Observations::
After a strong fall price is not able to break the previous high,
and price is exactly now @ support,looks like its weak @1600 levels.
if price breaks 1600 levels,price fall is observed upto 1580 and 1540 levels.
Don't go for sell in HDFCBANK, it may reverse at any place in this levels.
look here for buyside until bearish gap filled on above 1640 and 1680 levels.