From ba66b73ce7b4b83ba5dc0fe80695d2fbdd66dd80 Mon Sep 17 00:00:00 2001 From: Andreas Baumann Date: Sun, 14 May 2017 18:45:47 +0200 Subject: added some docu and a design document --- DESIGN | 15 +++++++++++++++ src/README | 2 ++ 2 files changed, 17 insertions(+) create mode 100644 DESIGN diff --git a/DESIGN b/DESIGN new file mode 100644 index 0000000..b7ba1e2 --- /dev/null +++ b/DESIGN @@ -0,0 +1,15 @@ +design principles +----------------- + +Use strict ANSI C99. This means no inline-assembly. This means +we have to write assembly routines if we need things not available +in C (lgdt, in, out, etc.). + +Make sure it compiles with every ANSI C99 compiler (gcc, clang, tcc, ...). + +Use only very simple makefile rules. Make sure we could also just +use a simple shell script to compile the kernel. + +Avoid implementation and using of unsafe C functions. Provide safe +counterparts wherever possible. There are of course exceptions like +scrolling the VGA buffer with a memmove. diff --git a/src/README b/src/README index f0081b7..bfd0795 100644 --- a/src/README +++ b/src/README @@ -10,7 +10,9 @@ * magic.asm kernel utility routines +* console.c - the kernel console, can use VGA or serial port for now * vga.c - VGA basic output routines for early kernel output +* serial.c - serial output to COM1 (only sequential ASCII chars, no terminal) * port.c, port.asm - I/O ports C library routines -- cgit v1.2.3-54-g00ecf