Mirror of CollapseOS

Cronologia

Virgil Dupras 921a109749 stdio: little tweaks		5 anni fa
..
sms	sms/pad: make B jump to the next selection "class"	5 anni fa
README.md	Update docs w.r.t. its relationship with scas	5 anni fa
acia.asm	acia: protect DE during aciaInt	5 anni fa
blockdev.asm	Update comments	5 anni fa
blockdev_cmds.asm	blockdev: fix bug recently introduced in load cmd	5 anni fa
core.asm	shell: add support for backspace	5 anni fa
err.h	blockdev: make implementors "random access"	5 anni fa
fs.asm	zasm: fix include EOF detection	5 anni fa
fs_cmds.asm	fs: fix broken fopn on id > 0	5 anni fa
kbd.asm	kbd: make letters lowercase	5 anni fa
mmap.asm	blockdev: make implementors "random access"	5 anni fa
parse.asm	parse: fix option word default value	5 anni fa
pgm.asm	pgm: adapt to recent blkdev change	5 anni fa
sdc.asm	sdc: make sdcReadBlk return error on max retries	5 anni fa
shell.asm	stdio: add stdioReadC	5 anni fa
stdio.asm	stdio: little tweaks	5 anni fa
user.h.example	zasm emul: bring back kernel/user distinction	5 anni fa

README.md

Kernel

Bits and pieces of code that you can assemble to build a kernel for your machine.

These parts are made to be glued together in a single glue.asm file you write yourself.

This code is designed to be assembled by Collapse OS’ own zasm.

Defines

Each part can have its own constants, but some constant are made to be defined externally. We already have some of those external definitions in platform includes, but we can have more defines than this.

Each part has a “DEFINES” section listing the constant it expects to be defined. Make sure that you have these constants defined before you include the file.

Variable management

Each part can define variables. These variables are defined as addresses in RAM. We know where RAM start from the RAMSTART constant in platform includes, but because those parts are made to be glued together in no pre-defined order, we need a system to align variables from different modules in RAM.

This is why each part that has variable expect a <PARTNAME>_RAMSTART constant to be defined and, in turn, defines a <PARTNAME>_RAMEND constant to carry to the following part.

Thus, code that glue parts together could look like:

MOD1_RAMSTART .equ RAMSTART
#include "mod1.asm"
MOD2_RAMSTART .equ MOD1_RAMEND
#include "mod2.asm"