HP97 The journey begins

[teenix]

Hi all,

While waiting for the new circuit boards (which should be here this afternoon), I have been playing with the 19C functionality.

By experimenting with the emulator, I have managed to add an extra 45 RAM registers and an extra 294 program steps. This system works similar to the HP-95C where you can have programs that operate in partitions. From the 19C's point of view, nothing has changed, it still works exactly the same as the original.

To accommodate this, I added 6 new key functions. These can be executed directly from the keyboard and can be added to a program and executed during program execution.

Because the 19C cannot accommodate these functions, because all keys are in use, I changed the way the [f] key works.

The 6 functions are:

Code:


  [f][f][0] CLRR  Clear secondary RAM or Program registers
  [f][f][1] RAND  Puts a random number in X, where 0 < X < 1
  [f][f][2] GTOP  GTO a program LBL Page 0 - 3
  [f][f][3] GSBP  GSB a program LBL Page 0 - 3
  [f][f][4] RPGE  Swap RAM or PGM pages - (similar to HP-67 P<>R key)
  [f][f][5] CONR  Place a stored constant into X, Constant Storage locations 0 - 9

Like the HP-95C you can run a program and GTO or GSB to more program data in a different partition.

A key entry example for GTO LBL5 in PGM Bank 2 would be:

Code:


  2
  5
  [f][f][2]

The PGM banks will be swapped, and the HP Microcode will search from Top of Program to find LBL 5, and the program would continue.
GSB works the same, and a RTN will jump back to the calling page.

If you want to swap RAM to Bank 2 in RUN Mode, press:

Code:


2
[f][f][4]

Only RAM memory $01 - $0F changes.
$00 can be used for the I pointer, so it stays as is

I might make an addition to [f][f][4] so that if you key in:

Code:


8 or 9
[f][f][4]

The RAM/PGM page can then be selected by the I register contents


If you want to write or edit a program in Bank 3, in RUN Mode press:

Code:


7
[f][f][4]

To recall constant[6] into X, press:

Code:


6
[f][f][5]

It all seems to work ok in practice, so I will recode it to run in the 19C CPU board.

cheers

Tony