DLPDLCR2000EVM: with Raspberry Pi

Hi Philippe,

I've got a feedback from our customer.

""thank you for your response, I have ordered shorter 5CM wires and a second DLP LightCrafter Display 2000 EVM and power supply. As soon as they arrive I can test out the shorter wires to see if they improve the projection. I did not understand how to relax the pixel clock can you give me an outline of some instruction of how to do this? Unfortunately there are no MickMake PCBs available , I did try to order one a few months ago, I am on a waiting list but have had no response. I would also like to enquire if you think it is ok to run the LightCrafter Display 2000 EVM continuously it will be in an exhibition for 3months.
I understand in time the bulb may die but aside from that might it overheat or have any other issues. I have ordered a second one.

PS I am using this powersupply recommended by a colleague of yoursTE20A0503F01‎
AC/DC DESKTOP ADAPTER 5V 15W FROM DIGIKEY

Regards,
Cedrick

Cedrick,

If you are running the system for a long period of time I recommend you review the recommended operating conditions information in the DMD datasheet (https://www.ti.com/lit/ds/symlink/dlp2000.pdf). If your operating conditions are not within the specification, you run the risk of having the DMD fail at some point.

How hot do you expect the system to run?

Regards,

Philippe

Hi Philippe,

Good day.

I've just got a feedback from our customer. Please see below.

I now have a 2nd raspberry pi and DLP LightCrafter Display 2000 EVM set up with shorter wires and I am seeing much the exact same quivering image on the raspi screen projection. I will attach photos and video. I use the same code but had to change to i2c-11 rather than using the proposed I2c -3 to display the raspberry pi screen.
I ran the i2cdetect -l and changed the code to

sudo i2cset -y 11 0x1b 0x0c 0x00 0x00 0x00 0x13 i
sudo i2cset -y 11 0x1b 0x0b 0x00 0x00 0x00 0x00 i

instead of the proposed
sudo i2cset -y 3 0x1b 0x0c 0x00 0x00 0x00 0x13 i
sudo i2cset -y 3 0x1b 0x0b 0x00 0x00 0x00 0x00 i

Do I need to go back and edit anything in the config.txt to match this change to 11
The image is still quivering and has a split line going through it. Philipe has suggested in other answers > Reduce the pixel clock output from the Raspberry Pi (lower is easier for the RPi to drive) . Can you ask him for instructions on how to do this reduce the pixel clock ?

Philipe also suggests adjusting the GPIO drive strenght in the command line to a value betweem 0 to 7 Adjust the GPIO drive strength. Do "gpio drive 0 <X>" in command line where <X> is a value from 0 to 7.
Does he mean to change it to 6 first "gpio drive 0 <6>"

then "gpio drive 0 <5>"

Can he recommend a no. between 0 and 7 ?

I also now have a warning sign coming up on the screen that says low voltage. I contacted one of you colleagues to suggest the correct powersupply and this is the one I am using.

So Yes thanks I still need some help, the projector in the gallery is also now displaying the low voltage warning it is also using the AC-DC switching power supply which accepts 50-60 Hz 100-240 V AC inputs, and outputs a nominal 5-V DC at maximum 3-A output current. Which your colleague recommended. For this purpose we recommend the TE20A0503F01 Desktop Wall Adapter (or equivalent). Which I ordered from Digi Key www.digikey.com/.../5400184

Many thanks in advance for your help. I will recheck all my wiring but its is strange that it shows almost exactly the same split through the screen and quivering. I am hoping that if Philipe can give me instructions on how to reduce the pixel clock and adjusting the GPIO drive strenght in the command line it will help . Many thanks Fiona

I hope you could help us further with this. Looking forward to your advice.


Regards,

Cedrick

DLPDLCR2000EVM.rar

Hello Philippe,

Please see the response of our customer below:

I made progress in resolving the jitter issue and also the low voltage signal displaying on the pi, however there is now another issue that I would also like some help with. As I mentioned before I bought a second DLP LightCrafter Display 2000 EVM to resolve some issues as the first one was already installed at the gallery. I connected the second DLP LightCrafter Display 2000 EVM to the pi using shorter jumper wires. To completely stop the jitter in the projection I reduced the GPIO drive strength to 2mA using the command gpio drive 0 0 & & set it to auto configure after every boot up in the sudo nano /etc/rc.local . The low power signal was still displaying on the pi projection. I measures the voltage across 5v & GND on the rasp pi , it was dropping 4.85. I then measured the voltage across the 5V on the barrel pin on the DLP LightCrafter Display 2000 EVM & GND on the pi to be 5.3volts. We concluded the issue was the power jumpers wires.

I had been following the Frederick VandenBosch tutorial, perhaps his jumpers were shorter or thicker. He suggested "I’ve added P2_6 (5V) via GPIO pin 2 to power the EVM from the Pi or vice versa. A bridge is then required on the EVM from P2_6 to J3 using the M-F jumper wire." I made a direct connection with one jumper from GPIO pin 2 to the EVM J3. The low power issue is now resolved and the signal is no longer appearing on the pi screen.
I would like to have one of the PCB boards printed for future projects but for my needs now I see a problem the pi zero does not have a Line out/headphone audio. (If you want to use audio currently, you'll need to make use of Bluetooth audio.) I do not think Bluetooth audio will not work for me on this occasion as it will fall out of sync.

