[ Log In ]
[ Register ]

Question #: 14692

Question: How can I connect the Pokeys57CNC controller to a DRV8825 / A4988 expansion board?

Current Solution

The DRV8825 driver IC by TI (Texas Instruments) has two main connections called STEP and DIR. These are the two main connections that you need to use to connect to the Pokeys57CNC controller. You also need to connect the positive digital voltage pin (5V) from the Pokeys57CNC controller's motor connector to both the reset and sleep pins. The GND pin from the Pokeys57CNC motor connector is connected to the GND pin of the DRV8825 driver. The enable pin of the DRV88525 can remain unconnected.

There is a trimmer potentiometer on the DRV8825 that can increase or decrease the amperage setting for the motor. Depending on the DRV8825 board you purchased, there may be two pads to determine the amp setting while turning the trimmer (in the voltage setting on your multimeter).

The A1 and A2 is connected to one of the motor's coils and B1 and B2 is connected to the other motor's coil. There is a pin on the DRV8825 called VMOT that you will connect to the power supply (max 45VDC) and the GND pin next to the VMOT is the V- for the same power supply.

I hope this helps. If not, please add additional information on this thread.

Additional Information:
I followed (to the best of my ability) the instructions provided to my original question, but I did not receive successful results. When I followed the instructions and connected the ground pin from the Pokeys57CNC motor connector to the DRV8825 / A4988 expansion board, it stops the communication between the Pokeys57CNC board & the motors 1-3 that I had working previously. The DRV8825 / A4988 expansion board will be the fourth driver I am connecting to the Pokeys57CNC. The previous three drivers are PoStep-60's if that helps understand the issue.

Prior to hooking up the ground pin (I used pin 10 from the Pokeys57CNC motor connector) to the DRV8825 / A4988 expansion boards ground pin, I was able to see the power being applied via the red LED being illuminated on the DRV8825 board; after this new configuration the light is not turning on.

With the new recommended setup, I used a heat shrink solder piece to add the shunt for the connection to the sleep pin. The connection to the sleep pin is where I believe my issues are stemming from. I must be connecting it to the incorrect pin (within the 9 pin layout on the DRV8825 / A4988 expansion board). Do you have any reference to the 9 pin pinout on the A4988 expansion board? I double checked the pinout provided on the Texas Instruments page, but it only gives clarity to the pinouts on the DRV8825 board itself. After reviewing their documentation, I tried connecting the 5v (pin 9 from the Pokeys57CNC motor connection that's split to connect with the reset pin on the DRV8825 / A4988) wire directly to the terminal on the DRV8825 board and that didn't work either.

Any help or clarification you can provide would be greatly appreciated!


Other Possible Solutions to this Question

Get Help with:
This Product
Tech Support
This Product
Order Query
Tech Support
Not logged in. Log In Register
Track Order(s)
View Order(s)
I Want to Schecule a One-On-One Paid Tech Support Session
Book an Appointment Pertaining to a BuildYourCNC Product (Free)
Ask a Quesion Below (Free):
Book an Appointment Pertaining Other Equipment ($60/half hour)
Book an Immedite Appointment Pertaining Other Equipment ($120/half hour)
Ask a Quesion Below (Free):
Waiting for response... I may not answer immediately, but I was notified on my cellular phone so my response is forthcoming. If I don't respond immediately, you can always go to the [My Account] page to see all of our chats at any time.