okjb: Black has to stop chasing your cannon, otherwise he will lose the game, see http://www.clubxiangqi.com/rules/d32to38.htm

okjb: My rule book : The draw rule is the most complicated in Chinese chess and in fact has not yet been formalized. The reason for this is that perpetual check and perpetual repetition of moves are quite common possibilities in Chinese chess.
In fact, if players were allowed to force a draw by perpetual repetition of position, as they are in international chess, then almost every fairly evenly contested game of Chinese chess would end in a draw.
As a result, perpetual check is almost absolutely prohibited. Generally, the player giving perpetual check is required to make some other move instead. The catch is about this word 'generally' . If the player can prove that he is being forced by his opponent to give perpetual check, then the game might be ruled a draw.