Welcome to Ben's page for the HP48.

Unlike most HP48 pages, this page does not have:
  • A list of my favorite games. (form your own opinions)
  • Dozens of links to other pages with HP48 stuff. (running slowly in circles)
It does, however have some useful and original things. They are:
  • A utility for converting binary to gray code written by me.
  • A Windows program that can make GROBs written by my brother.
So after that little rant, onward to the meat (and potatoes) of this page...

Gray Code Conversion Utilities

What the heck is Gray Code anyway?

Gray Code is a method of encoding a binary number so adding one only changes one digit.

Here is an example...

Binary Gray Code

Notice how only one digit changes when you add one.

What good is it?

Gray Code is useful in mechanical computers because it minimizes wear on mechanical switches.
It is also used for encoders because it makes the machining simpler.(So I'm told)
Link to here for a very important reason for using Gray Code.

Tell me more, tell me more...

Gray Code Conversion Utilities (GCCU) is a library for the HP48G/GX written by me.
It will convert any binary object to gray code and back to binary.
It allows you to give answers in binary or a string to keep you from accidentally adding them.

For more information email the author.

WOW!! This sounds like the coolest thing since frozen pizza, where can I get it?

Right here: GCCU.ZIP (1001 bytes)

Look in your 'User's Guide' (chapter 28) for instructions on how to attach libraries.

Graphic Viewer

What is Graphic Viewer?

Graphic Viewer is a program written by my brother that has many features.
Among other things it can take a computer graphics file and make it into a GROB for the HP48.

Here are some examples...

Graphic viewer can take a .GIF file and make it into a simple GROB

From this... to this...

Graphic Viewer can also make more complex images that require special software to view.

From this... to this...

They are really a bunch of GROBs that the program 'flips' through them to simulate a greyscale image.

It is really this...

Sounds like good stuff, where can I get it?

It is available from two places:

Or for more information you can visit its homepage at:

What about the special software that you mentioned?

There are two commonly available programs that allow you to view 'greyscale' GROBs.
They are:
  • GREYSCAL.ZIP Allows as many shades as you can stand, but the pictures have to be 131x64.
  • SCROLL4C.ZIP Allows only four shades but the picture can be any size.
Both of these (as well as lots of other stuff) are also available on:

Joe Horn's Goodies Disk 10 which is available on HP's Goodies Disk Archive.

Back to Ben's Homepage.