Light curves and hardness ratios for observations I (left panel) and II (right panel) with a time resolution of P_I = 283.4532 s and P_II = 283.4447 s, respectively. Major off-states and major flares are indicated by arrows. Green points show the hardness ratio between the 3–5 keV and the 20–30 keV bands using the left-hand y axis. Magenta points show the hardness ratio between the 20–30 keV and the 40–78 keV bands using the right-hand y axis.