0.7 degree per step would be perfect (because now I have steps of around 5.5 degrees).

@pledgy
Maybe they are using exactly the one you mentioned (the machine always welcome me with "Grbl 0.9i ['$' for help]"
Actually, the newest grbl 1.1 has laser PWM, which (I believe) can be used for servo as well by changing the frequency.
For the source code, they might consider releasing it as required by the GPL license of the grbl that it's based on.

Hi!

It looks like the PWM resolution is low.
So, sending S0 is equivalent to S1, S2, S3, S4 and S5. Only S6 makes servo move a little, but the next movement will be only at S11 (S6 is the same as S7, S8, S9, S10). And so on.

The other problem, S90 is the highest position you can send to the servo (everything higher than 90 is equivalent to S90).

It means, there are only around 16 or 17 positions that the servo can theoretically take, which is absolutely not enough for me, because I've attached a pencil in a different way (see the picture).

Any chance to improve the resolution?

@EleksMaker-Z

I've put a 20 kg torque servo... around 3A peak current. So better if I make a separate supply + driving mosfet.

99% used rom of 32KB is a pity, though, sounds familiar. I guess, I'll try sending information through PWM.

Hi!

I'm thinking of all kinds of modifications. So, question 1: if I put a custom servo instead of the provided one, how much current can I draw from the Servo port?

Question 2: I'd like to request a firmware that would support using the free pins of the Atmega. For example, send 0's and 1's to few pins or use them as Serial/I2C port? The reason why is because I would like to try:
using few servos;
modify servos and use torque feedback;
etc.

Thank you so much!

Thanks @MuuSer and @Zax for your pictures! My new servo is working perfectly with light loads. For heavier things I've already got the JX 6221MG (bigger size) and still waiting for 5kg micro size servo....

So, the question is, how much power can I draw from the Servo port? I've tried connecting my 6221MG, it's working well, but in the beginning of the movement the blue LED goes a little dimmer, so I'm a slightly afraid to experiment with this servo yet.

@MuuSer can you please take a photo showing the location of the servo hand at S0 (fully up) position? To help me set mine properly.

My servo got burnt on the very first day, I got a replacement on the local market.
As soon as I connected the machine to the computer and powered it on for the very first time, the servo got jammed, there was the cracking sound. I thought, I have to do something in software, so I was trying to find the right button, and after a minute I felt a smell of burned electronics. Servo was really hot.

For the replacement I've got the same size servo with metal gears instead of plastic (I don't know weather it's really better for this purpose or not), just picked whatever they had on the market.

Looks like, there are 4 transistors in a bridge circuit, one of which got burnt (see picture):

Ok, seems to be good now.

The problem was that the white moving platform was scratching along the black profile below because of the screws because there were the blue shims on the bottom. I've removed the blue shims, so the screws now protrude less, and everything seems fine.

Sorry, too bad there is no manual on that.

I'm trying to adjust right now. So now it's turned off and moving it myself. It seems like, Y axis is smooth, but moving in X-axis is more difficult and not so smooth. What could be the reason?