So to get back to the new issue, When I went to swap the original DLP LightCrafter Display 2000 EVM which had been running continuously for 3 weeks, I found that the projection image had deteriorated a lot. There were a lot of specs in the projection. Perhaps Philippe can give some idea as to why this is happening? Is it perhaps because the projector is overheating because it is running continuously? Phillipe previously asked "How hot do you expect the system to run?" Is there a way to measure how hot the system is running? Will the fixes/changes we have made to the GPIO pin strength help and the low power voltage help with this issue. I am looking into adding a power off button the the raspberry pi to shut it down safely every evening this will reduce the time it needs to run www.makeuseof.com/.../ I will need to use a different GPIO pin which is not being used by the EVM . I will attach photos of the issue in the projection.

As you can see in the photos it is pretty bad. It would be great if Phillipe can give some idea as to why this is happening and suggest how to prevent it happening to the second EVM . Along with using a power button to safely turn off the pi every evening so we can then unplug the EMV , might it be possible to add a heatsink somehow to the EMV ?

I have also since found that the main issue with the Jitter in the projection was being caused by the long thin 5volt power jumper wire. When I made a direct connection with one jumper from GPIO pin 2 to the EVM J3 the jitter is resolved and there is no need to reduce the GPIO drive strength. As this is the case would Phillipe suggest leaving the gpio strenght higher than gpio drive 0 0 maybe at gpio drive 0 3.

Thanks again for your help it is very much appreciated. 

Regards,
Carlo

Hi Philippe,

Thanks for your reply , I have been following the tutorial (VandenBosch's) and as he recommended powering both the EVM and the Pi from the EVM "The EVM’s 5V/3A power supply is plenty to power both devices"I am using the recommended EVM power supply 5V/3A connected to the EMV barrel power jack. As I mentioned the low power signal is not longer coming on since I am using just "one jumper wire directly from GPIO pin 2 (5VOLTS) on the pi to J3 on the EVM.
However I can certainly swap to powering both the pi and the EVM separately using two power separate supplies. Before I do this can you please confirm if I need to remove the jumper wire that goes from the J3 on the EMV to GPO pin 2 (5volts) on the raspberry pi?

Yes the white dots are in the same place whether I am in video or EMV splash screen so I assume a DMD problem.Can you explain what you mean by the internal TPG mode and how to try it.How do I perform the TPG test?
As you can see in the attached photo I have not been powering the EVM from the raspberry pi. I have been powering the pi from the EVM recommended power supply . How do I check that "the DMD power rails (VDMD, VBIAS, VOFFSET, VRST) are all coming up and are stable on the EVM side"

It is possible that the EVM power supply was unplugged while the video looper was running on the raspberry pi. Is this a problem?

Do you think the problem might be that the EVM is running continuously for a long period if time , 3 weeks?
Thank you so much for checking this for us.


Regards,
Cedrick

Hi Philippe,

Good day. Here's what our customer told us.

I have been using a stable 5V-3A supply on the EVM side all along, the model was recommended by a colleague of yours before I got started on the project it is the TE20A0503F01‎AC/DC DESKTOP ADAPTER 5V 15W FROM DIGIKEY

I no longer have any low power issue. I found the reason for the low power issue was that I had been following in Frederick Vanden Bosch tutorial, in which he suggested adding P2_6 (5V) via GPIO pin 2 to power the Pi from the EMV. and A bridge then required on the EVM from P2_6 to J3 using the M-F jumper wire." Rather than using 2 connection jumper wires I made a direct connection with one jumper from EVM J3 to GPIO PIN 2 on the pi. This resolved the low power issue, it also resolved the quiver issue.

Perhaps it is better to unplug the plug on the 5V-3A supply on the EVM, rather than unplugging the jack from the barrel pin from the DLPDLCR2000EVM?

I also came across another article which mentioned that "The DLPDLCR2000EVM optical engine can be driven to 30 lumens at maximum current settings, but will also run at high temperatures. It is recommended that the user add a heatsink to the system when running beyond typical operating conditions to maintain the same unit temperature.there was a heatsink "

For example a heat sink like this
https://coolcomponents.co.uk/products/heat-sink-kit-for-raspberry-pi-b?_pos=1&_sid=b550872ad&_ss=r

This was the review which mentions the heatsink
www.element14.com/.../dlp-pico-display-projector-evm-beaglebone-black-review


Additionally, The I2C commands which should be used to switch to TPG mode (along with all other DLPC2607 commands) are covered in the DLPC2607 Programmer's Guide: www.ti.com/.../dlpu013a.pdf You can find the layout/and schematic information for this EVM on the associated reference design page: www.ti.com/.../dlpu013a.pdf
You should use the above to find the DMD power rails and track their behavior.

I looked through these documents but cannot find The I2C commands which should be used to switch to TPG mode , or the DMD power rails and track their behavior. The document is very extensive and detailed. It would be great if he could point me to which page they are on on the document and how to use the commands.