On Jan 13, 2005, at 1:31 am, Aley Keprt wrote:
I have a little technical question: How does Sam ROM know whether the file no.01 is DOS, or not? It doesn't blindly load anything there, is it? Does "bootable" disk have some special contents in track 0, sector 1? Or possibly the special contents are at track 4, sector 1? (I'd expect there is something at track 0, sector 1, but I'm not sure what exactly. Please tell me.)
It loads track 4 sector 1 and expects to find "BOOT" (T is "T"+128) in bytes 256->259. If so, it pages it into section C and calls 32777 (to allow for the 9 byte file header at the start of the sector), which is enough to contain the routines which go on to load the rest of the file.
HTH,
Andrew
-- --- Andrew Collier ---- ---- http://www.intensity.org.uk/ --- -- Have you lost your Marbles? http://www.marillion.com/
