Can I buy and sell shares across the two exchanges?
You will be able to place an MIS buy order in one exchange and an MIS short order in the other. However, by the end of the trading day, both these trades are required to be squared off individually on each exchange.
If you hold shares of a company which trades in both the exchanges, you can sell it on one exchange and buy it back on a different exchange. Even if these trades are in the CNC category, all charges including the STT will be that of an intraday trade.