.uk/Lean_DVB_receiver#Menu
For MPEG-2 encoding, we have always used software encoding.

My RPi 4 should be delivered today. Then we'll know.

Dave

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Re: Raspberry Pi 4 Released

Post by G8GKQ » Tue Jun 25, 2019 9:18 pm

Although my Raspberry Pi 4 did not arrive today, I did try building an SD Card with the new Buster operating system (that replaces Stretch) required for the Raspberry Pi 4.

There was a problem with the openVG graphics that I use to display the buttons on the touchscreen. Until I have time to resolve this, the Raspberry Pi 4 will not work with the Portsdown software.

I'm sure that I will be able to resolve the issue, but I do not see it as a priority at the moment.

Dave, G8GKQ

G4FRE
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Re: Raspberry Pi 4 Released

Post by G4FRE » Wed Jun 26, 2019 6:37 am

Mine also didnt arrive yesterday, instead I had an email from CPC saying it would be delayed a day while they sorted out their website order code and price of the RPI4!

Dave
G4FRE

gi7ugv
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Re: Raspberry Pi 4 Released

Post by gi7ugv » Wed Jul 03, 2019 10:53 pm

Really happy with the 4, the USB/Ethernet changes are great as had issues with the limitations in the past, it does run a lot hotter.

I've been using mine here a bit for video already with an RTMP server running on it as described in the streaming part of the forum and ffmpeg on the Pi taking the RTMP input (from iphone or obs) and sending the h264 to limesdr_dvb. Works reasonably well but I've some issues to figure out still. When you start messing about with the like of this you realise how great the Portsdown is for taking care of it all for you! :)

gi7ugv
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Re: Raspberry Pi 4 Released

Post by gi7ugv » Sat Jul 06, 2019 11:32 pm

After some use it’s looking like it would really benefit from a fan for cooling. Under heavy load the CPU quickly throttles significantly. A small heatsink helped a little but not enough for my use, will try a fan next.

There’s firmware being tested that might reduce temperatures too but it seems this Pi is going to need more thought with regard to heat than previous ones.

G8GKQ
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Re: Raspberry Pi 4 Released

Post by G8GKQ » Thu Jul 11, 2019 10:12 am

The Raspberry Pi 4 will not be supported by the Portsdown software in the forseeable future. The reason is that the RPi 4 does not support OpenVG, which is the graphics programming language used for all the touchscreen menus on the Portsdown. At a first guess, I would need to rewrite about 20,000 lines of code to make the system useable on the RPi 4.

The definitive statement is here: https://www.raspberrypi.org/forums/view ... 0#p1497474

Needless to say, I'm really disappointed, but at least the Raspberry Pi 3B+ will continue to be available for many years to come. System development will continue using the RPi3B and 3B+. I hope to release software that will allow your Portsdown to receive and display signals from a MiniTiouner in the next few months, and also transmit increased symbol rates (2MS?) from a LimeSDR.

I will also migrate the Portsdown software to Buster Lite (from Stretch Lite) when time allows.

So, for your next Portsdown transmitter/receiver, don't buy an RPi 4, buy an RPi 3B+ and a 7 inch screen (or a LimeNet Micro and a 7 inch screen).

Dave, G8GKQ

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