L6472 STMICROELECTRONICS [STMicroelectronics], L6472 Datasheet - Page 57

• Manufacturer Part Number: L6472
• Description: dSPIN fully integrated microstepping motor driver
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

L6472
9.2.5
Note:
9.2.6
Any attempt to read an inexistent register (wrong address value) causes the command to be
ignored and WRONG_CMD flag to rise at the end of command byte as if an unknown
command code is sent.
Run (DIR, SPD)
Table 37.
The Run command produces a motion at SPD speed; the direction is selected by the DIR
bit: '1' forward or '0' reverse. The SPD value is expressed in step/tick (format unsigned fixed
point 0.28) which is the same format as the SPEED register (see
The SPD value should be lower than MAX_SPEED and greater than MIN_SPEED
otherwise the Run command is executed at MAX_SPEED or MIN_SPEED respectively.
This command keeps the BUSY flag low until the target speed is reached.
This command can be given anytime and is immediately executed.
StepClock (DIR)
Table 38.
The StepClock command switches the device in step-clock mode (see
imposes the forward (DIR = '1') or reverse (DIR = '0') direction.
When the device is in step-clock mode the SCK_MOD flag in the STATUS register is raised
and the motor is always considered stopped (see
The device exits from step-clock mode when a constant speed, absolute positioning or
motion command is sent through SPI. Motion direction is imposed by the respective
StepClock command argument and can by changed by a new StepClock command without
exiting step-clock mode.
Events that cause bridges to be forced into high-impedance state (overtemperature,
overcurrent, etc.) do not cause the device to leave step-clock mode. StepClock command
does not force the BUSY flag low. This command can only be given when the motor is
stopped. If a motion is in progress the motor should be stopped and it is then possible to
send a StepClock command.
Any attempt to perform a StepClock command when the motor is running causes the
command to be ignored and the NOTPERF_CMD flag to rise (see
Bit 7
Bit 7
X
0
0
Bit 6
X
1
Bit 6
Run command structure
StepClock command structure
1
Bit 5
X
0
Bit 5
0
Bit 4
X
1
Doc ID 022729 Rev 1
Bit 4
1
SPD (Byte 1)
SPD (Byte 0)
SPD (Byte 2)
Bit 3
Bit 3
1
0
Section 6.7.5
Bit 2
0
Bit 2
0
Bit 1
0
Bit 1
and 9.1.18).
0
Section
Section
Programming manual
Bit 0
DIR
Section
Bit 0
DIR
9.1.4).
9.1.19).
6.7.5) and
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