Kflop Wiring for Leadshine Close loop step servo CSM22430

[AmitKumar171]

Dear Tom,

I want to interface a new hardware with KFLOP, that is leadshine close loop step servo CSM22430 and Drive CS-D508,

Please guide me through the steps and it is required to set pulse width more than 2.5uS in above drive but klfop having only 2uS, how to change that too.

link is in the description.
waiting for your kind reply.

https://www.leadshineusa.com/productdet ... el=cs-d508

https://www.leadshineusa.com/productDet ... =CS-M22430

above are the links for the products that i am interfacing with.

[TomKerekes]

Hi Amit,

Please guide me through the steps and it is required to set pulse width more than 2.5uS in above drive but klfop having only 2uS, how to change that too.

To set maximum pulse size use one of the following:

FPGA(STEP_PULSE_LENGTH_ADD)=63; // set pulse size to 3.78us
FPGA(STEP_PULSE_LENGTH_ADD)=63 + 0x80; // set pulse size to 3.78us and invert pulse

This is described here in the manual.

Because that Drive supports CW/CCW pulse mode it would be best to use that instead of Step/Direction as it avoids any Direction setup timing requirements.

[AmitKumar171]

Hi Tom,

I want to wire the above motor with KANALOG board using four signal wires for each step servo motors.

Signal that i require are PUL+, PUL-, DIR+, DIR-

And i have these options in my leadshine step servo. i have doubts in doing wiring.

Where to wire PUL+, PUL-, DIR+, DIR- on KANALOG board or kflop board as quadrature signal ?

Which output channel to select in config/flash screen for these kind of motors. ?

waiting for kind reply.

[TomKerekes]

Hi Amit,

Kanalog doesn't have any Step/Direction outputs.

How many Step/Direction outputs do you need? Are you using KFLOP JP4 and JP6?

You would need to use 5V open collector outputs. Connect + to +5V. Connect - to KFLOP Step or Direction pins.

Step and Direction is described here.

[AmitKumar171]

Dear Tom,

1. As per the Driver manufacturer datasheet, Minimal direction setup should be 5uS, but in KFLOP don’t know the default value. So, Can we change the DIR setup time to 5uS in the KFLOP? How?
2. Kindly advice, what happens if we run with 4uS even though Driver DIR setup time specification was 5uS? is this wrong thinking?

3. As per the driver specification, supply Voltage for the PUL and DIR should be 4.5-5V for HIGH and 0-0.5V for LOW (mentioned on page 4 of the manual,PFA link). But We have measured the voltage (using Multimeter) on driver pin PUL+ with respect to PUL- is: 1.29V(No operation/maybe on low pulse), while motor running: 1.43V (1200RPM), 1.52V(2080RPM).
And Voltage on driver pin DIR+ with respect to DIR- is: 4.06(When No operation and Anticlockwise rotation), 1.3V (when the motor rotates in clockwise).

We are supplying a lower voltage than the required voltage for the driver PUL and DIR, right? Is there any issue? If I am wrong, kindly correct & advise.

https://www.leadshineusa.com/productdet ... el=cs-d508

[TomKerekes]

Hi Amit,

As per the Driver manufacturer datasheet, Minimal direction setup should be 5uS, but in KFLOP don’t know the default value. So, Can we change the DIR setup time to 5uS in the KFLOP? How?

From the link to the manual I sent:

KFLOP sets the Direction output 1.92us before generating a Step Pulse. With the maximum Step Pulse length of 3.78us the maximum Direction Setup time to the trailing edge of the Step Pulse is 5.7us.

Also from my previous post:

Because that Drive supports CW/CCW pulse mode it would be best to use that instead of Step/Direction as it avoids any Direction setup timing requirements.

2. Kindly advice, what happens if we run with 4uS even though Driver DIR setup time specification was 5uS? is this wrong thinking?

Insufficient Direction Setup Time can cause the Drive to make one microstep in the wrong direction after any change in direction. This will cause an intermittent shift in position of 2 microsteps. Again use CW/CCW to completely eliminate the issue.

As per the driver specification, supply Voltage for the PUL and DIR should be 4.5-5V for HIGH and 0-0.5V for LOW (mentioned on page 4 of the manual,PFA link). But We have measured the voltage (using Multimeter) on driver pin PUL+ with respect to PUL- is: 1.29V(No operation/maybe on low pulse), while motor running: 1.43V (1200RPM), 1.52V(2080RPM).
And Voltage on driver pin DIR+ with respect to DIR- is: 4.06(When No operation and Anticlockwise rotation), 1.3V (when the motor rotates in clockwise).

We are supplying a lower voltage than the required voltage for the driver PUL and DIR, right? Is there any issue? If I am wrong, kindly correct & advise.

You can not measure microsecond Step Pulses with a multimeter. You would need to use an oscilloscope. But they should be similar to what you measure on the Direction Signal.

KFLOP should drive with >4V when sinking low and < 1.4V when floating "open". This does not meet the Leadshine Specification. But usually works as most any opto LED will need 1.4V or more to turn on. The open collector outputs on JP4 and JP6 do not have 47 Ohm series resistors as JP7 does so should drive with > 4.5V

If you need higher/lower voltage levels you will need to add an external driver. A differential line driver such as this should work well.

