+
+ /* FIXME: the arbitration of I2C interrupts are not vetted. If, for example
+ * the UCALIFG bit gets set and neither it nor the corresponding interrupt
+ * enable bit is never unset, then an ISR configured for UCSTTIFG or
+ * UCSTPIFG will never be signalled.
+ */
+
+ } else if (READ_FLAG(UCB1STAT, UCALIFG)) {
+ CLR_FLAG(UCB1STAT, UCALIFG);