Hi Naoki,
When you say no response, do you mean the current level is not changing according to the Vref/Rsense equation or there is no response from the motor position?
In normal case, if the motor is kept the state, the change on Vref will change both the current of A and B propotionally. Since using half stepping, there will be 50% chance that only one coil is excited with current. So is that possible when we do the test of the "no response " happened to be the zero one? So it will not responsed to the change on the Vref as it always zero.
Other possibility is that the driver is in SLOW decay mode, and the current is actually not correctly controlled by the regulation loop because of the current injected in Tblanking time cannot be decay down to the setting level. In this case, motor may be runnning but the current is already out of control most of the time.
Best regards,
When you say no response, do you mean the current level is not changing according to the Vref/Rsense equation or there is no response from the motor position?
In normal case, if the motor is kept the state, the change on Vref will change both the current of A and B propotionally. Since using half stepping, there will be 50% chance that only one coil is excited with current. So is that possible when we do the test of the "no response " happened to be the zero one? So it will not responsed to the change on the Vref as it always zero.
Other possibility is that the driver is in SLOW decay mode, and the current is actually not correctly controlled by the regulation loop because of the current injected in Tblanking time cannot be decay down to the setting level. In this case, motor may be runnning but the current is already out of control most of the time.
Best regards,