ReadMe.txt File
PCI support in the OS/2 Parallel Port Device Driver
Version 1.00
March 16, 2001
(c) Copyright International Business Machines Corporation, 2001.
    All rights Reserved.

            Contents
            --------
        1.0 Introduction
        2.0 Implementation
        3.0 Installation
        4.0 Uninstall Instructions
        5.0 Copyright and Trademark Information

        1.0 Introduction
            ------------
The OS/2 Parallel Port Device Driver (PP DD) is a base DD that supports
the PP interface for OS/2. There are two distinct versions of the PP DD:

- PRINT01.SYS supporting PPs on (Extended) Industry Standard Architecture
              (ISA/EISA) and Peripheral Component Interconnect (PCI) PCs,
- PRINT02.SYS supporting PPs on Micro Channel Architecture (MCA) PCs.
 
Only one of these PP DDs will be resident for each PC running in OS/2.

        2.0 Implementation
            --------------
The PRINT01.SYS DD is modified to support PCI PPs. The PP DD supports
up to three PCI PPs in the Standard Parallel Port (SPP) mode.

By default the OS/2 PP DD uses the polling transmission method. If the
transmission protocol is changed to the interrupt method by specifying
the /IRQ parameter in the BASEDEV= command, then the PP DD supports PCI
PPs in an interrupt-driven manner.

In that case the PP DD attempts to set interrupt service routine (ISR)
for PCI IRQ to be not-shared at task time. If this attempt failed then
the PP DD sets ISR for PCI IRQ to be shared.

If additionaly the /SHR parameter is specified then the PP DD sets ISRs
for PCI IRQs to be shared at initialization time.

Interrupt sharing at the PP DD interrupt time is handled using interrupt
pending (occured) bit in the PCI PP status register.

        3.0 Installation
            ------------
The OS/2 PP DD with PCI support software consists of the following files:
- PRINT01.SYS           the PP DD with PCI support,
- PRTPCI.DDP            the PP DD Profile,
- READMEPCI.TXT         this file that you are reading.

Because the PP DD is a base DD, OS/2 determines the system's hardware
configuration and automatically installs and initializes the appropriate
PP DD. OS/2 adds a BASEDEV= command without parameters for the PP DD to
the CONFIG.SYS file.

The installation of the PP DD with PCI support is performed by replacing
the old PRINT01.SYS file in the directory \OS2\BOOT with the new file and
rebooting the system.

To perform the above operations the OS/2 DD Installation command (DDINSTAL)
can be used:
- Copy the OS/2 PP DD with PCI support files (see above) to the Device
  Support diskette or directory.
- Open an OS/2 window and enter DDINSTAL command to display the DD
  Installation window.
- Set in the Source directory field the Device Support diskette or
  directory.
- Set in the Destination directory field \OS2\BOOT directory on the hard
  disk with installed OS/2,
- Select Install if the Source directory and Destination directory are
  correct and you are ready to install the PP DD with PCI support.
  The DDINSTAL program uses information from the PP DD Profile file to add
  the necessary command to the CONFIG.SYS file and to copy all the PP DD
  with PCI support files into the \OS2\BOOT directory on the hard disk with
  installed OS/2.
- Verify BASEDEV=PRINT01.SYS command in the CONFIG.SYS file and add/change
  its parameters if necessary.
- Reboot the oprating system.

The PP DD with PCI support accepts four BASEDEV= command parameters:
three legacy parameters (/IRQ, /MPL, and /TOU:ddd) and new /SHR parameter.
The parameters can be specified in any combination of uppercase and
lowercase characters.

PARAMETER       FUNCTION

/IRQ            Directs the driver to use IRQs for printing rather than polling.

/SHR            This parameter in conjunction with /IRQ parameter directs the PP DD
                to service PCI IRQs as shared.

                NOTE: If your printer (for example, old dot matrix printer) generates
                IRQs without setting interrupt pending (occured) bit in PCI PP status
                register correctly then you cannot use PCI IRQ sharing and must not use
                /SHR parameter.

/MPL            Directs the driver to use modified polling for printing.
                This will help lower CPU utilization and enable better performance for other
                tasks while the printer is being accessed.

/TOU:ddd        Specifies maximum wait time in seconds before canceling
                the print request. This is a 3 decimal digit value (by default - 120 seconds).

        4.0 Uninstall Instructions
            ----------------------
To uninstall the OS/2 PP DD with PCI support:
- Remove or comment out the BASEDEV=PRINT01.SYS command from the
  CONFIG.SYS file.
- Remove the PP DD with PCI support files (see above) from the \OS2\BOOT
  directory on the hard disk with installed OS/2.
- Reboot the oprating system.

        5.0 Copyright and Trademark Information
            -----------------------------------
The following terms are trademarks of International Business Machines
Corporation in the United States and/or other countries:
        IBM
        OS/2
Other company, product, and service names may be trademarks or service
marks of others.