EPSPRINT.DOC File

                  (c)  Hewlett-Packard Company, 1990


OVERVIEW
--------

The EPSPRINT library enables you to print a graphics object on an
Epson serial printer, such as the FX-80 and FX-85 printers.

[See PCLPRINT.LIB on this disk if you have an HP LaserJet, DeskJet, or
 any other printer whose "escape codes" are HP Printer Command
 Language compatible.  -jkh-]

When attached to the HOME directory, the library is named EPPRT.  (An
{EPPRT} menu label is visible in the LIBRARY menu.)  Two commands in
the library, EPON and MAG, add an extra sublist of parameters as the
fifth element in the HP 48 reserved variable PRTPAR.  These parameters
store information needed by your HP 48 to print graphics objects to
the Epson printer.  In order of occurrence in the sublist, they are as
follows:

  o  The real number 1, which indicates Epson printer type.  

  o  A real number (1, 2, or 4), which represents the magnification.  This
     is controlled by the MAG command and has a default setting of 2, which
     tells the library to expand each pixel in the graphics object to a 2x2
     square on the printer.

  o  A string containing the escape sequence sent before a graphics object
     is printed.  The default begin sequence is "<esc>A<08>", which tells
     the printer to set its line spacing to 8 dot rows.  The only way to
     change this is to edit PRTPAR. 

  o  A string containing the escape sequence sent after a graphics object is
     printed.  The default end sequence is "<esc>2", which sets the printer
     to its default state of 6 lines per inch.  The only way to change this
     is to edit PRTPAR. 

  o  A string containing the escape sequence sent before each line of
     graphics data.  This sequence, which specifies the density of the
     graphics, defaults to "<esc>K", telling the printer to do single-
     density graphics.  The possible density sequences are as follows:

          <esc>K     Single density (60 DPI) graphics.  

          <esc>L     Double density (120 DPI) graphics. 

          <esc>Y     High-speed, double density (120 DPI) graphics. This
                     setting has some restriction on the data printed.  

          <esc>Z     Quadruple density (240 DPI) graphics.  This setting
                     has some restrictions on the data printed.  

     The only way to change the default sequence of <esc>K is to edit PRTPAR.


PROCEDURE
---------

Here are the steps to follow to transfer the Library into your calculator and
print an HP 48 graphics object on an Epson compatible printer:

 1.  Transfer the EPSPRINT.LIB file from the computer to your calculator.  The
     menu label {EPSPR} will appear in your HP 48 VAR menu.

 2.  Attach the library to your HOME directory:

       A.  Press the VAR menu label {EPSPR} to recall the library to the
           stack.

       B.  Enter the port number where you want the library to reside--0,
           1, or 2.

       C.  Execute STO.

       D.  Turn the HP 48 off and then on again.  {EPPRT} attaches itself and
           appears as a library in the LIBRARY menu.

 3.  Using the serial cable 25-pin adapter and a male/male converter (not
     included), connect the HP 48 to the Epson printer.  

 4.  Set the HP 48 baud (using the I/O SETUP menu) and the printer baud to
     match each other. Set the printer to use XON/XOFF handshaking.

 5.  Execute EPON (press [left-shift][LIBRARY] {EPPRT} {EPON}).  [Be
     sure to execute EPOFF before removing EPSPRINT.LIB from memory!
     -jkh-]

 6.  Optionally execute MAG. (See the description of MAG below.) 

 7.  Execute one of the HP 48 print commands for printing graphics objects--
     PRLCD, PR1, or PRVAR. ([ON][PRINT] does not work and should be avoided.)

 8.  If you wish to switch back to printing on the HP 82240 Infrared Printer, 
     execute EPOFF (press [left-shift][LIBRARY] {EPPRT} {EPOFF}).


COMMAND SUMMARY
---------------

These commands are contained in the PCL library:

  o  EPON:  Enables special graphics printing and adds the previously
     explained sublist to PRTPAR.  Also sets flag -34 and clears flag -33
     so that printing is directed to the wired serial port, and modifies
     IOPAR to enable transmit pacing (XON/XOFF) and to set parity to "none."

  o  EPOFF:  Disables special graphics printing and clears flag -34 (so
     that printing will be directed to an HP 82240B printer).  EPOFF does not
     change the sublist in PRTPAR--the magnification setting and other changes
     are preserved for the next time you execute EPON.

  o  MAG:  Takes a real number from level 1 and puts it in the magnification
     position in the sublist in PRTPAR.  Allowable arguments are 1, 2, or 4
     (the sign is ignored).  A magnification of N causes one pixel in the
     graphics object to be expanded to an NxN square on the printer.