I just finished the assembly of my Eleksmaker A3 laser engraver (2.5W). These are some notes for personal reference (I use Linux). Perhaps you find some useful information too.
The Laser is connected to pin Arduino pin D11 (both configured in
GRBL firmware and wired on Mana
SE board).
As others pointed out, to avoid an uncontrolled laser-flash on power-on, it is advised to add a pull-down resistor (1K to 2K):
The mana se board uses an Arduino Nano as MCU. So it's easy to update/change the firmware with e.g. the Arduino IDE.
I successfully used the GRBL v1.1f.20170701 version.
Flash firmware using avrdude, e.g.
avrdude -c arduino -b 57600 -P /dev/ttyUSB0 -p atmega328p -vv -U flash:w:grbl_v1.1f.20170801.hex
Download sources from https://github.com/gnea/grbl, install to
~/Arduino/libraries and open grblUploader example sketch in the Arduino IDE
afterwards. Compile & upload.
Start serial terminal connection with screen /dev/ttyUSB0 115200. Then
you have an interactive session with the GRBL firmware. Note that local echo
is off, i.e. you don't see what you enter. Commands typed in are in <<CMD>>
brackets. Example session:
$ screen /dev/ttyUSB0 115200
<<CTRL+X + ENTER>>
Grbl 1.1f ['$' for help]
<<$ + ENTER>>
[HLP:$$ $# $G $I $N $x=val $Nx=line $J=line $SLP $C $X $H ~ ! ? ctrl-x]
(Quit screen with CTRL+A+\)
According to http://wiki.eleksmaker.com/doku.php?id=eleksrom, the default settings are
- step mm 80 (
$100,$101,$102) - acceleration 200 (
$120,$121,$122) - Laser mode on (
$32)
Read settings with command $$ (see previous chapter).
<<$$ + ENTER>>
ok
$0=10
$1=25
$2=0
$3=0
$4=0
$5=0
$6=0
$10=1
$11=0.010
$12=0.002
$13=0
$20=0
$21=0
$22=0
$23=0
$24=25.000
$25=500.000
$26=250
$27=1.000
$30=255
$31=0
$32=1
$100=80.000
$101=80.000
$102=80.000
$110=1000.000
$111=1000.000
$112=10000.000
$120=200.000
$121=200.000
$122=200.000
$130=200.000
$131=200.000
$132=200.000
ok
Note: if not already done, put the protection glasses on now. And also make sure there are no nearbys smoke alarms ;)
To Turn laser on and off (make sure the weak light button is not pressed):
M3 ; constant laser power mode
$32=0 ; Laser mode off
S255 ; 255 = FULL POWER ;)
S0 ; OFF
M3 enables constant laser power
mode. $S32=0 turns
the laser mode off, so S255 has immedeate effect. Otherwise, when in laser
mode ($32=1), the laser will only be on during movements. Afterwards send a
S0 to turn the laser off again.
Use the weak light button and the focus wheel on the laser module to
focus the laser.
