PCF8584_SCL_90
clock = PCF8584_CLK_3 | PCF8584_SCL_90;
clock = PCF8584_CLK_4_43 | PCF8584_SCL_90;
u_int8_t clock = PCF8584_CLK_12 | PCF8584_SCL_90;
uint8_t scl_val = PCF8584_SCL_90;