Ax-12+ not responding
Ax-12+ not responding
by clusher
Thu May 05, 2011 3:38 pm
Hello everyone,
I've read all the forums I could find before posting here, but all the ".... not responding" posts aren't quite my problem. I have also posted this question in Robotis forum: http://www.robotis.com/xe/qna_en/52720
I have a Bioloid Humanoid that I want to control using a Python controller I wrote on my laptop. I use a USB2Dynamixel to connect the laptop to the bioloid bus. For powering purposes, I also have the CM5 connected to the bus, but with a blank firmware (it doesn't read or write neither on the bus or on the serial port).
Some months ago I noticed a problem: the servos would stop responding when the CM5 serial port wasn't connected to the laptop (you guys can't imagine how much time it took to get to this conclusion).
I checked all the usual things: firmwares were updated; I used both the batteries that came with CM5 and some LiPos; I tried using the RoboPlus software, namely the Dynamixel Wizard, and it detects the USB2Dynamixel but stops detecting the servos as soon as I disconnect the serial port of the CM5. I even used the full search to see if it could be a baudrate problem. The switch of the USB2DXL is set to TTL, all ID's of the servos are right.
I need to emphasize this: everything works if the serial port of the CM5 is connected to the laptop. It only fails when the CM5 is taken (or the serial port is disconnected).
Like I said on the Robotis Forum:
"I actually think the same as MikeG: a grounding issue. But I can't pinpoint the problem... it's not the CM5, because the servos are supposed to work well without it. It's not the batteries, since they work well powering the servos, with or without the CM5. The USB2DXL is "new", it only has a few months because I had a problem with the "old" one. And I don't think the problem could be with ALL the 18 servos..."
So... any comments/ideas?
NOTE: When I send move orders, the servos move. I just can't get a reply. And yes, the Status Return Level is set to 2.
I've read all the forums I could find before posting here, but all the ".... not responding" posts aren't quite my problem. I have also posted this question in Robotis forum: http://www.robotis.com/xe/qna_en/52720
I have a Bioloid Humanoid that I want to control using a Python controller I wrote on my laptop. I use a USB2Dynamixel to connect the laptop to the bioloid bus. For powering purposes, I also have the CM5 connected to the bus, but with a blank firmware (it doesn't read or write neither on the bus or on the serial port).
Some months ago I noticed a problem: the servos would stop responding when the CM5 serial port wasn't connected to the laptop (you guys can't imagine how much time it took to get to this conclusion).
I checked all the usual things: firmwares were updated; I used both the batteries that came with CM5 and some LiPos; I tried using the RoboPlus software, namely the Dynamixel Wizard, and it detects the USB2Dynamixel but stops detecting the servos as soon as I disconnect the serial port of the CM5. I even used the full search to see if it could be a baudrate problem. The switch of the USB2DXL is set to TTL, all ID's of the servos are right.
I need to emphasize this: everything works if the serial port of the CM5 is connected to the laptop. It only fails when the CM5 is taken (or the serial port is disconnected).
Like I said on the Robotis Forum:
"I actually think the same as MikeG: a grounding issue. But I can't pinpoint the problem... it's not the CM5, because the servos are supposed to work well without it. It's not the batteries, since they work well powering the servos, with or without the CM5. The USB2DXL is "new", it only has a few months because I had a problem with the "old" one. And I don't think the problem could be with ALL the 18 servos..."
So... any comments/ideas?
NOTE: When I send move orders, the servos move. I just can't get a reply. And yes, the Status Return Level is set to 2.
by i-Bot
Thu May 05, 2011 3:52 pm
You say you have no firmware in the CM5. ATMega ports by default float high, and this will probably enable the HC126 driver onto the Dynamixel bus. You may need some firmware to hold the enable low.
Are you using the CM5 just to provide power ? SMPS2Dynamixel may be low cost alternative.
Are you using the CM5 just to provide power ? SMPS2Dynamixel may be low cost alternative.
by clusher
Thu May 05, 2011 4:00 pm
I have the same problem even if the CM5 is not in the bus. I didn't explain very well the firmware part: I have a firmware, with all the initializations (inspired by one example I got on this forum a long time ago). It just doesn't read or write to the bus or serial port.
Right now, I have the USB2Dynamixel connected to a single servo, powered by the CM5 batteries, but without the CM5. I still can't get any kind of reply.
Right now, I have the USB2Dynamixel connected to a single servo, powered by the CM5 batteries, but without the CM5. I still can't get any kind of reply.
by Fritzoid
Thu May 05, 2011 4:30 pm
Hi clusher,
PORTE pins 2 and 3 control the dynamixel bus direction, you might want to look at how your firmware is configuring these two pins in particular.
Also, you should try powering your servo(s) without the CM-5. Do this by splicing a (9-volt) battery into the positive and negative leads on whatever cable you are using to connect the servo to the USB2Dynamixel. It won't provide the current to move the servo but it will allow you to connect without a controller.
PORTE pins 2 and 3 control the dynamixel bus direction, you might want to look at how your firmware is configuring these two pins in particular.
Also, you should try powering your servo(s) without the CM-5. Do this by splicing a (9-volt) battery into the positive and negative leads on whatever cable you are using to connect the servo to the USB2Dynamixel. It won't provide the current to move the servo but it will allow you to connect without a controller.
by clusher
Thu May 05, 2011 4:33 pm
No. I didn't even open this one yet.
Like I said, this is the second USB2DXL that I have. The first one had a similar problem, I wasn't able to read the replies, but the "CM5 serial port" part is new. Limor assisted me that time, and we also thought the problem would be with the FTDI chip (somehow I must have burned it or something ).
@Fritzoid - Some of the setups I tried were done without the cm5. Just like I said, I am doing it right now, and still no response.
Like I said, this is the second USB2DXL that I have. The first one had a similar problem, I wasn't able to read the replies, but the "CM5 serial port" part is new. Limor assisted me that time, and we also thought the problem would be with the FTDI chip (somehow I must have burned it or something ).
@Fritzoid - Some of the setups I tried were done without the cm5. Just like I said, I am doing it right now, and still no response.