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Raspberry Pi support

Open arslan437 opened this issue 3 years ago • 4 comments

Is there any way to use Raspberry Pi ?

arslan437 avatar Mar 03 '21 19:03 arslan437

Not right now, as it relies on the PRU of the Beaglebone Black.

There is a plan to integrate an FPGA at some point (and I think @hstarmans has something brewing), which would allow to use a simple Raspberry Pi and output to SPI.

I have that on my TODO list, but don't hold your breath as I also have a ton of other projects going on :)

hzeller avatar Mar 03 '21 19:03 hzeller

Thanks for the fast reply.

Can you share any document or link that explains how can we draw a dot? what pwm duty cycle or frequency ? or any other info that is help full

arslan437 avatar Mar 03 '21 19:03 arslan437

Drawing a dot is essentially switching on the laser at the exact time the mirror moved it to the right place; if you want to know the details, you have to read the code that does the synchronization. The highlevel design document explains some more context.

The laser is either on or off, so in order to get more exposure, you have to stay at one point and wait for multiple cycles sending multiple dots there. This is the 'exposure factorin the ldgraphy binary (option-x`): it slows down the forward movement of the board.

If you just want to use the device and draw a dot, it is as simple as creating a PNG file with a dot and giving it to ldgraphy - it does the rest.

hzeller avatar Mar 03 '21 19:03 hzeller

@arslan437 , here is an instruction video of my current setup https://youtu.be/Ri6DAneEzw4 The board can be found here https://github.com/hstarmans/firestarter/tree/master/pi_hat This all works and has been tested on Raspberry pi. The current code is in migen. I am upgrading it to nmigen and adding motion.

hstarmans avatar Mar 04 '21 12:03 hstarmans