Thank you for your reply.
Do you mean to use UniFlash as the programmer software?
Install the newly purchased TMS320F2812GHHA (no firmware inside) on the PCB circuit board,Then connect the JTAG interface and PCB circuit board through XDS110,Is this what writing firmware means?
As a side note, does UniFlash support files in the format (.x00)? XDS110 seems to be available in V1, V2, and V3. Which version should I choose?