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@harryberlin
could you make some comparison between pibus and bmwraspcontrol ?

i've tried your ibuscommunicator, but got an error in current kodi version 18. Is it supported ?
 

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Anyone run a Raspberry pi4 with Pete’s hat ? Just wondering if the power supply is up to providing 3 amps. Thinking of replacing my RP3 for a 4 to gain USB 3.0 for quicker processing of my 256gig usb drive and associated lossless music.
 

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Hallo guys, long time...

So far my project is still running and i thought i fixed all.

Everything works so far except the power management. In my test lab my power on/off event was working pretty well but not in the car.

I did not know that the IBUS goes back to battery level when communication is off. Thought it would fall down to 0V.

So i need some more info from pete.

How does the IBUS IC work. Pin 2 is controlled by pi. It sends 0V to shut it down which causes the IC to sleep and cut power off.

But how does it wake up when it is in sleep mode? Is it like all oem modules just waiting for a wake up message from the IBUS (IKE)?
 

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Already read the datasheet.

But i want to make the pcb failsafe if the pi stops working or is not present.

So i need to find a way to send 3.3V on Pin when IBUS is active and also 0V when IBUS is off.

In pibus the gpio is driven high when active and gets low when power off which sends IC to sleep until next wake up.

So any ideas how to make this possible when pi is not present?
 

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I will do some tests but maybe you understand me wrong.

My pcb is designed to work with and without pi, but the powermanagemant i use with timer to cut off 12V after 7 minutes from relais which powers the ibus ic and all other consumers does not work (as the ibusbis not going down to 0V as i thought).

So i decided to use the pin 8 frim the ic which delivers 12V which i will use to drive a n channel mosfet which will then give ground to the relais. Waking up is done by ibus itself, no matter if pi is present or not, but how to shut it down via pin 2 if there is no pi present.

I'd need to find a way to send the 0V on pin 2 if there is no pi present. Thats the problem right now.

And also i need to send 3.3V to pin2 when the ibus ic is woken zp, if i understand the datasheet right?
 

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I will do some tests but maybe you understand me wrong.

My pcb is designed to work with and without pi, but the powermanagemant i use with timer to cut off 12V after 7 minutes from relais which powers the ibus ic and all other consumers does not work (as the ibusbis not going down to 0V as i thought).

So i decided to use the pin 8 frim the ic which delivers 12V which i will use to drive a n channel mosfet which will then give ground to the relais. Waking up is done by ibus itself, no matter if pi is present or not, but how to shut it down via pin 2 if there is no pi present.

I'd need to find a way to send the 0V on pin 2 if there is no pi present. Thats the problem right now.

And also i need to send 3.3V to pin2 when the ibus ic is woken zp, if i understand the datasheet right?
Other options is to trigger Pi on power state via amp on / aerial amplifier power which comes from bm53/54 tuner ( white wire ) I do this to bring up a auxiliary distribution power block which remote ons amps , dsp , and powered USB hub for my raspberry pi.
Has things like USB bluray player and optical dac off it.
 

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you can use cheap arduino promini clone for power managment.

for pi wake up, only power +5V on.
check tx pin after some seconds. when it's high -> pi is on.
for shut down you need a communication to a pi process. send "shutdown" to pi. the process triggers shutdown. when tx pin gets low, turn off aftersomeseconds. if tx not comes low, wait 60s and turn hard off.
after this you can turn of the ibus chip.
if the 328p is powerd by ibus chip, it cuts off itself.
 

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The problem is not the pi.

I designed my own pcb which is kocated in tv module housing.

It sends hdmi out to a touchscreen in bordmonitor.

It switches between 3 sources (oem pic from nav, pic from pi if present, pic from rearcam if reverse gear selected).

It is designed to work with and without a pi. If a pi is present the shutdown is simple with petes pibus.

But how to manage shutdown if pi is not present. How to tell the used TI1501 ibus ic to go to sleep mode and cut off pin8.

Thought about consumer shutdown (16 minutes after closing doors this line goes to 0V) but that means to pull an extra wire.

It was better to use a logic which can interprete whether ibus is active or not.

Aerial power cable might also be an option, but if you turn of radio, will this go to 0V while still ignituon is on? If so, then all the rest won't work anymore.
 

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Same wire is power on for amp so selecting a different input doesn’t toggle on selection . Only issue present is that the car will send signal during starter motor engagement to drop power to the to much of the infotainment system such as white wire to ensure plenty of current available for starting. Not a problem for the raspberry but I put in a hold delay relay as my dsp would lock up sometimes.
 

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can't find your TI1501 datasheet. mine pibus has TJA1020.

Wenn der Pi fehlt oder nicht startet musst du dem ibus chip die signale ja irgendwie zur Verfügung stellen, deswegen der Hinweis auf z.b. den atmega.
So mache ich das ganze mit meiner Platine. rx und tx bytes werden an den Pi nur weitergereicht. damit läuft das ganze autark, auch ohne pi.

als simpelste Lösung kann mann ggf. was mit nen ne555 hinfrickeln.
 

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Aerial wire is no option, as it does not deliver 12v when car gets unlocked, just when ignition is turned on, thats too late.

Anybody knows a way or an IC to check if ibus is active?
 

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For the pin 2 ground issue could you connect to gpoi26 on the pi which is down by default but could be set to up with a startup script on the Pi. I’d forgotten, but I use GPIO 26 to power a audrino relay which powers a powered USB hub only when the Pi is on.

on the sleep and wake state I thought the th3122 and similar kbus chips new state and would change and advertise state accordingly ?
 

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Just to let you know, i fixed it.

And again the question was not how to with pi, but how to without pi.

For this problem i now use a diode connected to the ibus signal and make a timercircuit (se555) checking if there was a low (any message send on ibus).

If yes, the timer starts (60 seconds) and an output of 12V is given from this circuit which then activates a 3.3V regulator which then puts pin2 of the ibus ic to high which means awake mode.

If during the 60 seconds no message is send on ibus, the timer will stop feeding 12V to the 3.3V regulator which makes pin2 go low, which then means sleepmode and shutdown relais which is feed from pin8 of ibus ic.

Complicated but now it works for both operations.

If pi is present and pibus is working i have a 5 minutes delay from pi.

If pi is not present or not working for any reason then i have the 60 seconds delay which can be adjusted to more or less via variable resistor.
 
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