No parallel video from Raspberry Pi to the DLP development kit

K Bonder

Part Number: DLPDLCR230NPEVM
Other Parts Discussed in Thread: DLPA2000, DLPC3436

Hello,

I'm trying to get video from the Raspberry Pi 4b+ to be projected with a DLPDLCR230NPEVM using the parallel interface. But, I can't get this to work and I think there are two problems.
1) A software package is missing thant enables the 'GPIO' command
2) A video source is missing for the DPI

I'm using a pretty stock set-up. A quite clean Raspbian install, a copy of the TI provided extra part for the config.txt file, and the standard 2" ribbon cable to connect the RPI to the DLP dev kit.
The sample software (like sample02_splash.py) can be run successfully. The only thing I have changed manually is the i2c bus number.

My question is basically the same as e2e.ti.com/.../dlpdlcr230npevm-usage-with-raspberry-pi-the-displayed-image-video-to-dlp-goes-back-to-default-splash-screen.
When the init_parallel_mode.py is run a message is displayed "sh: 1: gpio: not found". This is comes after the python command 'os.system("gpio drive0 {0}".format(gpio_drive_strength)'. I suspect the 'gpio' command cannot be loaded from the shell. This was also asked here e2e.ti.com/.../dlpdlcr230npevm-sh-1-gpio-not-found-error.
Do I not have some software installed that enables this 'gpio' command?

After the init_parallel_mode.py is run the projected returns to the last test-pattern that was displayed.
I suspect I have not set a video source for the DPI output. Can some one confirm or deny this?

Thanks in advance for any help.

Koen

over 2 years ago

0 John McKnight over 2 years ago

TI__Expert 5750 points

Hello User,

Thank you for your interest in DLP technology.

We will need some time to look over the information given and will get back to you next week.

Those links are not working on our end so please allow some time for us to see what threads you are referencing.

What version of the firmware are you using?

Regards,

John

0 K Bonder over 2 years ago in reply to John McKnight

Prodigy 20 points

Hi John,

Thanks for your response. The firmware I'm currently working with are:
FWSel_DLPC3436_DLPA2000_pm1_i2c0x36_v7p3p1.img
FWSel_DLPC3436_FPGA_Software_v1p1p0.bin

I'll give the links another try:

DLPDLCR230NPEVM: usage with Raspberry Pi: The displayed image/video to DLP goes back to default splash screen - DLP products forum - DLP®︎ products - TI E2E support forums

https://e2e.ti.com/support/dlp-products-group/dlp/f/dlp-products-forum/1083271/dlpdlcr230npevm-sh-1-gpio-not-found-error

0 K Bonder over 2 years ago in reply to K Bonder

Prodigy 20 points

I solved the first points of my problem. After I followed these steps http://wiringpi.com/wiringpi-updated-to-2-52-for-the-raspberry-pi-4b/ I was able to run the 'gpio' command to control the drive strength.

0 John McKnight over 2 years ago in reply to K Bonder

TI__Expert 5750 points

Hello User,

Can you read through this thread and see if it does anything for the behavior you are seeing?

https://e2e.ti.com/support/dlp-products-group/dlp/f/dlp-products-forum/1110016/dlpdlcr230npevm-dlpdlcr230npevm?tisearch=e2e-sitesearch&keymatch=DLPDLCR230NPEVM#

Thank you for your patience.

Regards,

John

+1 K Bonder over 2 years ago in reply to John McKnight

Prodigy 20 points

Hi John,

I copied the config.txt and tried it with several modifications but with no good result. I've also tried to check the DPI signals with an oscilloscope. After init_parallel_mode.py is run I do not see a pixel clock, HSYNC, VSYNC appearing on the GPIO pins.

There are two things that I suspect. Currently, I'm not using the Raspberry Pi with an SSH connection. Also, I have a 4K screen connected to it. Will these things be a problem?

Regards,

Koen

+1 K Bonder over 2 years ago in reply to K Bonder

Prodigy 20 points

I solved my problem. I disabled the display driver in the config.txt and used the SSH connection to control the Raspberry Pi. Then I ran the 'init_parallel_mode.py' and the desktop became visible.