Which Axis Parameters are automatically restored from EEPROM after a power-on reset on the TMCM-1640?
The firmware manual for this device contains a table of all axis parameters (APs) in Section 5. This table contains a column titled "Access". If this column contains the letter "E", then that axis parameter can be permanently saved to EEPROM. On power-up, the value in EEPROM will be automatically copied into RAM where it will take effect.
The "STAP" command should be used to store a value into EEPROM for these APs with an "E" access type.
First, you must set the axis parameter using the SAP command. Then, issue an STAP command targeting this same AP, and its value will be stored in non-volatile memory. This value will be automatically set when the device powers on.
You can also manually copy the contents of EEPROM to it's corresponding AP by using the RSAP command.
APs without the "E" access type cannot have their values stored in EEPROM, meaning you cannot use the STAP command on these APs. You can still use the RSAP to reset this AP to its startup value, but you cannot change the startup value.
More information on STAP and RSAP commands are available in the firmware manual for this device.