STMicroelectronics Fully integrated stepper motor driver mounting the L6472 in a high power PowerSO package EVAL6472PD EVAL6472PD データシート
製品コード
EVAL6472PD
DocID022729 Rev 3
57/70
L6472
Programming manual
70
This command reads the current PARAM register value; PARAM is the respective register
address listed in
address listed in
.
The command response is the current value of the register (most significant byte first). The
number of bytes composing the command response depends on the length of the target
register (see
number of bytes composing the command response depends on the length of the target
register (see
).
The returned value is the register one at the moment of GetParam command decoding. If
the register value changes after this moment, the response is not accordingly updated.
the register value changes after this moment, the response is not accordingly updated.
All registers can be read anytime.
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.
ignored and WRONG_CMD flag to rise at the end of command byte as if an unknown
command code is sent.
9.2.5
Run (DIR, SPD)
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
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
Note:
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.
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.
9.2.6 StepClock
(DIR)
The StepClock command switches the device in step-clock mode (see
) and 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
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
motion command is sent through SPI. Motion direction is imposed by the respective
Table 38. Run command structure
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0 1 0 1
0
0 0
DIR
From
host
X X X X SPD
(Byte
2)
From
host
SPD (Byte 1)
From host
SPD (Byte 0)
From host
Table 39. StepClock command structure
Bit
7 Bit
6 Bit
5 Bit
4 Bit 3
Bit 2
Bit 1
Bit 0
0 1 0 1 1 0 0
DIR
From
host