HP 9836 Boot ROMs #9836


Martin Hepperle
 

I recently obtained an early (1981) 9836A with the 2.0 Boot ROMs.
It has the first CPL board with 64 KB RAM and no MMU (no "U" model).

I am wondering whether it is possible to install later (e.g. 3.0) ROMs.
The ROMs are socketed, but in DIL-24 not in DIL 28.
The later ROMs have more startup messages (with inventory of installed boards etc.) and allow booting from external drives.

Currently, I boot BASIC 2.0 from a ROM board or 5.1 from disketrtes.

Martin


Paul Berger
 


On 2022-05-09 13:37, Martin Hepperle wrote:
I recently obtained an early (1981) 9836A with the 2.0 Boot ROMs.
It has the first CPL board with 64 KB RAM and no MMU (no "U" model).

I am wondering whether it is possible to install later (e.g. 3.0) ROMs.
The ROMs are socketed, but in DIL-24 not in DIL 28.
The later ROMs have more startup messages (with inventory of installed boards etc.) and allow booting from external drives.

Currently, I boot BASIC 2.0 from a ROM board or 5.1 from disketrtes.

Martin
_._,_._,_


What part number is your card?  I have a 09836-66510 with no MMU and a DIL 68000 processor (1820-2505) and at the opposite end of the board there are 4 28 pin sockets with ROMs in the sockets marked low odd and low even.  It looks the same as the board pictured at http://www.hpmuseum.net/images/09836-66510_9836Processor-RAM-31.jpg.  The ROMs on it are for BootROM 3.0. I tried  the BootROM 4.0 ROMs from a 09826-66517 68010 and MMU card and they would not work on the 09836-66510.

I see that there are some jumper positions along the bottom edge starting below the ROMs that appear to be related to the ROMs

Paul.


Martin Hepperle
 

Pauil,

the card is a 09826-66515. It only has two DIL-24 sockets besides the 68000 CPU.

In the CE handbook (pg. 3-1) I find it as the first board for the 9836, the next revision must have been the 66516.

For the 9826, it lists a 09826-66511 as the first board, so your ...10 board must be an earlier version than the CE handbook (which is dated Julöy 1983, so about 2 years after these machines were introduced).

Martin


Paul Berger
 

Martin,

Looking at the Tony Duell schematics for 9826/9836 which include the 09826-66515, it would seem it would be possible however it would take some modification of the CPU board.  The ROMs on the 66515 card are 8K byte ROMs while the newer cards use 32K byte ROMs, so what you would need is an adapter to support the 28 pin devices and bring out  A14 and A15 to this adapter.the -ROMCS signal appears to be valid for the first 64K words of the address space.  There are images posted on hpmuseum.net but it is not clear what level of bootrom they are for.

Paul.

Paul.

On 2022-05-10 03:54, Martin Hepperle wrote:
Pauil,

the card is a 09826-66515. It only has two DIL-24 sockets besides the 68000 CPU.

In the CE handbook (pg. 3-1) I find it as the first board for the 9836, the next revision must have been the 66516.

For the 9826, it lists a 09826-66511 as the first board, so your ...10 board must be an earlier version than the CE handbook (which is dated Julöy 1983, so about 2 years after these machines were introduced).

Martin


 

Hi Martin,

 

I’ve a spare 09826-66516 board lying around here.

If you’re interested let me know.

 

-Rik

 

Van: VintHPcom@groups.io <VintHPcom@groups.io> Namens Martin Hepperle
Verzonden: dinsdag 10 mei 2022 08:54
Aan: VintHPcom@groups.io
Onderwerp: Re: [VintHPcom] HP 9836 Boot ROMs #9836

 

Pauil,

the card is a 09826-66515. It only has two DIL-24 sockets besides the 68000 CPU.

In the CE handbook (pg. 3-1) I find it as the first board for the 9836, the next revision must have been the 66516.

For the 9826, it lists a 09826-66511 as the first board, so your ...10 board must be an earlier version than the CE handbook (which is dated Julöy 1983, so about 2 years after these machines were introduced).

Martin


Martin Hepperle
 


Thank you for the ideas, Paul,

I will have a look at Tonys fabulous schematics (I already used it to fix the PSU) maybe it is possible to add a few wires without changing the board itself.
On the other hand my board does not have the ID PROM (it was added in the next revision) and if the boot ROMs test for this, they might complain with an error message.
First I should image the 2.0 boot ROMs just for preservation.

Another option would be to replace the 2.0 BASIC ROM with a more recent board, maybe from Dominique Berget or replace the ROMs on the DIO board for something like 3.0 BASIC if I can get a copy of that.
On most of my other HP 9000 I use BASIC 5.1.

Martin

Just for completeness: here is a picture of the 66515 board. The two ROMs are different types.


... and ... not only the Commodore 64 can serve as a bread box... but this one has better shielding.