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[Ziq]

Hi, I got inspired by you guys and hooked up an mbed LPC1768 i had laying around to the CDC-connector in the trunk (removing the broken CDC was more work than i thought..).

I adapted Karlis code and the head unit thinks a cdc is connected.

I have a 9-5 Nav so it does not send anything audio related to the SID. Looking into your code i saw that you have a function send_display_request() but I cannot see that you use it anywhere? Is this message already sent by your headunit? Since it seems you get responces to this message but I don't...

[Karlis]

Hi Ziq,

Welcome to the club! :) The function you mentioned "send_display_request()" is our attempt to send over a custom text to SID, for example track metadata (artist/track) we could acquire from audio source over bluetooth.

CDC originally doesn't send this message to SID, but instead "reports" its status to IHU. As in "hey, I'm playing 30th second of 1st track of 2nd disc, and I have discs loaded in slots 1,2 and 5 of the magazine". It's then IHU that sends the information via 348 message to the SID. It is somehow tricky as some message priorities, lengths, etc. are involved that we haven't been able to crack yet.

The "send_display_request()" function "asks" for a permission to write it's own text on the SID. So if no one is currently writing anything to the SID (which almost never happens with IHU being turned on), we don't have a chance... If we do, however, send our text, it results in SID text flickering, showing 1/2 of custom text and 1/2 of IHU's text and all sorts of different weird things. :)

Long story short - the function is there, but we don't call it for now till we figure out how to bypass IHU <-> SID text control.

[Karlis]

Some guys on the web are using SPA <-> SID text control to send custom text to SID. That works, but I believe it could cause some problems for people with SAAB Park assist on their cars...

[Ziq]

Ah, that explains it. I barely ever have something on the second row. When I tried to activate the display I did however have a message to refill washer fluid. After activation park assist took over first row and the second half of the refill message was on the second row. After i removed the refill message and disengages reverse I got nothing.. Generally parking assist is only row 1, but every now and then it reports malfunction and I believe that is a two row message, so except for that the second row should be free.