powerSTEP01
Programming manual
Any attempt to write to the register when the motor is running causes the command to be
ignored and the NOTPERF_CMD flag to rise (Section 11.1.28).
11.1.6
DEC
The DEC register contains the speed profile deceleration expressed in step/tick2 (format
unsigned fixed point 0.40).
In order to convert the DEC value in step/s2 the following formula can be used:
Equation 6
DEC ⋅ 2–40
[step/s2]= ----------------------------
tick2
where DEC is the integer number stored in the register and tick is 250 ns.
The available range is from 14.55to 59590 step/s2 with a resolution of 14.55 step/s2.
When the device is working in infinite acceleration mode this value is ignored.
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).
11.1.7
MAX_SPEED
The MAX_SPEED register contains the speed profile maximum speed expressed in
step/tick (format unsigned fixed point 0.18).
In order to convert it in step/s, the following formula can be used:
Equation 7
MAX_SPEED ⋅ 2–18
[step/s]= ----------------------------------------------------
tick
where MAX_SPEED is the integer number stored in the register and tick is 250 ns.
The available range is from 15.25 to 15610 step/s with a resolution of 15.25 step/s.
11.1.8
MIN_SPEED
The MIN_SPEED register contains the following parameters:
Table 13. MIN_SPEED register
Bit 12
Bit 11 Bit 10 Bit 9 Bit 8 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
LSPD_OPT
MIN_SPEED
The MIN_SPEED parameter contains the speed profile minimum speed. Its value is
expressed in step/tick and to convert it in step/s the following formula can be used:
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