8-Bit Software

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8FA4 '*'-Command

Submitted by Steve Fewell

Description:

Update the BASIC Text Pointer A address (&0B-&0C) to include the PTR A offset value (in Y) (i.e. add Y to PTR A).
BASIC Text pointer A now points to the start of the '*' command.
Set X (LSB - &0B) and Y (MSB - &0C) to the address of BASIC Text pointer A.
Call OSCLI (&FFF7) to execute the Operating System ('*') command.
Continue to &8FAE to skip the rest of the line and execute the next command line or program statement (or to return to
the command line prompt if the program has finished or we were not running a program.


Disassembly for the '*'-Command routine

8FA4   032 188 155 20 BC 9B JSR &9BBC Update BASIC Text pointer A (Add offset value & then reset offset to 1)
8FA7   166 011 A6 0B LDX &0B
8FA9   164 012 A4 0C LDY &0C
8FAB   032 247 255 20 F7 FF JSR &FFF7   OSCLI
8FAE   ...Execute next command line / program statement...

 


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