Is there a current limiting adjustment? If not how do I set the maximum current limit
JaneYu 2016-09-16 10:31:59 8 Views40 Replies Is there a current limiting adjustment? If not how do I set the maximum current limit
I want to use this driver with 2 motors that are rated at 1.4Amps. Is it possible to limit the 1.6A to 1.4A?
JaneYu I know where to connect the stepper motor. I need to know where to connect the step and dir signals. This is not for an Arduino application. I use a PLC that outputs step pulses and a dir command. But where are the P4 pins on the board?
JaneYu Does anyone know where P4 is on the shield board ? On the stepper motor board schematic P4 is called out as UNO I/O PIN. Where are those connectors?
JaneYu Just received the stepper motor shield board. I plan to use it to drive two stepper motors with step and dir signals from a PLC. The schematic shows step and dir inputs on P4 but I cannot find a connector marked P4. Where are the UNO I/O PINs located?
JaneYu Hi, I am unable to upload my sketch to my Arduino as long as the Stepper Motor Shield is plugged into the Arduino. I tried Mega 1280 R3 (from DFRobot) and also a Mega 2560 R3. I get avrdude: stk500v2_ReceiveMessage(): timeout as an error message. Tried to change the position of RUN/PROG switch, but it makes no difference. Do you have any idea what is wrong?
JaneYu Found out myself: When shield is plugged in, it occupies the Arduino Pins D0 and D1 (RX and TX) which are used for uploading from Arduino IDE. My solution was to 1) use other digital pins (D2 - ...) for my project 2) I bent the shield connectors for D0 and D1 to the outside, now they don't make contact with the Arduino when the shield is plugged in. Works.
Yes, you are right.
but this board has the switch program and run mode.
at run mode arduino pin 0,1 are used for Xbee, but at program mode external pin header is connected to Xbee.
So I can assign other arduino pin using jumper wire.
Anyway I've got the mail from DF robot engineer that they will fix inverter problem.
Instead of inverter IC(SN74LVC1G14DBVR ) they may use buffer IC.
Temporally, I removed that IC. and used voltage divider and communication was OK.
also run mode is good too
Thanks
JaneYu Hope you will do a great project with DF sensor.
Why does logic inverter(5pin IC) exist between Xbee's Rx and external Tx line.
I understand that 5.5v Tx from arduino must be converted 3.3v level for Xbee's Rx input.
But
SN74LVC1G14DBVR is logic inverter, that is it convert 5V to 0V and 0V to 3.3V.
Bluetooth Bee module's Rx communication is not possible because signal is inverted,
I must add logic inverter at the Arduino UNO's Tx line
another way adding voltage divider after remove that IC.
That's odd.
JaneYu Hi Chandru
Sorry to reply to you now
How much power do you use?
Whether the motor wires are connected correctly.
JaneYu Hey everyone, can I power the arduino from the same battery? Can I pass 5v down to it from the shield? Can't find this info anywhere.....
JaneYu The previous version which uses A4988 could change the current, there is a potentiometer on the motor driver. The new version uses DRV8825, which doesn't have the ability to change the current. Sorry for the lack of information, the new version has a resolution of 1/32 which is A4988 doesn't have. Please notice this.
JaneYu I want to controll 2 Steppers over the I2C connection of that shield connected to an other device like Arduino.
What do you mean with "I2C is expanded from the main board"?
JaneYu Hello,
I have a Nema 23 stepper with 1,8A (unipolar) and 1,9 mH phase inductance. Voltage is not in the datasheet. Will this shield be too underpowered or would it work? Asking because it will only run under very little load, turning by 90° once in a while.
Can you also recommend a power supply with the appropriate power and voltage?
JaneYu okay thanks! what about the voltage level 2.4V for the motor vs 8+V for the drive ?
JaneYu Ok. How much? What part number/process? I'm really surprised you don't just sell the modules separately. It's not like I can be the first person to ever blow one up...
JaneYu Sorry, we don't have a unique number for that part, please send an email to our sales: [email protected], we will help with the purchase processing.
In the loop, the interval of the pulse control the speed of the stepper
digitalWrite(M1steppin,LOW); // set the stepper at low level
delayMicroseconds(time1); // low level lasting time, means the interval of the pulse
digitalWrite(M1steppin,HIGH); // Rising step
delayMicroseconds(time2); // this is the width of the pulse high level
Here, time1 control the speed of the stepper, if time1 is smaller, the stepper is faster
JaneYu Thanks Robert! I think this "time1" is to control the width of the pulse. Maybe we are in different meaning with this "width". Anyway, what I am trying to do is to slow down the speed. The cart I made is required to run 4 hours in one cycle, but now it is only 7 minutes(time1=1us, time2=1ms). So I need to find ways to slow down the speed of the stepper. For time1 1us is the minimum, I tried to increase time2 which doesn't help too much. Doya have any advice?
Hello Robert. Do you have any result and advice? I seems cannot control speed with different PWM pulse width, esp. I want slow speed, but when the pulse width is narrowed down, I can't get slow enough speed.
JaneYu Thanks Robert. Yes, they are in two serial monitor. Actually, "Uno+Xbee" communicate with laptop through Arduino IDE serial monitor, while "XBee+XBee Explorer" communicate with laptop or desktop through X-CTU.
JaneYu Hi, Tao. I got your meaning. Using XBee to communicate is a good idea since it's easy and reliable.
Here, for your problem, because UNO only has one serial port(Rx & Tx), which are the digital pins 0 & 1. it's unlike Arduino with two serial ports (like Leonardo), that's why in your code, you set the software serial pins 2 & 3. However, because the design of the expansion shield, the RX/TX of XBee are connect to the TX/RX pins of UNO, which make the serial be occupied. So the solution is to make the serial between UNO and your laptop be the software serial which are pin 2 & 3.
Do you notice that on the expansion shield, there is a 7-pin socket called APC, it is used to connect some adaptors which also have TX/RX pins, these pins are used for UNO to communicate with your laptop (sorry, I might not explain very well), so if you use 2 jumper wires connect pin 2 to RXD and pin 3 to TXD, then your problem will be solved. because the software serial is set to be be the serial for UNO and the laptop, and the original serial is still used for communication of XBee and UNO. Then try it out, I think you can communicate in the console of XCTU and the IDE serial monitor.
You don't need to change your code.
P.S. if you use Leonardo, you don't need to do this wire connection.
