::SHE+ILA::'s Virtual CPU Engine [$78]

More about ::SHE+ILA::'s Virtual CPU Engine [$78]

The output from the Parser is a parse tree of instructions (opcodes) and data items (Bufs). This is put in a system queue, in order to avoid the INT $09 driven Parser task needing to generate forks (deferred lower-priority interrupt procedures). This queue is read by ::ILA::, the Virtual CPU (Interactive Language Architecture). Bytes $E4 though $FF are interpreted as instructions, while $20 through $7F are characters and $80 through $E3 are packed decimal numerics. Segment data access is done via the FBI (Fundamental Buffer Interface) to ::SHE:: (Segmented Hierarchical Environment) which accesses extended memory and the swapfile via VM86 protected mode. See the #sheila hashtag descriptions for full system documentation. ::SHE+ILA:: requires a 100% IBM compatible PC; many modern clones do not implement many of the BIOS calls which I have used in order to avoid copyright and patent infringement. So don't throw away your old retro hardware :)