Unable to find the right pin on Melzi 2.0 P802M for BLTouch
Good morning everyone, i know, i know: melzi is an old board and it doesnt have enough space for the repetier firmware, and i already banged my head in some walls BUT! I recently found out, that in my zonestar P802M (old model, one of the first, bought in 2015 and pratically never used because reasons...) there should be i spare pin to drive the BLTouch Servo (Actually a 3D Touch, which is the clone version) placed in the EXT connector.... i identified it and tried with every kind of number... from my research the A4 pin should be 28, but it changes based on what pinout i look at... i actually dont know which one is right and how to check if it works... a normal P0 S700 doesnt do anything on my probe.... can anyone indicate me the right pin number and which one to use ?
Repetier 1.0.4 (SD disabled, Arc disabled, servo enabled, autoleveling and probe enabled)
Based on this picture , i've chosen A4... but i dont know where to look to understand if that pin is used by anything and i have to select another one... I higly suspect that A4 is LED_PIN ... do i have to disable it ? how and where?
Any help would be greatly appreciated!
Repetier 1.0.4 (SD disabled, Arc disabled, servo enabled, autoleveling and probe enabled)
Based on this picture , i've chosen A4... but i dont know where to look to understand if that pin is used by anything and i have to select another one... I higly suspect that A4 is LED_PIN ... do i have to disable it ? how and where?
Any help would be greatly appreciated!
Comments
EDIT: I've also tried 1.0.x-dev just to be sure... still no movement... the bltouch seems unresponsive, using PIN 27/A4
The sensor do the "self test" when i power up the printer and stays retracted and with the red light on.
I've downloaded a simple arduino sketch on my arduino uno to test the functionality of the sensor and it works well (pin deployed correctly and touch works fine)
https://forum.arduino.cc/t/arduino-sketch-tests-a-3d-printer-tl-touch-auto-leveling-sensor/527949
is there anything a can do? As i'm disabling SD card support to squeeze the firmware in the melzi, is there any accessible pin or temporary pin i can use to test ?
https://www.electrodragon.com/w/images/a/a4/Atmega644-pinout.png
shows mapping arduino numbers . Pin 27 is PA3 according to this. You said A4 that is pin 28. On the other side if sketch worked it should be correct pin.
Deactivate timing is 1473 and activate is 647 also there is some variance allowed.
Have you configured servos correctly? Meaning num servos set to 1 and pin. I think that would be all to configure.
Also assuming pin 27 is correct make sure no other function uses same pin for something as well.
I'll attach my config asap , also ... Melzi is a 1284... Sanguino compatible so it should be this :
https://aws1.discourse-cdn.com/arduino/original/4X/0/7/1/0711dda9bdcbc5769fbd11bcdc27cc8b50b4a9de.jpeg
But it is labeled differently in the bltouch wiring tutorial ...
https://static.wixstatic.com/media/f5a1c8_ca35a8657c7a4322b6548e49bd78dd00~mv2.png/v1/fill/w_560,h_384,al_c,q_85,usm_0.66_1.00_0.01,enc_auto/MELZI_PNG.png
Right ?
I'll try again tonight with 27 and 28 also ... Just to be sure ...
Where do i have to look, apart from pins.h and Configuration.h to discover eventually free pins ?
I don't think it is a power problem. Main power comes from USB/Voltage converter and that is how more or less all are doing it.
yes I wrote that above :-) Good to hear it was just wrong timing and it now works.
It looks like I just need to set SERVO0_PIN to 27, but it makes no difference. Any ideas?
Kind regards
Steve,
if your chip is not listed here you can try replacing it by
#if 1
but processor must su[pport timer3 which is used for it.
Yes I saw this, but I probably didn't examine it properly Mine is "ATmega1284P or ATmega1284 (16MHz)". I'm not sure which.
It's an old Tronxy Melzi 2.0_V5.
Which means, I guess, if it were the ATmega1284, then it would fail. Where is the board defined in the code?
Thanks for your help,
Kind regards,
Steve.
Just adding that fixes it.
Thanks for pointing me in the right direction.