[AmitKumar171]

Dear Tom,

Thanks for the information and appreciate your support.

1. I thought STEP pulse and Direction setup configurations are independent, we can configure both individually like Step Pulse 2.5uS with Direction setup 5uS. So my understanding is wrong?
2. If I want to change the Direction setup to 5.7uS, we should configure the step pulse to 3.78uS right?
3. So we don’t have an option for configuring the Direction setup without configuring the step pulse width right?

4. Kindly advice the difference between 32 and 32+0X80, because we do not understand “pulse the Step High / invert pulse”.could you Kindly provide the graph for both the cases in details including the voltage/pulse width/etc for better understanding.
FPGA(STEP_PULSE_LENGTH_ADD)=32; // set the pulse time to ~ 2μs
FPGA(STEP_PULSE_LENGTH_ADD)=32 + 0x80; // set the pulse time to ~ 2μs and pulse the Step High / invert pulse
5. Why <1.4V when KFLOP pin is floating open? Why not it 0V? Because of the 47 ohm resistor?

[TomKerekes]

Hi Amit,

1. I thought STEP pulse and Direction setup configurations are independent, we can configure both individually like Step Pulse 2.5uS with Direction setup 5uS. So my understanding is wrong?

KFLOP's Direction Setup time is fixed at 1.92us. If the Drive is configured to step on the end of the Step Pulse then the total Direction Setup Time will be 1.92us + Step Pulse Time.

2. If I want to change the Direction setup to 5.7uS, we should configure the step pulse to 3.78uS right?

Correct.

3. So we don’t have an option for configuring the Direction setup without configuring the step pulse width right?

Correct

4. Kindly advice the difference between 32 and 32+0X80, because we do not understand “pulse the Step High / invert pulse”.could you Kindly provide the graph for both the cases in details including the voltage/pulse width/etc for better understanding.
FPGA(STEP_PULSE_LENGTH_ADD)=32; // set the pulse time to ~ 2μs
FPGA(STEP_PULSE_LENGTH_ADD)=32 + 0x80; // set the pulse time to ~ 2μs and pulse the Step High / invert pulse

Here is FPGA(STEP_PULSE_LENGTH_ADD)=63; // set the pulse time to 3.78μs
(Driving a 1.5K pull up to 5V)

Here is FPGA(STEP_PULSE_LENGTH_ADD)=63+0x80; // set the pulse time to 3.78μs and inverted
(Driving a 1.5K pull up to 5V)

5. Why <1.4V when KFLOP pin is floating open? Why not it 0V? Because of the 47 ohm resistor?

No, because all KFLOP IO have protection diodes connected to the 3.3V Supply.

[AmitKumar171]

Dear Tom,

Thank you for the information.

“The pulse length may be adjusted from 1 to 63 of 16.67 MHz clocks. Which corresponds to 60ns to 3.78us. Using a long pulse length limits the maximum frequency that can be generated. For example, with the default pulse length of 2us the frequency should not exceed 1/(2 x 2us) = 250KHz.”

1. The name “Pulse length” is the same as Pulse Width (Pulse ON TIME) right?
2. Duty cycle will be constant as 50% or it a variable?
3. How the motor speed can be controlled? By controlling the Frequency or Duty cycle?
4. As per the example/calculation in the manual, 60nS to 3.78us corresponds to 8.33MHz (=1/2X60nS) to 132.27KHz (=1/2X3.78uS), right? But its mentioned 16.67Mhz. How it’s? kindly advise.
5. If we need Pulse Width=2.5uS, then DIR Setup=4.42uS and Pulse input frequency=200KHz right? And in the firmware it’s written as FPGA(STEP_PULSE_LENGTH_ADD)=42; right?
6. If I reduce the frequency, only machine speed will reduce or any efficiency will drop?

[TomKerekes]

Hi Amit,

1. The name “Pulse length” is the same as Pulse Width (Pulse ON TIME) right?

Yes

2. Duty cycle will be constant as 50% or it a variable?

Variable depending on Step Frequency (motor speed)

3. How the motor speed can be controlled? By controlling the Frequency or Duty cycle?

Step Frequency controls the speed. Each Step Pulse moves some amount of distance.

4. As per the example/calculation in the manual, 60nS to 3.78us corresponds to 8.33MHz (=1/2X60nS) to 132.27KHz (=1/2X3.78uS), right

That is basically correct. But KFLOP specifies a maximum Step Rate of 2.5MHz. Also the minimum Step Period (1/Frequency) does not necessarily need to be 2X the Step Pulse Width. It depends on cabling and Drivers.

But its mentioned 16.67Mhz. How it’s? kindly advise.

The FPGA uses a 16.67 MHz clock. Therefore all times are multiples of 60ns.

5. If we need Pulse Width=2.5uS, then DIR Setup=4.42uS and Pulse input frequency=200KHz right? And in the firmware it’s written as FPGA(STEP_PULSE_LENGTH_ADD)=42; right?

Correct. But I told you many times to use CW/CCW instead of Step/Direction to avoid the Setup Time issue. Why don't you use it?

6. If I reduce the frequency, only machine speed will reduce or any efficiency will drop?

The Maximum Step Pulse Frequency x the Step Size determines the maximum motor speed. Nothing else should be affected.