HP97 The journey begins

[teenix]

Hi all,

I've added a new feature to the HP67 CPU module, from an idea from Pauli, that featured in an old issue of HP65 notes.

The idea was to program the cards to show Non Normal Numbers on the calculator display which would be useful for "on screen" messages for programs and games.

I've enabled the code in the HP emulator to test the theory of this and it seems to work ok. (Haven't uploaded it yet)

These are the characters that can be displayed in any order up to 11 characters per display.

0 E c r
1 F d s
2 G f t
3 H g u
4 I h y
5 J i =
6 L j ?
7 O l _
8 P n -
9 S o [spc]
A U p
C b q

I created a small editor where you can type in up to 50 messages which can be accessed by the 67 when a program is running.

To make this work, I used one of the non useable program codes to signal the 67 to display a message when it executes.

To enable a message when programming, you first need to key in the message number which has to be in reverse. Eg Message #2 is entered as [2] [0], #39 as [9][3]. This is because the calculator will normalize [0][2] to just [2] in the C Register and the leading zero is lost.

After the message number has been entered, key in [h] [A]. This is an unused program key combination but if executed normally will do a GSB A.

However, this now executes as a "Message Execute" program token.
If this program entry is viewed on screen it will be displayed as 35 11 which is [h] [A].

Pretty Cool :-)

When the program runs and it encounters this token, the value is substituted with R/S and stops the program. When the program has stopped and all the internal "stuff" is done by the HP microcode, the message will be displayed. None of the HP Microcode was changed, it is still original.

An example is using the text editor to create "HELLO HP67" as Message #00.

The program key sequence to display this message is

[0]
[0]
[h][A]

The result is shown from the attached emulator 67 image.

Now that it works for the emulator, I will include it for the new 67 CPU module.


Edit: New emulator download available from teenix.org


cheers

Tony