1. Basic Operation

(a) ServoMax uses CAN communication and follows the Command/Response method. This means that response messages (RESP Msg) are not sent without a command message (CMD Msg), see below.

Figure 1. Command/Response Structure

(b) OP RESP Msg0 includes essential position and CBIT information, while OP RESP Msg1 contains optional information. Users can determine whether to receive Msg0 and Msg1 based on the status of their bus traffic (refer to the OP CMD Msg Frame for detailed configuration methods).

(c) The Memory Access function is provided for configuring control parameters required for operation. (For detailed instructions, refer to Ch. 7: Memory Access Function.) However, when using Memory Access, it is strongly recommended to turn the motor OFF for safety.

Sudden changes in parameter values may cause unexpected behavior depending on the current state of the servo. Therefore, before connecting the servo to any mating structure, users should thoroughly test the servo independently to understand the correlation between memory values and servo response.

(d) The table below lists the basic CAN IDs used by ServoMax.

Table 1. Default CAN ID

CAN ID (Default)	Description	User Change
0x100	OP(Operation) CMD Msg	Allowed
0x110	OP(Operation) RESP Msg0
0x120	OP(Operation) RESP Msg1
0x700	Memory Access CMD Msg
0x710	Memory Access RESP Msg
0x0	Factory Use Only	Not allowed
0x1FAA5AA5
0x0F57F010	Bootloader
0x1357F012
0x1357F00A

Figure 2. Bootloader Information

For the Bootloader Information CAN Msg, it is designed for standard ServoMax maintenance and is broadcast once at every power cycle.

Figure 3. CAN ID Distribution (based on Default ID)

The Factory ID is reserved for servo operation, monitoring, and maintenance within SME(ServoMax Engine), ControMax’s servo management software.

[Caution] Use of the Factory ID is prohibited.

(e) The convention for the rotational direction of the output shaft is shown in Table 2, as viewed from the front of the output shaft. Additionally, the directional sign can be reversed according to the CW_CCW_REVERSE_FLAG setting (refer to section 8.1).

Table 2. Direction Convention (Viewed from the Output Shaft)

Default, standard	Reverse

(f) [Caution] Changing the output shaft’s rotation direction (CW/CCW Direction) (refer to the Memory Map settings) is only allowed when both the offset setting is 0 (less than 1 degree) and the current output shaft position is also 0. This restriction is made because changing the rotation direction while either the offset or the current position is not zero may cause a sudden and unexpected movement, which could result in damage to the connected user system.

Therefore, if either of these values is not zero, the rotating direction change is strictly disabled. This safety measure reflects the analysis of various use cases and customer feedback.

(g) The Servo does not provide an internal mechanical stop.

[Caution] If the user system applies significant external aiding torque that may cause overshoot beyond the ±180° range, a mechanical stop must be implemented in the user system.

(h) [Caution] Before applying the OP CMD Msg, ensure that the output shaft position is not beyond the ±170°. If the OP CMD Msg is applied, the servo output shaft will rotate in the direction closest to the commanded position. If there is a possibility that the output shaft might move to ±170° or beyond while the power is off, a mechanical stop must be implemented in the user system.

(i) [Caution] When using the Memory Access function, be careful when specifying the memory target address. If an unintended address is specified, the internal, variable, values necessary for control may be corrupted, and the servo may malfunction.

(j) [Caution] The Memory Access(Read/Write) function is provided for configuring ServoMax and is intended to be used during the setup phase of the user system such as in laboratories or assembly lines. It is not originally designed for access during active position control while it’s still accessible.

Repeated read/write commands with a cycle faster than 100 ms may interfere with real-time current, velocity or position control of ServoMax. Therefore, do not attempt read/write commands at intervals faster than 100 ms.

(k) The zero position is not bound to a physical location of the output shaft teeth, therefore please use offset function to set such alignment as needed.

(l) When power is applied and no OP CMD Msg is received, the servo enters the default Motor ON state. Afterward, the motor state can be changed according to the MOTOR_ONOFF field in the OP CMD Msg

(m) PBIT results become available after 3 secs after power-up.