I haven't worked with block memories concept in Xilinx before. I want to put some simple numbers in a text file and save it. Then take those numbers and multiply by 2 and save in another file. I have written VHDL code but this is involving I/O so i have to use block RAM. But I have no clue about it. I have read tutorials and datasheet but still can't figure out how to do my task using BRAM. I am pasting my code with this question. Please let me know if we have to do some sort of programming for BRAM. when I am trying to compile the code, it is showing error that inFIle does not exist.
VHDL is not a programming language.
There are some programming-language-like features in VHDL (for example file IO), but these are only there to help write testbench code for simulation. When writing VHDL, don't think about coding software. Think about the hardware structure that you want to describe.
In hardware, there is no such thing as a "file". There is a hardware interface consisting of fixed signals (address, data, enables) to, e.g., a block RAM. You can read a word of data from the memory by specifying an address, but this will always be raw data.
To get the raw data into the block RAM, there will pretty much always be some software process running on an embedded or external CPU. The software running on the CPU can interpret the file system, and pass the relevant information for hardware-assisted processing to the hardware core (e.g., starting address in memory of data to be processed, length of data, parameterization of algorithm, etc.). Alternatively, there may be streaming data sources and sinks that pass through the hardware for processing.
This is what hardware is best at: processing a continuous stream of data and performing the same set of calculations on each data word.