HP 86/87 Matrix Rom Manual

[Michael Fehlhammer]

Obviously the HP 86/87 version of the matrix rom is essentially different from the HP 85 version, as it is composed of two ROM chips ( matrix 1 and 2; just one matrix ROM for the HP 85).
Therefore I assume that the HP 86/87 matrix ROM is more powerful and has more BASIC keywords than the HP 85 version.
On the internet only the HP 85 matrix ROM manual is available ( e.g. at series80.org, or hpmuseum.net ).
Does anyone know details about the additional functions in the HP 86/87 ROM, or even better, can anyone point me to a source for the manual?

[Raymond Del Tondo]

Hi Michael,

the HPMuseum DVD contains a "Series 80 Matrix ROM Manual", maybe this could be of help?

Cheers

[Michael Fehlhammer]

Thanks Ray,
but unfortunately this manual also covers the HP 85 version of the matrix ROM ( only ).
Perhaps there is kind of an addendum for the additional functions in the HP 86/87 matrix 2 ROM, or I would need the HP 86/87 manual version - or my assumption was wrong that there are additional functions. But what else should be included in the second ROM ?

[Marcus von Cube]

You can download the ROM images from seris80.org. I did out of curiosity. The keywords start at 78h in the 85 ROM and at 82h in the first 87 ROM. I tried to extract the strings from both. If I'm not mistaken the lists look fairly identical.

[Raymond Del Tondo]

So maybe the 87 version could contain some bug fixes and/or adaptions for the wide-screen CRT of the HP-87, which would possibly explain the need for a 2nd ROM chip. Tony?

[Michael Fehlhammer]

(03-22-2014 09:58 PM)Marcus von Cube Wrote:  You can download the ROM images from seris80.org. I did out of curiosity. The keywords start at 78h in the 85 ROM and at 82h in the first 87 ROM. I tried to extract the strings from both. If I'm not mistaken the lists look fairly identical.

Thank you for checking that, Marcus!
Bug fixes and wide screen support - yes, Raymond, maybe that is the secret of the second ROM.
Anyone out there who has got the HP 86/87 Matrix ROM manual and can tell exactly?

[patrice]

As far as I remember.
There is a set of ROMs for HP 83 and 85 and a set of ROMs for HP 85B, 86 and 87.
The main reason of those 2 sets of ROMs is that the 83/85 have 16 bits memory address space and the CPU can access everywhere.
Contrary, the 85B/86/87 have 24 bits memory address space and access of memory above the first 64KB is done with 2 special pointers.
the difference between direct memory access and pointer memory access takes a small amount of space in CPU code to do the same thing. That small amount over a ROM can be enough to make that the code don't fit in the 8KB of the ROM, thus needing 2 ROMs.

[Michael Fehlhammer]

(03-23-2014 06:54 PM)patrice Wrote:  That small amount over a ROM can be enough to make that the code don't fit in the 8KB of the ROM, thus needing 2 ROMs.

Sounds logical. In combination with Marcus' finding ( no additional keywords in the 86/87 version )
it is unlikely that there are any differences concerning functionality, so the HP 85 Matrix ROM manual will suffice. Thank you!