Functional description
L6472
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DocID022729 Rev 5
6.17 BUSY\SYNC
pin
This pin is an open drain output which can be used as the busy flag or synchronization
signal according to the SYNC_EN bit value (STEP_MODE register).
6.17.1
BUSY operation mode
The pin works as busy signal when the SYNC_EN bit is set low (default condition). In this
mode the output is forced low while a constant speed, absolute positioning or motion
command is under execution. The BUSY pin is released when the command has been
executed (target speed or target position reached). The STATUS register includes a BUSY
flag that is the BUSY pin mirror (see
In the case of daisy chain configuration, BUSY pins of different ICs can be hard-wired to
save host controller GPIOs.
6.17.2
SYNC operation mode
The pin works as a synchronization signal when the SYNC_EN bit is set high. In this mode
a step-clock signal is provided on the output according to a SYNC_SEL and STEP_SEL
parameter combination (see
).
6.18 FLAG
pin
By default an internal open drain transistor pulls the FLAG pin to ground when at least one
of the following conditions occur:
Power-up or standby/reset exit
Overcurrent detection
Thermal warning
Thermal shutdown
UVLO
Switch turn-on event
Wrong command
Non-performable command.
It is possible to mask one or more alarm conditions by programming the ALARM_EN
register (see
). If the corresponding bit of the ALARM_EN register is
low, the alarm condition is masked and it does not cause a FLAG pin transition; all other
actions imposed by alarm conditions are performed anyway. In the case of daisy chain
configuration, the FLAG pins of different ICs can be OR-wired to save host controller
GPIOs.