AR_ISR
isr = OS_REG_READ(ah, AR_ISR);
(void) OS_REG_READ(ah, AR_ISR); /* cleared on read */
OS_REG_WRITE(ah, AR_ISR, ~0); /* cleared on write */
isr = OS_REG_READ(ah, AR_ISR);
OS_REG_WRITE(ah, AR_ISR, ~0); /* cleared on write */
OS_REG_WRITE(ah, AR_ISR, ~0); /* cleared on write */
OS_REG_WRITE(ah, AR_ISR, isr);
OS_REG_READ(ah, AR_ISR);
isr = OS_REG_READ(ah, AR_ISR);
isr = OS_REG_READ(ah, AR_ISR);
OS_REG_WRITE(ah, AR_ISR, ~0); /* cleared on write */