Arduino TTL blanking problem....

Im looking for some expert advice please..

Im building a laser harp using a Nano, scanner(galvo), 12bit DAC and a DPSS 200mW laser with TTL modulation...

The problem i am having is getting the laser to blank, i use a GND and a PWM pin for the TTL cable from the laser driver, no matter what i try i still get a line going through the animation..

If i wire the TTL and run the blink sketch on the Nano the laser will go on and off so i dont understand why it wont using the DAC..

Any help will be very grateful... Many thanks.. Clive :)

so i dont understand why it wont using the DAC..

Nor do I, without seeing your code.

cliveharper: There is nothing wrong code wise..

OK, so it's not a programming question then? I'll move this to Project Guidance.

cliveharper: Nope the schematics are private... Brought and paid for.. Just need advice on how to get the TTL modulation to work, harp builders will know what i mean... :P

Then you will be singularly unlikely to gain assistance here.

Clearly, you need to contact the vendor of those said schematics.

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