CM5908/5907 Plug-n-Play Bluetooth upgrade board

[James Crivellone]

Looking forward to ordering one

[djjerme]

I have a CM5907 I could try it in as well, let me know which you want me to beta with.


Sent from my iPhone using Tapatalk

[Todd Black 88]

Yes, I will be wanting to put it into a cm5907/5905 myself. That's what my m3 came stock with.

[bradnic]

- Sent Brad (bradnic) an early version of the board since he was going to The Vintage show. Thanks for the feedback and for reppin it at the show Brad!

my pleasure Jay. you've done something great here that the community needs to know about! thanks for the chance to experience the prototype. So pleased with the setup!

- I got the 5th print of the board back late last week (geez, isn't it done yet?) and this one is looking like a winner. I assembled one and was able to validate everything is working on both the 5908 and 5907. I worked out the auto-detection of the model on boot and kept one LED on the board to serve as a fault indicator that will light if neither model is detected (which could happen if you aligned the flex wrong on the 5907)

This is great news. What do you think of the possibility to detect the CLN alert and bypass it? Is it something you can do in the firmware or would there be wiring changes?

Also could you comment on the noise level on the last board with the RF shield in place? The old version I had is missing the shield of course, and with the engine off, in an enclosed space (garage) and very loud volume setting there was some high frequency noise. It was definitely not audible on the road at all, but the shield has basically eliminated it right? Can you confirm?

I have a total of 6 of these boards I can assemble - 4 for the current set of beta testers, 1 for me, which leaves one unaccounted for. I'd really like to find someone to install it in a 5907 and give it some real-world usage and testing - PM me if that's the radio you'll be installing in and want this last beta board.

Someone with a 5907 needs to jump on that! you will not regret your decision I promise you.

[stonea]

Man I'm getting excited about this now! I love the OEM and stealth look of it. I can't wait to get one!

Edit: Also signed up for the updates!

[jaysterling]

I've been heads down working on the project, so here's what I've got for updates.

- I launched a website: insideoutradios.com. It's more of a stub for the time being but it at least has an email list you can sign up for that I'll blast when they become available for sale. I'll be working on filling the site out more in the weeks to come.

- Sent Brad (bradnic) an early version of the board since he was going to The Vintage show. Thanks for the feedback and for reppin it at the show Brad!

- I got the 5th print of the board back late last week (geez, isn't it done yet?) and this one is looking like a winner. I assembled one and was able to validate everything is working on both the 5908 and 5907. I worked out the auto-detection of the model on boot and kept one LED on the board to serve as a fault indicator that will light if neither model is detected (which could happen if you aligned the flex wrong on the 5907)

Ran out of a few components to finish up the remaining boards, those should be here by the weekend. Then I have a few more RF shields to make up before I can get this first round out. I have a total of 6 of these boards I can assemble - 4 for the current set of beta testers, 1 for me, which leaves one unaccounted for. I'd really like to find someone to install it in a 5907 and give it some real-world usage and testing - PM me if that's the radio you'll be installing in and want this last beta board.

So this should be close to the final design now:


After too many hours of soldering - 1 complete and 3 almost complete units.

[bradnic]

One thing I neglected to mention that I was asked via PM..

The audio quality with Bluetooth is just amazing. Music sounds like a modern aftermarket head unit, and far superior to FM radio reception. Deeper bass, broader dynamic range and super clean sound.

Phone calls sound great too - as good as any of the 3 aftermarket head unit+amp combos I've used.

I do miss my trunk mounted tube subwoofer though. If and when we get a version of his kit with preouts I'm definitely switching to it

[Chrisbike]

I want this so bad, glad to see it's coming to fruition! I installed a factory CM5908 just for this.

[bradnic]

Jay's busy working new revs of the board. I was fortunate enough to have a prototype board in my E30 for my trip to Asheville / The Vintage.

Installation is a 4/10 in difficulty, with one connector being a bit of a pain to get to. It's definitely self-installable by just about anyone.

the install design, especially the way Jay reuses 3 screw on brackets from the tape mechanism on the replacement board.

