#define GPIO 0xb8000060
#define GPIO_LED_CISCOWHT 8

        li      s0, GPIO
        li      s1, GPIO_LED_CISCOWHT
        neg     s1
        addi    s1, s1, -1
        lw      s2, 4(s0)
        and     s2, s2, s1
        sw      s2, 4(s0)
