The diagnostic/enable pins are pulled high on the board and can be left disconnected if you do not want to monitor the fault conditions of the motor driver chip. INA and INB control the direction of the motor, and the PWM pin turns the motor outputs on or off, allowing you to control motor speed with a supplied pulse width modulation (PWM) signal. The PWM pin is pulled low on the board, so the motor driver outputs are effectively disabled by default; the INA and INB pins are floating (they are not pulled to any particular default voltage). See the truth tables in the VNH2SP30/VNH3SP30 datasheet for more information on how the INA, INB, and PWM pins affect the driver outputs, OUTA and OUTB.
ENA/DIAGA: Status of high side and low side switches A; open drain output
Status of high side and low side switches A; open drain output.
Open drain bidirectional logic pins. These pins must be connected to an external pullup resistor. When externally pulled low, they disable half-bridge A or B. In case offault detection (thermal shutdown of a high side FET or excessive ON state voltagedrop across a low side FET), these pins are pulled low by the device (see truth tablein fault condition).
niente nessun problema, era perchè non c'era il carico collegato...