Problems triggering a CCD camera from the Imaging Source

Hello Yin Lou,

#3. Are you not seeing the trigger pulse at all? Please set non-zero pulse width and verify if it helps. For example- Set Output Trigger Pulse Width to 10uSec.

Regards,

Sanjeev

Hello Sanjeev,

Thank you for your reply. I set the trigger pulse(10us,100us,1000us,...,1000000us), but it can't  work.

#1.This is the LightCrafter's settings. As follow:

#2.The camera's settings:

(1)frames rate: 60.00024

(2) Device trigger : value and polarity

(3) Exposure :

(4) Special:

#3. The trigger supply (PIN 1 of J7) is 3.3V. Is the voltage(3.3V) lower? I did a experiment-----supply a 5V power for camera, it can work, so I infer that  the trigger supply of the LightCrafter is lower. If my deduction is right, how to enhance the trigger supply?

Regards,

Lou Jin

Hello Lou Jin,

#1. OK.

#2. (3) Exposure picture - You may want to disable Auto functionality. By enabling this you end up reading the modified pixel data on the camera as it starts dynamically adjusting the gain of image.

#3. For this you need modification on the board. Refer to this thread http://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/850/p/260558/913724.aspx#913724 here it is discribed on how to get different voltages apart from 3.3V for external camera trigger.

Let me know if there any question I can help you with.

Regards,

Sanjeev

Hi Sanjeev,

I really  appreciate your help. And I refered to the thread above. But I understand a little.

# 1. How to remove R292 on the board? I do this as follow:

It is detached from the system board.

# 2. How to  install 0Ohm at R291. I use a cable to connect two pin on R291. See :

# 3. Above all , right ? If not, what's right?

# 4. I have a idea that I make a voltage  amplifier, and place it between the camera and J7. Is it available?

Regards,

Lou Jin

Hello Lou Jin,

#2 instead of connecting cable you could have used the same 0Ohm resistor you removed from R292.

#3. Your changes look proper to me.

Before going to option #4 I would suggest to test just with #1 and #2 changes.

Regards,

Sanjeev

Hi Sanjeev,

I still have some questions. Last night I did my experiment. I found no signal between Pin 1 and Pin 3. No signal! But Pin 2 and Pin 4 is 3.3 Voltage. I have no head.

DLP LightCrafter Control SoftWare's settings :

(if the settings is right)

#1. Before installing 0 ohm resistor at R295, the result of testing Pin 1 and Pin 3 is no signal. There is a 3.3V between Pin 2(Pin3) and Pin 4. And I do nothing for setting the DLP LightCrafter Control SoftWare or I don't open it, there is still a 3.3V between Pin 2(Pin3) and Pin 4. Why?

By the way, I can't  installed a 0 ohm resistor at R295. The system board is elaborate, and I'm  afraid to spoil the one.

#2. Refer to this thread http://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/850/p/263006/921546.aspx#921546, here is Wang zhen's questions. His and mine are the same. After installing 0 ohm resistor at R295,  the condition isn't changed.

#3. Would you use some pictures——how to install 0 ohm resistor at R295 and remove R292 on  the system board—— to explain my puzzled？

Regards,

Lou Jin

Hello Lou Jin,

#1. Refer to the schematics the Pin#2 of J7 is Trigger I/P and Pin#3 of J7 is Trigger O/P.

Both Trigger I/P and Trigger O/P signals are connected to bi-direction voltage translators U20 & U23 device TXS0101. By referring to the http://www.ti.com/lit/ds/symlink/txs0101.pdf device spec you will find that the  Port-B signal (to which trigger i/p or trigger o/p signal connected) has a internal 10K pull to VCCB which is 3.3V.

So, if you measure the voltage b/w Pin2 or Pin3 to Pin 4 of J7 connector you will find it is 3.3V.

Without R295 installed it is not possible to driver camera having opto-couple trigger input signal. You can take it to board shop to get the modification done.

#2. Please refer to  http://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/850/p/263006/921546.aspx#921546 I have answered there.

#3. At don't have any pictures to share with you. You can take it to a local PCB board shop and ask them to do the modification they would help.

Regards,

Sanjeev

Hello Sanjeev,

Recently, I'm busy doing something else. Last yesterday, I took it to a PCB board shop. And they used a cable instead of the 0 ohm resistor. They didn't install the cable at R295(two red points), but see figure(two red circles):

# 1. Is this logical?

# 2. I test its voltage, if other settings have done, and the result is 3.3V, 0V, -3.3V. They are volatile. I deduce that above the way  is right. Your outlook?

Regards,

Lou Jin

Hello Sanjeev,

Thank you very much for your help all the time. My problems have been done. Thank you again!

Second, I want to know something about DLP® LightCrafter™ 4500，but I have nothing on it. Could you provide me with its user‘s guide?

Regards,

Lou Jin

Hello Jin,

You are welcome.

The DLPLightCrafter 4500 user guide is available when we launch the kit. Please hold on until the announcement of the kit.

Regards,

Sanjeev

Sanjeev,

Sorry to reopen this old thread... since I need to do the same thing, I just want to clarify it a bit before I proceed.

From the discussions between you and Lou Jin, there are two ways to generate 5V trigger output:

1) Putting jumpers between R291 and R295; or

2) Directly connecting J7 Vcc pin to Pin 6 of U23?

Could you please confirm?

BTW on my board, R291,R292 and R293 all seem to be open?

Thanks a lot for the clarification.