I created a Image file using paint, It's in ascii format. I would like to store these in flash Ram to be access by my 8051.

If your 8051 can recognize that format, then why convert to hex? just to program it in the chip??

Most of the universal programmer softwares can load binary file as well. Just load this BMP/ASCII as a binary file, and program it.

If you need the first byte to be at 40h, the programmer softwares have an option for offset. Use it

IA