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There are layout changes for v2 boards. Are there updated data sheets available? Specifically, is CN2 a reset connector? Is JP1 a logic supply select?

The datasheets are being updated still but I can answer any questions you have on the changes. The only major change is the Vcc selection for the s1,s2,s3 3 pin connections. You can connect the Vcc of each to 5v,2v or neither. In the older versions you could only connect to 5v or not. The 2v option is because the the Analog mode only support reading values from 0 to 2v on the new Rev C boards. This is a limitation of the new processor. But we decided the benefits(like 8million pulse per second decoding) outweighed this one disadvantage.

The encoder inputs are still laid out the same as are the S1,S2,S3 connections. The new rev boards also support E-Stop usign S3 when in packet or simple serial. Pulling S3 low will cause an e-stop. E-Stop on the new rev boards will immediately disconnect the motors. The motors may still take some time to stop moving due to inertia.

The error codes have been updated as well. I've posted them in other places but there they are again.

error led on solid, status1 or 2 blinking = over current error on the specified motor
error led blinking once with long pause = over temperature
error led blinking twice with long paue = main battery under voltage
error led blinking three times with long paue = logic battery over voltage
error led blinking four times with long paue = logic battery under voltage

all three leds lit solid = E-Stop

Main battery over voltage will cause the error LED to light until the over voltage passes. The controler will automatically recover from this state once the main battery voltage drops below the cutoff.

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Nathan Scherdin
Basic Micro - Robotic Technology Evolved

Thank you for quick answer. BTW, are you using STMicro STM32 microcontroller in Robo Claw?

No. We are using an xmega.

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Nathan Scherdin
Basic Micro - Robotic Technology Evolved

I had purchased the V1 RoboClaw boards a while back, and was wondering if the datasheets for the V2's were ready yet?

I am trying to decide if it's worth it to get the new v2 controllers, are there any other differences other than the Vcc selection for the s1,s2,s3 3 pin connections and the increased PPS from 150,000 to 8,000,000?

Thank You

If you aren't having any trouble with the V1 boards there isn't much reason to change out. Basically we switched to the new processors because we could combine the encoder functions and the control functions all into the one chip were we use to have a CPLD on board to handle reading the encoders.

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Nathan Scherdin
Basic Micro - Robotic Technology Evolved

Okay, thank you

Would also like to see the new docs on the v2 boards. Doing a power budget and was wondering if the typical power for the logic circuit on the 2x5a v2 is the same as the v1 board (90 ma)?

I'll check it when I get back to the office. I expect it will actually be a little lower since we dropped the CPLD.

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Nathan Scherdin
Basic Micro - Robotic Technology Evolved

I just got Rev. C of the RoboClaw 2x5A and I have a few questions before connecting it to my system.

1. What is the function of CN2 (asked earlier, but not answered)?

2. Since the ATxmega32A4AU is operating at 3.3V, has any testing been done with 3.3V serial communication signals? This is important when using a 3.3V processor such as the Arduino based “Mega Pro Mini - 3.3V” from Sparkfun.

3. Is there any special buffering that must be used when interfacing 5V serial communication signals?

4. What is the voltage level of the serial signal coming from S2? This is important because some 5V serial ports will not recognize a 3.3V signal.

5. Once the e-stop is pulled low, what happens to buffered commands? For instance, if 41/42 commands are being executed and 44/45 are in the buffer, will the 44/45 be cleared (etc.)?

6. While the e-stop is pulled low, will the RoboClaw respond to informational requests such as command 16/17?

1. I don't have one with me right now but if its the small screw terminal it's logic battery input. If its the 2x4 header its the encoder inputs/power. If its a not populated 2pin header then its for our using during production.

2. The Roboclaw has 3.3 zenor protection diodes and current limiting resistors so 5v signaling can be used. When used with 3.3v signalling the signal just goes straight through(no clipping by the zenors).

3. answered in 2. No special buffering required.

4. The serial output from S2 is 3.3v

5. When e-stop is triggered thats it. The unit shuts down. The motors will cost to a stop(ie they will see an open circuit). No new motion commands will be processed. Information commands still work IIRC. I'll have to double check on that. You can read the current error status but we are still updating the datasheet and that command may not be in the current datasheet(this assume the latest firmware as well, earlier firmwares wouldn't allow any commands on an e-stop). No other commands will function. You have to reset(power cycle) the roboclaw to clear the e-stop.

6. answered in 5.

Would someone email me a reminder to check the idle current draw and to confirm all the information(read back) commands still function when in e-stop.

nathan@basicmicro.com

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Nathan Scherdin
Basic Micro - Robotic Technology Evolved

Hi,
I having problem using packet serial..How calculate the QPPS,speed,acceleration and distance?

I have made some simple program using command 42- buffered motor M2 with speed and distance using PIC16F877a microcontroller with hitech C compiler..



The problem are:

Motor not stop when command to stop motor is send.Bythe way, the encoder resolution is 200ppr and is attached to the main shaft of the motor(attached after gearbox).
=========================================================================
Problem 1:
from my calculation the encoder resolution i should get is:

200ppr x 4 = 800ppr =====> correct me if i'm wrong
==========================================================================================
Problem 2:
to calculate the Qspeed, i used:
lets say i want the motor speed to 20rpm,so

20rpm x 800ppr = 16000 pulse / min ======> correct me if i'm wrong..is this 16000 value must be put to Qspeed??
==========================================================================================
Problem 3:
For acceleration, i dont know how to calculate so i just put 12,000 as said in the manual.
==========================================================================================
Problem 4:
My wheel diameter is 15cm and is attached directly to 200ppr encoder.

To find distance, i use this formula:

distance to go= (distance to go / wheel diameter) * 800

let say i want the motor rotates 1 rotation only..so,
circumference of wheel = Pi * wheel diameter
= 3.142* 15cm
= 47.13cm ~ 47cm
so, the value of distanceM2 should be is:

( 47cm / 47cm ) * 800 = 800 ========> is this value must be put in distanceM2? correct me if im wrong..
===============================================================================================

Problem 5:
Lastly, when o key in all the data, the motor does not move according to distance, speed and acceleration..PLease refer the attached source code above..

Finally, i really hope that somebody experts in this forum could lend me a hand:)) i really appreciate if can give any suggestions because almost 5 days i focused on this problem to solve.

By the way, if someone know how to set the PID, please kindly share it with us:))

Please move this post to a new thread. You are hijacking this thread which isn't really about what you are asking. Once you've started a new thread I'll be happy to answer all your questions one by one.

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Nathan Scherdin
Basic Micro - Robotic Technology Evolved