Hi, according to the emanual, "After the DYNAMIXEL receives an Instruction Packet, it delays transmitting the Status Packet for Return Delay Time(9). For instance, if the Return Delay Time(9) is set to ‘10’, the Status Packet will be returned after 20[μsec] when the Instruction Packet is received."
Can you let me know why would anybody want to delay transmitting the Status Packet please? If I want the shortest communication time among the dynamixels and the controller, should I set it to zero? Any disadvantage in doing that?
For servos that use half-duplex communications, you need time to make sure that the complete command has been sent, then switch over to 'receive', all before the servo starts to send its status packet so you don't miss anything.
The return delay time allows time for a slower controller to switch the data bus to RX mode, and when faster control frequency is required, it is recommended to set this value to 0.
If the controller cannot switch the data bus direction quickly enough, it could miss part of the status packet from DYNAMIXEL.
Thanks. So if I use U2D2 to control X series dynamixels, it is better to set the value to 0? Also, is it better to do it via the Dyanmixel SDK software or via Dynamixel Wizard? Is whatever parameter values I set in the SDK software only stays during the execution of the program or they will last until I reset again as if I were using the Dynamixel Wizard?
Since Return Delay Time parameter is stored in the EEPROM area of DYNAMIXEL, it doesn't have to do with the software you are using.
Once you set the value, it will last until modified or reset.
Thanks. There are two areas in the control table: EEPROM Area and RAM Area.
Am I correct that I can set the value of the parameters in both the EEPROM Area and the RAM Area via either the Dynamixel Wizard or within my C program that uses the SDK? Any pros and cons in setting the values in each area using either method?
Yes, you can access to both area with ANY software that provides correct communication packets.
However, EEPROM data can only be modified when DYNAMIXEL is TORQUE OFF status, while RAM area can be modified anytime.
There's no pros or cons on the software you are using, but you might want to keep the configuration in your own software so that you don't have to connect DYNAMIXEL Wizard 2.0 to configure the RAM area data.