CSRA64215 bluetooth module potentially bricked

[WLA]

Hi Folks,


first of all hello to everyone on the forum - a newbie here


I'm tinkering with various electronics. Recently I took a challenge of repairng a decent Bluetooth headset and decided to use one of CSR modules. I managed to go through the hassle of getting it to talk to the FT232RL and after getting it to link, I made backups as usually advised in such cases.
Then I started playing around with settings for the csra64215. It came with no DAC setting so I took care of that, but while tinkering with event/button settings, I changed events for power on and power off...and now I'm in a bit of trouble.
The thing does not turn on at all, PST does not see it, no LED activity, etc.
All I did was to set Power Off and Power On events to Logical input ID 1 (which is a MFB line / PIO18).
Any idea how to make it boot again?
If I could only make it to force-start, I'd load the backup, but since I get no power/comms, I'm stuck


Looking forward to all suggestions
Cheers
WL

[WLA]

Hi Folks

There is some good news! I think I managed to un-brick it.
Had an epiphany while trying to sleep   The trick that came to my mind was to block external eeprom by grounding the "hold" input of the on-board 25u8033e for the boot-up phase. This prevented loading the problematic event setting and the module booted "clean". Then I let go of the eeprom input, linked the programmer and set the things to previous state.

Ummmph... I was afraid this thing is a toast.
Now, do you happen to know a good setting guideline I could use to use an input for standby or power on/off function?
The charging circuit does not work yet either. Any ideas what needs to be set in the CSRA to make it work on 5V external power and charge the battery on VBAT line?

Cheers

[Buriedcode]

As far as I am aware, the CSRA64215 ROM uses the multifunction button (MFB) for powering up/down.  It is sometimes call the VREG_EN as it initially enables the onboard regulators.  This is the only way to power up/down the module, but I believe you can change the config to change the time taken to hold the button down to do so. (because each button can have multiple functions depending on how long it is held for).

I'm not sure what software you have, but this page appears to have the version I use:

https://www.diyaudio.com/forums/digital-source/323164-program-csra64215-rom-15-csra64xxx-v2-3.html