Meromorphic linear system of ordineary differential equations with Poncare rank 1 appears in the construction of Dubrovin's Frobenius manifold and also Bridgeland stability condition etc. Its isomonodromy deformation is an important source of higher rank Painleve systems. In this talk, we first give the long time asymptotic behavior of the generic solutions of the isomonodromy equation, and their boundary values. We then write down the explicit formula of the monodromy data of the associated linear system via the boundary values. We mention some applications of the results in WKB analysis, representation theory and the study of Frobenius manifolds. Based on a joint work with Qian Tang.