This documents contains updates/corrections to publication SA34-2206:
"4777 Magnetic Stripe Unit and 4778 PIN-Pad Magnetic Stripe Reader
 DOS Programming Guide"


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;; Following information is an addition to Chapter 2, pages 2-2 and 2-3.   ;;
;; It explains the /Axxxx and /Qxx parameters.                             ;;
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 1. Following are the defaults the driver assumes when
    you specify /C1 thru /C4:

    Option    Irq      Addr               Com Port Addr
    ------    ----     ----               -------------
     /C1      Irq 4    3F8h       Port address at BIOS 40:0 area
     /C2      Irq 3    2F8h       Port address at BIOS 40:2 area
     /C3      Irq 3    3E8h       Port address at BIOS 40:4 area
     /C4      Irq 3    2E8h       Port address at BIOS 40:6 area

    Our driver will zero out the corresponding BIOS 40:x area
    after acquiring the port. To insure proper setup, you may
    want to verify the BIOS area before loading our driver.

 2. Instead of using the /C1 thru /C4 option, you can specify
    the Irq and port address by using the following options
    on the device= statement for the Serial driver being used:

     /A:xxxx - where xxxx is the Hex Comm port I/O addresss to use.
     /Q:xx   - where xx is the Decimal Interrupt level to use.
               (valid Int levels are 02, 03, 04, 05, 10, 11, or 15)

    When using the /Axxxx option, our driver does not zero out
    any of the BIOS area.

 3. NOTE: you must perform the BIOS setup on your PC or configure
    the expansion serial port adapter to match the Irq/Port that
    our driver will be using as described above.

    NOTE: In ISA/PCI bus machines (non microchannel), you must
    insure that our driver is using an Interrupt that is NOT being
    used by any other driver or device. Interrupt levels can't be
    shared in ISA/PCI bus PC's.