Beagle Bone Black 4D Systems 4th Gen LCD, could not request pin 40

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Mecha Lec

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Aug 27, 2019, 7:39:00 AM8/27/19
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I have a BBB Revision C, with 4DSystems LCD Cape. 

I am running 2net 4.1 Kernal ,http://www.2net.co.uk/android4beagle.html

The screen shows "Android" and then this fades out. 

Looking at serial I have this error: 

[    3.353484] pinctrl-single 44e10800.pinmux: pin 44e108a0.0 already requested by panel; cannot claim for 0-0070
[    3.363651] pinctrl-single 44e10800.pinmux: pin-40 (0-0070) status -22
[    3.370239] pinctrl-single 44e10800.pinmux: could not request pin 40 (44e108a0.0) from group nxp_hdmi_bonelt_pins  on device pinctrl-single

I think this might be why it doesn't continue with the Kernal but I could be wrong. 

Referring to all available forum posts regarding this LCD I have tried many different options in uEnv.txt to disable HDMI, disable universal cape and alike but nothing seems to work. 
I am not sure what command options are actually relevant to this particular build. 

I have also read that the boot int eh EMMC can also affect the overlays which are being loaded by the image in the SD card. I have ensured I have loaded one of the latest flasher images from official beagle bone site. 
Running just this flasher image, the screen does display correctly so I know it is not a hardware related issue. 

I have also double checked the overlay that is being used and all the pins are correct and match the schematic of the display. 

I am a newbie to Beable Bone Black and Linux so this is incredibly difficult and have spent weeks now trying to overcome this hurdle. 
So any help would be greatly appreciated. 

I have attached the serial outputs from the problamatic SD image and also for my base EMMC. 

Hoping someone could provide some info to push me in the right direction. 

BBB_SerialOuputEMMC.txt
BBB_SerialOutput.txt

John Baker

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Dec 14, 2019, 7:31:57 PM12/14/19
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I used a 4DSystems 4Dcapes for the BBB (https://4dsystems.com.au/products/primary-display-modules-capes-shields/4dcape-70t) and added a real-ttime clock board and an analog I-O board that I designed and had fabbed at OSH Park. I used  Debian Linux OS and programmed it in Python along with using Matplotlib and Tkinter. It was a little tricky as there are conflicts with the pins. You should check the pinouts in the schematics for conflicts and also check for help from 4DSystems.
Goodluck. 
John
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