Grbl hal connection

[arlimbad222]

Hi @zeevy @terjeio

I am switching grbl to grbl hal is it possible to connect grbl hal with this app i am trying with bluetooth but it's not working but with ugs i can connect arduino due with grbl hal .

https://github.com/terjeio/grblHAL

[zeevy]

It should work with correct baud rate set. And statup string should be same grbl

[arlimbad222]

Hi @zeevy

Baud rate is set correctly but what should i set to startup string can you please explain i cant understand what is the meaning of startup string.

Thank you for quick response.

[terjeio]

See this wiki page for info.

Grbl for 8-bit Arduino controllers run on hardware that resets the processor on connect, this causes Grbl to send the startup message (or string) automatically. Many controllers that grblHAL runs on does not perform this reset, and often it is not possible to detect a connection either. For these a sender will wait forever for a response that will never come unless they query the controller to detect its presence.

Then there is the startup message itself, grblHAL has many new features and by default sends a sligthly different message than vanilla Grbl so that senders can adjust, some senders do not recognize this. This can be changed by setting a compatibility level before compiling.

[arlimbad222]

Hi @terjeio @zeevy

So as i understand i have to change compatibility level for this controller is that right???

[terjeio]

So as i understand i have to change compatibility level for this controller is that right???

It does not hurt to try. Glancing at issues for this sender it seems that it is possible to configure the message so that grblHAL is accepted, this may also do the trick. But compiling grblHAL with compatibility level > 0 might be a safer alternative.

[arlimbad222]

Hi @terjeio

Okay i will try different levels then get back here.

[arlimbad222]

Hi @zeevy @terjeio

I try almost every compatibility level but I fail Bluetooth connected but no communication between the app and grbl what should I try next I attach some photos here.

[terjeio]

Do you have a computer or an app you can use to check the Bluetooth connection with. Connect via a terminal window (such as puTTY for Windows) and send commands manually, $I for controller info - ? for real-time status. If these do not respond there is a problem somewhere.

One reason could be that the wrong serial port is configured in the controller or that the RX/TX pins are not wired correctly (not crossed). The pins you have connected are shared with the USB programming port, don't know if this could be an issue, perhaps try with #define SERIAL_DEVICE 2 and use those pins instead?

[arlimbad222]

Hi @zeevy @terjeio

I try with compatibility level 2 and USB connection for my Android device and it works perfectly but with bluetooth it creates problem i don't know why ????

[terjeio]

i don't know why ????

It could be as simple as having the USB cable plugged into the programming port as the pins you have connected the module to (RX/TX) are shared with this. Maybe it works with the USB cable unplugged and an external power supply connected to the barrel jack? Or by switching to serial device 2 which uses these pins:

#define SERIAL_RX PIO_PB21A_RXD2
#define SERIAL_TX PIO_PB20A_TXD2

[zeevy]

Hi @zeevy @terjeio

I try with compatibility level 2 and USB connection for my Android device and it works perfectly but with bluetooth it creates problem i don't know why ????

App is working with the usb connection?

[arlimbad222]

Hi @zeevy

Yes app works perfect with usb otg.

[zeevy]

Ok, then as @terjeio said problem might be in physical connection of Bluetooth module or in baud rate of the module.

1. Check the physical connection
2. Verify the baud rate of the module with Arduino IDE or with any other tools. (make sure Bluetooth baud rate and firmware baud rate both are same)

[arlimbad222]

Hi @zeevy @terjeio

I am trying to give external power to the board then connect via bluetooth but still not working

I have one spare Arduino mega2560 i try my bluetooth module with that and it's working properly now this is not bluetooth module issue.

And i cant find any baud rate setting in grbl hal any clue @terjeio how to set baud rate ?

[terjeio]

how to set baud rate ?

You have to edit grbl/serial.c - line 46.

I have checked with my Due and both USB and UART mode can be used at the same time(!) Pin 0 and 1 are connected to the USB <> RS232 chip so they work in parallell, I did not know that. Since USB is comms is working then could it be that your Due is somehow faulty? I have an original Arduino Due, yours is a clone? If you have a voltmeter then check that the voltage on pin 0 and 1 is 3.3V.