There is a little known extension known as "EPP BIOS" which gives better
control over the parallel port. The actual location is found by a call to INT 17h
(BIOS printer location) which then returns a "real mode" address to the BIOS
address space.
Advantages:
a) Avoid the need for wild IRQ probes
b) Change parallel port modes reliably without stumbling around looking for
the IO chipset in wierd and wonderful locations.
Disadvantages:
a) EPP BIOS can only be accessed from real mode (urk!)
Below is an abstract from the API specs.
==================
A.4.3 Set Mode
Set Mode is used to set the operating mode of the EPP port. This call can
only be made while the CPU is operating in real mode.
==================
David Campbell
<nofill>
=======================================================
campbell@torque.net
Current project list:
a) Maintain Linux ZIP drivers
b) Create Linux chipset specific parport drivers
c) Start on ParSCSI drivers
Any assistance to clearing this list most welcome
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