Modifications

== Introduction ==

== Introduction ==

The Romi 32U4 Control Board includes battery terminal connections that provide access to power from the Romi chassis’s six-AA battery compartment. We recommend using rechargeable AA NiMH cells, which results in a nominal voltage of 7.2 V (1.2 V per cell). You can also use alkaline cells, which would nominally give you 9 V.

La carte de contrôle Romi 32U4 inclus des bornes de connexion pour accéder au l'alimentation offerte par le compartiment à pile (6 piles AA). Pololu recommande d'utiliser des piles AA rechargeables NiMH, qui offrent une tension nominale de 7.2 V (1.2 V per pile). Vous pouvez également utiliser des piles Alcaline qui offre, dans ce cas, une tension nominale de 9 V.

The negative battery voltage is connected to GND. The positive battery voltage is designated '''VBAT'''. VBAT feeds into a reverse protection circuit and then a power switching circuit controlled by the on-board pushbutton or slide switch. The output of the power switching circuit is designated '''VSW'''.

Le pôle négatif des piles est connecté sur la masse/GND. Le pole positif des piles est désigné par la mention '''VBAT'''. VBAT passe par une diode de protection (contre la polarisation inverse) et alimente ensuite le convertisseur de tension contrôlé par le bouton (ou interrupteur) présente sur la carte. La sortie du circuit d'alimentation est identifié à l'aide de '''VSW''' (''Volt SWitch'' pour alimentation avec interrupteur).

VSW provides power to the motors through the on-board DRV8838 motor drivers, so the motors can only operate if the batteries are installed and the power switch circuit is on.

VSW fournit la puissance aux moteurs par l'intermédiaire du contrôleur moteur DRV8838, de sorte que les moteurs peuvent uniquement fonctionner que si les piles sont installées et que l'interrupteur d'alimentation est fermé.

The reverse protected and switched battery voltage on VSW can be monitored through a voltage divider that is connected to '''analog pin 1''' (PF6) by default. The divider outputs a voltage that is equal to one third of the battery voltage, which will be safely below the ATmega32U4’s maximum analog input voltage of 5 V as long as the battery voltage is less than 15 V (though the maximum voltage for the board is still limited to 10.8 V by the DRV8838 motor driver). The {{fname|readBatteryMillivolts()}} function in the Romi32U4 library can be used to determine the battery voltage from this reading. The surface-mount jumper labeled “A1 = BATLEV” can be cut to disconnect the voltage divider and free the pin for other uses.

The reverse protected and switched battery voltage on VSW can be monitored through a voltage divider that is connected to '''analog pin 1''' (PF6) by default. The divider outputs a voltage that is equal to one third of the battery voltage, which will be safely below the ATmega32U4’s maximum analog input voltage of 5 V as long as the battery voltage is less than 15 V (though the maximum voltage for the board is still limited to 10.8 V by the DRV8838 motor driver). The {{fname|readBatteryMillivolts()}} function in the Romi32U4 library can be used to determine the battery voltage from this reading. The surface-mount jumper labeled “A1 = BATLEV” can be cut to disconnect the voltage divider and free the pin for other uses.