Memory Size; Bootstrap Loader - Tandy 1000 SL Technical Reference Manual

BIOS Services
Memory Size
This service returns the total number of kilobytes of RAM in the com-
puter system (contiguous starting from Address 0) in the AX register.
The maximum value returned is 640.
Software Interrupts
12 hex (18 dec)
Bootstrap Loader
Track 0, Sector 1 is read into Segment 0, Offset 7COO.
Control is then transferred as follows: (CS)
=
OOOOH
(IP)
=
7COOH
(DL)
-
drive where bootstrap sector was read
Software Interrupts
19 hex (25 dec)
39.