[pilatomic]

Hi Yann,

Regarding the logo, I do also have a mixed opinion about it.

Some background info :

My kit only replaces the LCD controller of the Beolink 5000. It has no bearing, and no info on the behavior of the remote, all it knows is what the Beolink 5000 CPU is trying to display, and tries to show that as faithfully as possible on the E-Paper display.

I can’t  freeze the display indefinitely when the remote goes to sleep, as now the display state (and user expectations) does not match the actual remote state.

I did that with the previous E-Paper for a limited duration in an attempt to make of for the time lost while the refreshing the E-Paper, but it messes with user interactions, especially in menus where keys behave differently.

I am removing that behavior with the new E-Paper, as it is not required anymore due to almost instant refresh, which means the display will now immediately show what the original display would show.

Also, E-Papers cannot always rely on fast refresh, and need a full refresh cycle from times to times. Doing it when the remote goes to sleep is the best option (as a few seconds delay at that time does not hamper user interaction).

So now the only “correct” option would be to blank the screen when the remote goes to sleep.

I actually wanted to always show a logo to match the selected source, but didn’t like the result.

So I ended up only showing the logo while the remote is sleeping, but I wasnt satisfied with how it is placed on the screen.

With the new firmware I made it smaller and I think it fits better on screen. (see here)

If you have a suggestion for another design for the standby screen, feel free to chime in, preferably with a clean picture, else being only a firmware guy and not at all an artist, I’ll probably mess it up.

Last thing, I am thinking about replacing the standby screen with a special “LOW BATTERY” screen, as the E-Paper starts to behave erratically (resets) before the Beolink itself suffers from low battery voltage, so showing an indication of what is going on seems like a good idea.

[pilatomic]

Hello,

It’s been quite some time already since I started this project, and despite its success in reviving many Beolink 5000, its biggest limitation has been the long refresh times of the E-Paper display.

Almost from the beginning, I have been testing several other E-Papers of similar dimensions, looking for one with a “Fast Refresh” feature.

None were satisfactory, until now. The manufacturer of the E-Paper I use in the kit just released a new E-Paper model that supports fast refresh.

I received a sample earlier this month, and have been working to write the firmware changes necessary to implement the fast refresh function.

I am glad to report that it works beautifully !

You can see it in action here : https://pila.fr/wordpress/wp-content/uploads/2024/09/beolink5000_Epaper_V2.mp4

I have ordered a few more to run additional tests, and I still have a few things to improve, but it’s already a huge improvement compared to the previous display.

And the best news : it seems it will be possible to upgrade Beolink 5000 already fitted with my kit, only requiring the replacement of the E-Paper (of course), one resistor on the kit PCB, and a firmware update.

I’ll write more infos in the coming weeks

[pilatomic]

Hi Madskp,

I’m a bit late to the show, but I can answer your question.

Datalink sources always drive the audio lines, and it’s up to the receiver to select which source to listen to.

Which means a simple “Y” cable can not be used to connect 2 sources, it would require an active device, that would select which of the sources audio is sent to the to Beosound.

Even then, despite the Datalink protocol being design to have a Beogram and a Beocord on the same bus (only from a data bus point of view, not the audio), I don’t think the Beosound has kept that capability in its firmware.

In short, that can’t be done without a (specially designed) active adapter.

[pilatomic]

Hi @kleb,

Thank you for your feedback !

• I have checked the documentation of the Bluetooth chipset I’m using, and it seems possible. I might look into that in the future.
• Hmm this one I haven’t seen, but I mostly use my Beotooths with an Android phone or a Linux PC. I’ll try to get my hands on a Window PC to check that !
• You’re right about that. In my mind, the Beotooth is meant to be used at a fixed volume level, with the volume controlled by the Beomaster. I’ll  try that, and see if I can make changes to the scale.

[pilatomic]

Glitch : I already tried to squeeze the pins together without taking the connector appart (using small pliers), it seemed to help temporarily, but not for long.

Thank you for the picture of the pin. I’ll look for potential replacement connector, but this type of speaker socket has been out of style for quite some time now, not sure if some PCB-solderable parts remains.

[pilatomic]

Hi Die_Bogener,
Thank you for the tip !

I forgot to mention that I already did a full restoration of that Beomaster a few years ago, which included replacing the relays, so I know the relay is good.
(btw if you do so, make sure you use Cadmium plated relays for the power supply relay, newer, Non-cadmium relays really don’t last long with the inrush current).

