This is a special purpose boot loader for a system I've called Proto-Sys. Eventually it is going to become a 64 bit application that will encompass all the resources to hook into drivers, benchmark code and optomize algorithms.
* Preserve registers as they were passed by BIOS * Create a 64K stack frame just below BDA * Reserve 192 bytes for scratch area at top of frame pointed to by SS:BP * Load remainder of the lowest density disk (7 sectors) * Move that 4K image lower in memory. In this case 6A:0 * Build an E820 memory map starting @ 50:0 * Test and turn on A20 using fast A20 gate
Fundementally, I just like experimenting with algorithms as a hobby, so you may see some unorthodox methodolgy, but generally this code does reinforce the concept of segmented memory in real or 16 bit. In the next stage, I'll be going into protected mode and that is where all the details of the machines state will be displayed. If any of you have legacy hardward, post 80286, I would appreciate you testing this code on your systems.
Even if you don't have real hardware, it would be interesting too as I use BOCHS 2.6.5