No notice of dishonour is necessary--

(a) when it is dispensed with by the party entitled thereto;

(b) in order to charge the drawer, when he has countermanded payment;

(c) when the party charged could not suffer damage for want of notice;

(d) when the party entitled to notice cannot after due search be found; or the party bound to give notice is, for any other reason, unable without any fault of his own to give it;

(e) to charge the drawers, when the acceptor is also a drawer;

(f) in the case of a promissory note which is not negotiable;

(g) when the party entitled to notice, knowing the facts, promises unconditionally to pay the amount due on the instrument.