Tracing the parallel port is in general much more difficult than tracing scsi. There are several reasons for this:

• Most access is done direct, so you can not plug in some logging stuff.
• The timing is sometimes cruical. Low level debuggers like softice change this when logging port i/o.
• You can not use a second parallel port for tracing because you are to slow to see everything

There are several solutions to solve those problems.

• Insert a logging dll between the program and the actual dll
• Use special patched WINE
• use a logic analyzer
• use softice
• buy a scsi scanner

Following commands were used:

macro dumpit ="db C004A000 L6020;ed C004A000 C004A010;f C004A000 L6000 00; x"

bpx vpm2xd+19f8 if *(C004A000)>=C0050000 do "dumpit"
bpx vpm2xd+1837 if *(C004A000)>=C0050000 do "dumpit"