STMicroelectronics Fully integrated stepper motor driver mounting the L6472 in a high power PowerSO package EVAL6472PD EVAL6472PD Data Sheet

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This command can only be given when the previous motion command has been completed 
(BUSY flag released).  

Any attempt to perform a GoTo command when a previous command is under execution 
(BUSY low) causes the command to be ignored and the NOTPERF_CMD flag to rise 
(see 

         

The GoTo_DIR command produces a motion to the ABS_POS absolute position imposing 
a forward (DIR = '1') or a reverse (DIR = '0') rotation. The ABS_POS value is always in 
agreement with the selected step mode; the parameter value unit is equal to the selected 
step mode (full, half, quarter, etc.).

The GoTo_DIR command keeps the BUSY flag low until the target speed is reached. This 
command can only be given when the previous motion command has been completed 
(BUSY flag released).

Any attempt to perform a GoTo_DIR command when a previous command is under 
execution (BUSY low) causes the command to be ignored and the NOTPERF_CMD flag to 
rise (see 

         

The GoUntil command produces a motion at SPD speed imposing a forward (DIR = '1') or
a reverse (DIR = '0') direction. When an external switch turn-on event occurs (see 

), the ABS_POS register is reset (if ACT = '0') or the ABS_POS 

register value is copied into the MARK register (if ACT = '1'); the system then performs a 
SoftStop command.

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 target speed is imposed at MAX_SPEED or MIN_SPEED respectively.

Bit 7 

Bit 6 

Bit 5 

Bit 4 

Bit 3 

Bit 2 

Bit 1 

Bit 0 

0  1  1  0 1 0 0 

DIR 

From 

host 

X 

X 

ABS_POS (Byte 2) 

From host 

ABS_POS (Byte 1) 

From host 

ABS_POS (Byte 0) 

From host 

1 0 0 0 

ACT 

0 1 

DIR 

From 

host 

X X X X 

SPD 

(Byte 

2) 

From 

host 

SPD (Byte 1) 

From host 

SPD (Byte 0) 

From host