Also just moving a bit the speaker plug in the connector is usually enough to get it working back, so it really behaves like a connector fault.

[pilatomic]

Hey, Sorry for the long delay answering, since the forum update I don’t get emails anymore when replies are added to the thread.

On T.W.G said

<p>Very interesting device and good work!</p>
<p>Does it support other codes than AAC? For example aptx?</p>

<br>

The Beotooth uses the Microchip BM83 Bluetooth module, which only support AAC and SBC.
I ad a look at AptX in the beginning of that project, but it is a Qualcomm proprietary technology, only available on Qualcomm Bluetooth modules,
and Qualcomm doesn’t give their SDK to everybody except, so no luck there.
AAC should deliver a similar quality to AptX (except on some phones where the AAC codec seems flawed, but that’s an issue with the phone manufacturer).

On Madskp said

<p>A little curious question. Would it be possible to change the TAPE command with the CD command for the Beotooth 5500?</p>
<p>One usecase I could seen for this is a computer using one Beotooth as speaker connection, and the other beotooth could the be used for connecting a phone</p>
<p> </p>

<br>

That’s an interesting idea, I had not thought about that (as I still listen to CDs on a regular basis).
On the back of my mind, swapping the control messages should be fairly easy, the status messages are a bit different though, but nothing impossible.
I’ll have a look at that when I have some free time.
(It could be added as a selection command through the USB Serial interface, that is already used to customise the Bluetooth name of the Beotooth).
There would be only 2 options here : Beogram or Beocord emulation (AFAIK Beogram CD and Beogram uses the same command set).
On a system with CD / PHONO / TAPE / TP2, CD and TAPE share one datalink bus, and PHONO and TP2 share another bus.

[pilatomic]

The Beotooth is more targeted toward Datalink era B&O devices, those use a data bus through a DIN7 socket to plug into the Beomaster.

Your Beomaster is an earlier model, and doesn’t use the Datalink bus. The Beotooth would still work as an good audio source for it if fitted with a DIN5 connected instead of the DIN7.

I can’t seem to find the PM either on the new version of the forum, so if you’re interested nonetheless, just leave a comment on my website with your email address, and I’ll be in touch.

EDIT : I can’t seem to be able to post a link, is the forum really that broken ? 🙁

You’ll have to resort to lookup on a search engine “pila.fr Beotooth 5500”

For those who want the new FW version, maybe just do the same (ask as a comment on my website) until I find how to read / send PM.

[pilatomic]

Hello,

Already 2 months went by since my last update here, and I have another firmware update available :

V1.5 fixes an issue where the Beotooth would mistake a datalink command for a Play command, and start playing when it should not (typically triggered on some Beosystem by switching from CD to Radio).

As usual, contact me in PM to obtain the new FW and update instructions !

[pilatomic]

Bonjour,

Contact pris par message privé.

Cordialement

[pilatomic]

Bonjour Aladin,

J’ai conçu un récepteur Bluetooth adapté aux chaines Datalink : https://forum.beoworld.org/forums/topic/beotooth-5500-a-datalink-bluetooth-receiver/

Faites moi signe par message si vous êtes intéressé.

[pilatomic]

Hello,
Quick update for those who already own a Beotooth 5500.
Firmware V1.3 is now available, with the following changes :

• Fix playback not resumed when switching from Beogram to Beotooth (I was not processing that datalink command)
• Prevent transmitting AVRCP (Playback control) commands to Bluetooth player when player is not sending audio. This fixes an issue where I was listening music on my computer though the Beotooth, then switched to a headset. A few minutes later, The Beomaster would, rightfully, go to sleep, but that caused a “pause” AVRCP command to be emitted, pausing the playback. “Play” commands are still sent unconditionally, to be able to resume playback.

If you are interested to get that firmware update, contact me via private message.

In other news, I am still in contact with Microchip, diagnosing why the AVRCP Browsing feature is not working. Once that is solved, I should be able to support selecting a track by its track number directly.

[pilatomic]

B3OHACK3R wrote: Figuring that out would mean to download and decompile the firmware.

Just curious, how would you recover the firmware from such a device ? Is it still in a separate mask rom like the older B&O products ?

[pilatomic]

B3OHACK3R wrote:
How are you counting those 8 bits?
So in your capture from above – are you seeing two bytes each being 01010100?

