DLPDLCR2000EVM: Blinking issue

Christophe Cloutier-Tremblay

Part Number: DLPDLCR2000EVM
Other Parts Discussed in Thread: DLPDLCR230NPEVM

Hi,

We bought several DLCDLCR2000EVM interfaced using a custom PCB to a raspberry pi W. There was no issue.( mid 2020)

The issue we are seeing are in the newly order DLP module. We are thinking it might be related to the different firmware on the device : https://software-dl.ti.com/dlp/pico-fw-selector/release_notes/FWSel_DLPC2607_DLPA1000_pm1_i2c0x36_v1p2p6.html

Here is the setup :

DLPDLCR2000 EVM -> custom PCB -> Raspberry PI W (Raspbian GNU/Linux 10 (buster) Lite CLI only)

Config.txt :

# Added to support DLP2000
hdmi_force_hotplug=1
dtoverlay=i2c-gpio,i2c_gpio_sda=23,i2c_gpio_scl=24,i2c_gpio_delay_us=2
dtoverlay=dpi18
overscan_left=0
overscan_right=0
overscan_top=0
overscan_bottom=0
framebuffer_width=640
framebuffer_height=360
enable_dpi_lcd=1
display_default_lcd=1
dpi_group=2
dpi_mode=87
dpi_output_format=458775
hdmi_timings=640 0 50 35 10 360 0 30 35 10 0 0 0 60 0 19200000 3

i2C command for initialization. Note that we are running without the LED attached to the EVM explaining the multiple register write :

raspi-gpio set 22 op
raspi-gpio set 22 dl
sleep 0.1
raspi-gpio set 22 dh
sleep 0.5

#Set 3 LEDs to 0 on DLP2607, start comm with DLPA1000 and propagate
i2cset -y 11 0x1b 0x12 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x13 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x14 0x00 0x00 0x00 0x00 i
 
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD3 i

#Turn off current directly on PAD1000
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x03 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD0 i
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD2 i
 
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x04 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD0 i
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD2 i
 
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x05 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD0 i
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD2 i
 
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x06 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD0 i
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD2 i
 
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x07 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD0 i
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD2 i
 
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x08 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD0 i
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x00 i
#Mask all off
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x0D i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD0 i
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0xDF i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD2 i
 
sleep 0.1

#Turn on DLPA
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD0 i
 
i2cset -y 11 0x1b 0x39 0x00 0x00 0x00 0x03 i
i2cset -y 11 0x1b 0x3A 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x38 0x00 0x00 0x00 0xD2 i
 
sleep 0.1


#UNPARK DMD
i2cset -y 11 0x1b 0x2d 0x00 0x00 0x00 0x00 i

#setup 
i2cset -y 11 0x1b 0x0b 0x00 0x00 0x00 0x00 i
i2cset -y 11 0x1b 0x0c 0x00 0x00 0x00 0x1b i
i2cset -y 11 0x1b 0x1E 0x00 0x00 0x00 0x01 i
i2cset -y 11 0x1b 0x0d 0x00 0x00 0x00 0x02 i

Here is the issue we are having. every VSYNC, there is a blink in the image. We are sending full 640x360 white pixel. We are also sending full 640x360 black Pixel. All data line have been probed direclty on DLPDLCR2000EVM and are exactly the same. Using a constant LED illumination on the DMD. you can see the photodetector glitching every VSYNC :

WHITE IMAGE, image turns black on VSYNC : Note that this is not visible with bare eye as the pulse is very short.

BLACK IMAGE, image turns white on VSYNC :

Again, we are not seeing this issue with our old board (more then 1 board tried).

There is now way we can find the older firmware (1.2.5) Online.

If you can identify another source for this issue, we would be happy to try. We have swapped multiple element, cable, DMD, Only the new DLPDLCR200 boards are displaying the issue.

Thanks,

Christophe

over 1 year ago

0 Maxine Cabrasawan over 1 year ago

TI__Expert 3905 points

Hello Christophe,

Welcome back to the E2E forum. Thank you for your business!

We are looking into your issue and will get back to you shortly.

Best,

Maxine

0 Maxine Cabrasawan over 1 year ago

TI__Expert 3905 points

Hello Christophe,

Were all of the boards you originally purchased bought in the middle of 2020? When did you purchase your second set of boards?

Did you find the firmware for each board from TI.com?

Maxine

0 Christophe Cloutier-Tremblay over 1 year ago in reply to Maxine Cabrasawan

Intellectual 265 points

Hi Maxine,

Thank you for looking into this issue.

Board working were bought from 2019 to mid 2021.

Board not working were bought from 2022 to 2023.

I did not find each firmware. Only 1.2.5 seems to be available online trough the search tool. (link provided above).

Thanks,

Christophe

0 Maxine Cabrasawan over 1 year ago in reply to Christophe Cloutier-Tremblay

TI__Expert 3905 points

Hello Christophe,

I'd like for you to swap in each of the older flex cables onto each of the newer boards, replacing the newer flex cable. Can you determine if your output improves or changes at all with any combination of these older cables and newer EVMs?

Best,

Maxine

0 Christophe Cloutier-Tremblay over 1 year ago in reply to Maxine Cabrasawan

Intellectual 265 points

Hi Maxine,

I've swapped the ribbon cable and the micromirror. The only way i get flicker free illumination is with the old board. The old board with new FPC and DMD doesn't flicker.

Thanks,

Christophe

0 Maxine Cabrasawan over 1 year ago in reply to Christophe Cloutier-Tremblay

TI__Expert 3905 points

Hi Christophe,

How many EVMs are you seeing this issue on? Is it on all of the new EVMs that were just purchased?

Additionally, can you share a video of the blinking/flickering that you're seeing?

Best,

Maxine

0 Christophe Cloutier-Tremblay over 1 year ago in reply to Maxine Cabrasawan

Intellectual 265 points

I am seeing this issue on 3/3 new EVM. I didn't see this issue on any of the old board (2/2).

I don't think a camera can capture the issue because the flicker time is about 200 us as you can see from the signal recorded by the photodetector above.

In our application, constant illumination is critical.

Again, thanks for your help.

Christophe

+1 Austin Snyder over 1 year ago in reply to Christophe Cloutier-Tremblay

TI__Genius 12785 points

Hello Christophe,

This on/off behavior that you are seeing here is a new process added to extend the functional lifetime of the DMD. We will not be able to support eliminating these pulses.

Regards,

Austin

0 Christophe Cloutier-Tremblay over 1 year ago in reply to Austin Snyder

Intellectual 265 points

Hi Austin,

Thank you for your response. Do all of Ti DMD have this new functionality ? Specifically : DLPDLCR230NPEVM.

Is this functionality firmware or hardware. i.e. Could we downgrade the firmware in order to remove theses pulses.

Thanks,

Christophe

0 Austin Snyder over 1 year ago in reply to Christophe Cloutier-Tremblay

TI__Genius 12785 points

Christophe,

All DMDs will have this feature. Unfortunately it will not be possible to have removed as it will be outside of our standards.

Regards,

Austin

DLP®︎ products

DLP products forum

DLPDLCR2000EVM: Blinking issue