The MCx devices are highly configurable in terms of motor and system level parameters like acceleration time, current limit, fault response and retry time, fault (overcurrent/overvoltage/undervoltage) thresholds, GPIO configurations, control loop Kp, Ki values etc., These configurations are stored permanently in the internal EEPROM and used to initialize the device on every power-up/wake-up cycle.

Figure 1-1 shows the internal memory architecture of the MCx devices. Every EEPROM register has a corresponding mirror register in the RAM (shadow) region. On every power-up/wake-up, the device reads the EEPROM registers in to the corresponding shadow registers to initialize the device variables. The user can modify the shadow register values when the device is in idle state using I²C write to specific shadow registers. These modifications in the shadow registers are lost on device power reset or sleep entry. In case the modifications need to be stored permanently, the user has to issue an EEPROM write command to copy the modified values from shadow registers to the EEPROM. The EEPROM contents can be read in to the corresponding shadow registers by issuing an EEPROM read command.

Figure 1-1 MCx Interface Circuit With Host Microcontroller or Processor

The EEPROM read and write commands can be issued by a host microcontroller over I²C wherein the host acts as the primary device and MCx acts as the secondary device in the I²C communication as shown in Figure 1-1. Refer to device data sheet for details on the I²C protocol.