In reply to nikhilverif:
I did still not get your point.
You have 7 registers: reg1, …, reg5, ind_reg, data_reg. Correct?
Which addresses do they have? Are there fixed addresses?
If you say you have to split the command write(reg1) into ot writes to 2 registers, the ind_reg and the data_reg, what does it menan for writing reg2?