struct QEI_t{ int value; int delta; }; enum QEI_name_t{ QEI_A_NAME=0, QEI_B_NAME=1, QEI_C_NAME=2 }; extern struct QEI_t QEI_A, QEI_B, QEI_C; void QEI_update(void); void QEI_init(void); int QEI_get(enum QEI_name_t qei);