On 04/07/2016 18:00, Kevin O'Connor wrote:
So, if I read the sgabios code correctly, it allocates a buffer of:
struct { u8 x, y; char c; } logbuf[256]; int logbuf_offset;
Every character sent on the serial port is appended to "logbuf" in order, wrapping if necessary: logbuf[logbuf_offset++ % 256] = x, y, c. On a read, it scans backwards from logbuf_offset to find the last update to that cell.
Interestingly, it doesn't store the attribute with the character - it's int1008 handler just returns the last attribute used anywhere on the screen.
The code is only used if it is the sole vga code (as opposed to being used in addition to an existing vgabios).
Does anyone know where one can find the original svn commit history for sgabios? Seems the original google code repo is no longer present.
There was no history as far as I remember, mostly a code drop.
Paolo