how will I know what are margins fixed on a day to day basis

Recently I have done a future purchase of Educomp at Rs. 1380 .
I got statement from my broker stating SPAN requirement margin and Gross Exposure margin. On contacting him he informed me that these margins change on a day to basis as determined by the exchange. However i would like to cross verify with exchange to check if the margins are correctly charged from me. Which is the source? I have gone in the site of BSE india but i could not get it

Im not sure of this but i think brokers mite have slightly varying margins for futures , but yes , there must be a fixed minimum margin from the exchange side , id like some clarity on the issue as well .. & btw , try nse not bse site for checking .