Exactly ! Although I have the bit values inverted in my notes, since the bus is pulled to 5V through a resistor, and actively pulled low by the end devices, so I use ‘1’ when the bus level is 0V.

In its simplest form, all commands begin and end with a low bit (so they are effectively 6 bits left for the command), and are transmitted twice with an 8 bit pause in between. As the controlled devices became more complex, so did the protocol, and eventually it grew up into quite a bag of knots (French expression, but I think it should convey its meaning well enough).

The live status featured on the beosystem 5500 for example breaks both those rules, but still manages compatibility with older devices ! I’m quite impressed actually, I don’t know what the software tools were in 1986, but making that protocol work back then could not have been an easy task !

[pilatomic]

What I need to know is does this look correct, or do I need to do some settings in the Saleae application? Also if I export the data in binary format what is the best way to compare them to those datalink commands that are available in different online projects? I have found a HEX editor, but unsure what format I must show the data in to be compareable (BInary, HEX, Decimal ??) Thanks in advance

This look totally correct, here is a scope capture of out of the TAPE2 socket on my Beomaster 5500, from a few years ago.

I have successfully reverse engineered most of the DL-80 protocol, but my notes really need a good cleanup to be of use (It’s mostly a pile of different files, scope captures, logic analyzer traces, etc…)

I do believe the 2 pulses are either a compatibility mode for older devices (I think I read somewhere that some pre-datalink devices used double pulses to trigger play / pause), or a way to trigger a collision on the bus and get the end device to stop talking and listen.

What you have following that is definitely the “Beocord play” command, so I think you’re all set up.

B3OHACK3R : Don’t reason with the pulse length for the DL-80, it’s simply made of 8 bits packets with 3.125ms bit duration.

[pilatomic]

Hi pepps,

If you shorted live and neutral, there should have been no voltage applied to your Penta, so no damages. Did you check the continuity of the Penta power cord ? Is it possible that the cable was damaged during your modification ?

Regards,

[pilatomic]

Jeep 50 : Contacted you via PM

[pilatomic]

Hi,

I’m not too familiar with the DL’86, as my projects uses DL’80.

The easiest way to achieve control of your BM6500 might be to send the control codes over IR, that way you can just duplicate what your remote is sending.

[pilatomic]

Hello,

Right before the Christmas celebrations, as I have started shipping some Beotooth 5500, I have just put together an assembly / usage manual. You can find it there :

https://pila.fr/wordpress/wp-content/uploads/2023/12/Beotooth_Manual_V1.0.pdf

Wishing you all a merry Christmas from France !

[pilatomic]

Good evening,

Sorry for letting that many days go by without updates, I originally planned to write last week about my avancement,
but I caught the covid in the meantime, and while the novelty factor has dry out, the fever is still quite effective.

Anyway, I’m now back on my feet (mostly), so here are the news :

Following B3OHACK3R’s concerns about the usage of tantalum caps, I went looking for other regulators that would be stable with ceramic caps.
I found a new Texas Instrument part, the TLV761 : it is stable with output ceramic caps, has a lower Vdrop and a better PSRR than the LM1117 I originally selected,
which both means less noise when used on a noisy USB-C supply. Bonus points, it is pin compatible with the LM1117, and comes with a soft start function ! Perfect !
I’ll be using those with cermic caps from now on.

I did make some (rough) measurement of the PCM5102 DAC using my PC soundcard input to investigate the impact of changing the value of the output filter resistor.
Going from 470R to 100R produces a small (around -6dB) improvement of a bit of 50Hz present in the output. But that noise was already at a ridiculously low level (-90dB).
I reckon it lowers the output impedance of the system, making it a tiny bit better at ignoring the 50Hz ambiant noise ?
The improvement seems ever so small in my case, I don’t think I’ll implement it.

I also spent a bit of time working on the firmware. I does now identify itself as a USB CDC device when plugged to a computer,
which means you can connect to it with a terminal emulator (such a Putty), and get a command prompt.
Only 3 commands are supported now : querrying the firmware version, querrying the device bluetooth name, and setting the bluetooth name.
That means if you have multiple Beotooth, each one can be named to reflect the system it connects to.
More commands might be implemented in future firmware versions.

I did mill about a dozen enclosure, and the result is even better than the first I did, so now I have everything required to build the first few Beotooth.
I’ll be writing to those who sent me messages as soon as I am ready to ship theirs.

Wishing you all healthy holidays !

[Author]

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