BIAS is a ZX Spectrum assembler which interacts with the BASIC system
to provide a flexible programming environment.  It contains several
nonstandard features such as the inclusion of split-IX instructions and
Spectrum floating point calculator operations.  It is fully relocatable.

Full instructions and a binary are contained within the zip file.  The
binary consists of just the assembler code.  This can be loaded into the
"xzx" Spectrum emulator, for example, by defining LOAD_SAVE_2 and using
the BASIC instruction LOAD "bias.bin" CODE nnnnn.

Two code files in xzx tape file format are also provided for conversion
from other assemblers.  "gens2pro" is for Hisoft GENS  assembler source
files, and "asm2pro" is for  EDTASM source files.  Both files load in
at 64000 and have the same calling sequence:

PRINT USR 64000,start_of_text

The result will be a program which, with some editing to remove the
assembler options, is suitable for input to BIAS.

xzx tape file format files contain the following:

 bytes 0-3:  the characters "ZXF1"
 bytes 4-20: a spectrum tape header
 bytes 21-:  the actual file

so the binary can be recovered by stripping off the first 21 bytes.

Ian Collier
imc@comlab.ox.ac.uk