Everything works as advertised!
- Push volume button to access radio functions, again to switch back to BT (AM/FM/WB, switchable with the BAND button)
- Phone calls from the OEM head unit
- Pause/Resume/Next Track/Previous Track
- Siri directly from the OEM head unit

I can't begin to tell you how wonderful the experience is. This is going to be a must do upgrade, right up there with a remote key fob retrofit.

Three quirks to get used to.. one may be manageable via the board design

1) If you get a random bluetooth refuse to re-connect situation happening, delete the pairing and re-pair. You may need to power cycle the radio as well. I had one pairing issue like this in 30+ hours of use, within the first 4 hours or so after install. It worked flawlessly after that.

2) There's a semi loud beep and a flashing "CLN" indicator on the head unit every 15 hours of tape use. This is by design to remind you to insert a head cleaning cassette! Shocked me a bit the first time it went off. Pulled out the radio manual and sure enough there it is documented, "CLEAN (Maintenance) Program".


3) You'll end up using the BT/tape mode most of the time once you upgrade. Unless you've done an antenna switch mod that means your power antenna will be up needlessly for long periods of time. I used a fog light switch in the empty slot of my hvac panel (those of you with the fader knob will need to come up with some other switch mount point).

How the pairing setup looks on an iPhone


Paired, BT mode, not playing


Paired, BT mode, playing


FM


Weather band (always fun). Manual power antenna button on upper left


I can't wait for a future version of this unit with added full pre-out support. In the interim you need to use the BMW premium sound amp if you want any sort of volume out of the car.

[Boggie1688]

Bump for pulse check

[earthwormjim]

Is that an E36 radio in the background I see? Future project hint?

[Appleseason]

How could i get one of those boards?

[Boggie1688]

All good Jay!! Plenty of other things to fiddle with while you iron out the details.

[jaysterling]

Project Update: I spoke with the guys doing the beta test offline but I did not get boards out at the start of May, I didn't get the board design out before going on vacation so that added time. I got the boards last week though and was shooting to send them out today.



Unfortunately, that is not happening either. I assembled the first board on Saturday and immediately had all kinds of problems. The bench supply was cutting power like there was a short, and after a bunch of painful back-tracing the problem it turned out to be the board print itself has a short from a power pad to the top ground plane. It's like an error in the printing itself though. If I probe the remaining bare boards, there are a handful of pads on the top on each that are shorted to ground. And it's not consistent; different pads are shorted on each board, but not one is all-good

So why such fail? Well I didn't pay attention to the isolate parameter on the top ground plane I added. This sets how much spacing it puts between the ground plane and other copper on the top. It defaults to a very small value, and I didn't notice to change it to something more reasonable. It did, however, pass the DFM check from the fab house, which is supposed to catch stuff like this. The min trace-space distance was reported as 4.99 mil on the report, and although it's in red, the test still passed. Anyway, there are tiny little shorts between pads and the plane, so unfortunately, oddly-shaped coasters is all these boards will ever be. I should have paid more attention to the report, and there's no need for the spacing to be so tight, but I would think if the fab house test passes, they're saying they can build it. So I'm working with them to see what they'll do about it.

Regardless, it's going to be another board rev before I'm ready for beta, which means another 2 weeks, so that sucks.

On a positive note, one of the new boards had its ground plane shorts strategically placed so I could at least test audio output through it, and was able to validate the changes I made. I still need the upright RF shield, but my home-made aluminum shield in here did the trick:



Still gotta find someone on allibaba who can supply something like it or could even press that piece custom. Thanks for the tip on that Jim.

So stay tuned, this will happen eventually! I've been working pretty long hours at my normal job lately so that hasn't been helping progress, but it'll get there.

Jay,

Do I need to be ordering a RPi2 in preparation for the beta board?

Nope, this doesn't use a RPi, that's the other version of this project you're thinking of from my other thread. That one's on hold for now.

[Boggie1688]

Jay,

Do I need to be ordering a RPi2 in preparation for the beta board?