Engrave Photos with PWM Laser

RAyWB

Hi,
is there anyone experienced in engraving photos with PWM Laser?
just need some setups regarding grayscales as i´m not really satisfied with my results.

I use PLTB450 B 1.6W Blue Laser Diode with PWM capable driver controlled by 12 Bit PWM at 1KHz

Thanks

lucasss

I've try to engrave some photo but without a real good result..
See the photo on the end of the blog article...
http://www.e-tips.it/2017/03/20/incisore-laser/ Seems that for a gray-scale you have to drive the laser with a higher PWM frequency...
but in repetier-firmware, if you change the PWM frequency then it will decrease the resolution of the pwm, so you have less duty cycle value, so you cannot have a good result...

Edit.
I will add a question...
In the repetier, the PWM frequency is fixed?
If the frequency is made by the hardware peripherals and it is a fixed frequency, i will try to increase it with a micro-controller programmed for multiply the frequency...

RAyWB

there is a solution out of the box , see
https://github.com/repetier/Repetier-Firmware/tree/development/src/SampleEventSystems/Laser%20PWM%20and%20DAC I´ll post some pictures to my GitHub to show some pretty good results.
(may take a cuple of days)

lucasss

RAyWB wrote
there is a solution out of the box , see
https://github.com/repetier/Repetier-Firmware/tree/development/src/SampleEventSystems/Laser%20PWM%20and%20DAC I´ll post some pictures to my GitHub to show some pretty good results.
(may take a cuple of days)

Great! Fantastic work!
I've ordered two PCA9685 board and two solid state relay (i've got to machine).
I will tell you the result as soon i receive the parcel :)

Great work also with the fix:
Warmup for laser included (to avoid gaps in engraving)

<strike>I've downloaded your firmware and i will configure and try it ;)</strike>

Edit:
Ops, i've got the MEGA..

RAyWB

I have it running on a mega/ramps also.

use dev firmware and add the custom events , warmup and most other features are included in official repetier-firmware

lucasss

RAyWB wrote
I have it running on a mega/ramps also.

use dev firmware and add the custom events , warmup and most other features are included in official repetier-firmware

Hi, today I've finally received the PCA9685 board and I'm ready to try your code...

Can I ask you some confirmation?
I've copy the CustomEvents.h and CustomEventslmpl.h in the repetier firmware path, then compiled and load into Arduino MEGA...

Now I've just to connect the PCA9685 board to the i2c bus like described in the PDF file, and connect to it the laser? Right?

What kind of program have you used to create the G-Code in gray scale mode from a picture? Inkscape? with plugins?

Thanks a lots for your support,
Luca.

RAyWB

Yes, you copy the files to repetier firmware part.
in Configuration.h you have to enable Custom events by adding

#define CUSTOM_EVENTS

thats all.

there are multiple programs to generate the gcode .

i use pic engrave pro , there is a demo version available

lucasss

After adding #define CUSTOM_EVENTS there is some error in compiling:

exit status 1
'firstMove' is not a member of 'LaserDriver'

Edit. solved...just define CUSTOM_EVENTS upper than laser section...of course...

Problem N°2:
exit status 1
'newint' was not declared in this scope

on row:

#if defined(GAMMA_CORRECTION) && (GAMMA_CORRECTION==true)
newint =(com->S);
if (Gamma_on)
{
Outval=pow(newintens/LASER_PWM_MAX,GAMMA)*LASER_PWM_MAX; //Gamma function
LaserDriver::intensity = map((int)Outval,0,LASER_PWM_MAX,LASER_BASE_OFFSET,LASER_LIMIT);// scale gamma function and offset to max
Com::printFLN(PSTR("orig:"),(int)newintens);
}
else
{
Outval=newintens;
LaserDriver::intensity = map((int)Outval,0,LASER_PWM_MAX,LASER_BASE_OFFSET,LASER_LIMIT);// scale offset to max
Com::printFLN(PSTR("Gamma off LV:"),(int)newintens);
}

declaring it, it will compile the code, but i don't think that is a good solution...
Maybe i can declare it at the start of the file?

int newint = 0;

RAyWB

you have to use repetier 1.0 from dev branch !
do not modify the code

lucasss

I've configured and downloaded the 1.0dev firmware from:
https://www.repetier.com/firmware/dev/index.php Then i've add the customevents.h and customeventsimpl.h to firmware folder, and i've add the:
#define CUSTOM_EVENTS

after

#ifndef CONFIGURATION_H
#define CONFIGURATION_H

in configuration file...

The error still the same:
'newint' was not declared in this scope

RAyWB

in the github version of repetier the define is included at the end of configuration.h
(before last #endif)

when did you download the firmware files?

downloaded 3 min ago from https://github.com/repetier/Repetier-Firmware/tree/development compiles without error.

what arduino version do you use?

EDIT::

Typo, please change

newint =(com->S);

to

newintens =(com->S);

thanks for the hint!!!

do you use only the pca9685 or also the mcp23017 and mcp4725?

RAyWB

if you only use the PCA 9685 the settings in CustonEvents.h have to be :

#define FEATURE_I2C_MACROS false
#define FEATURE_EXT_PWM true

#define FEATURE_PWM_LASER true
#define FEATURE_ANALOG_LASER false
#define GAMMA_CORRECTION true

if not already done you also should set in configuration.h

#define LASER_PWM_MAX 4095

to get the 12bit resolution

lucasss

RAyWB wrote
EDIT::
Typo, please change

newint =(com->S);

to

newintens =(com->S);

thanks for the hint!!!

do you use only the pca9685 or also the mcp23017 and mcp4725?

Thanks to you for the support :)

Now i can compile without any problem, next week i will try to use the photo engraver with your code and will post the result :)
But before, i need to setup a mosfet for connect the PCA9685 to the laser...

Thanks

lucasss

Ok, I'm trying your code...
Seems working, but i cannot connect the laser at the moment (i'm using it with a LED) because i need to invert the signal...

from the code:

class PCAPWM
{
public:
PCAPWM(uint8_t address);
void Init(void);
void SetFREQ(float freq);
void SetPWM(uint8_t num, uint16_t on, uint16_t off);
void SetPIN(uint8_t num, uint16_t val, bool invert=false);

private:
uint8_t PCA_addr;
};

Theoretically if i change the invert=false to invert=true the output signal will be reversed?
I will power the laser trough a N-Mosfet, so i have to invert the output signal...

thanks

Edit.
Seems the bool invert=true has no effect on laser output status...
How can invert the output? When the arduino start-up, the output of the PCA should be LOW, and when the laser is powered on, the output should be HIGH

RAyWB

NOPE.

in configuration.h

Change

#define LASER_ON_HIGH 0

to

#define LASER_ON_HIGH 1

LeandroB

Hi, RAyWB

could you please make a video explaining how to install CustomEvents.h and CustomEventslmpl.h in the firmware, thank you.

RAyWB

just read Events.h its written there

LeandroB

When I add (#define CUSTOM_EVENTS)

in Configuration.h, the commands stop working on the repeat host, what did I do wrong?

RAyWB

may be you should tell me what additional hardware you have installed.

also download source and date

LeandroB

I am using a mega arduino 2560, ramps 1.4, with the Repetier-Firmware version 1.0.1dev