Programming manual
powerSTEP01
11.1.13 FN_SLP_ACC
This register is specific for voltage mode driving (see Section 8).
The FN_SLP_ACC register contains the BEMF compensation curve slope that is used when
the speed is greater than the intersect speed during acceleration (Section 8.4 for details). Its
value is expressed in s/step and the available range is from 0 to 0.004 with a resolution of
0.000015.
When ST_SLP, FN_SLP_ACC and FN_SLP_DEC parameters are set to zero, no BEMF
compensation is performed.
Any attempt to write the register when the motor is running causes the command to be
ignored and the NOTPERF_CMD flag to rise (Section 11.1.28).
11.1.14 FN_SLP_DEC
This register is specific for voltage mode driving (see Section 8).
The FN_SLP_DEC register contains the BEMF compensation curve slope that is used when
the speed is greater than the intersect speed during deceleration (Section 8.4 for details). Its
value is expressed in s/step and the available range is from 0 to 0.004 with a resolution of
0.000015.
When ST_SLP, FN_SLP_ACC and FN_SLP_DEC parameters are set to zero, no BEMF
compensation is performed.
Any attempt to write the register when the motor is running causes the command to be
ignored and the NOTPERF_CMD flag to rise (Section 11.1.28).
11.1.15 K_THERM
This register is specific for voltage mode driving (see Section 8).
The K_THERM register contains the value used by the winding resistance thermal drift
compensation system (Section 8.6).
The available range is from 1 to 1.46875 with a resolution of 0.03125, as shown in Table 16.
Table 16. Winding resistance thermal drift compensation coefficient
K_THERM [3..0]
Compensation coefficient
0
0
0
0
0
0
0
1
1
1.03125
1
1
1
1
1
1
0
1
1.4375
1.46875
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STMICROELECTRONICS [ ST ]
