Panasonic HHC ROM 'capules'

[Jeff_Birt]

Greetings,

I have a Panasonic HHC (RL-H1400) on the bench to be fitted with a new battery pack. Seems to work other than the old NiCad pack being well past its 'best by' date. In doing some reading lst night I found that you can't create SnapFORTH programs without the SnapFORTH 'ROM capsule'. (But you can run them without it.)

The 'ROM capsule' is one of the odd EPROM sockets that Molex came out with in the 1980s. The TRS-80 M100 used a similar socket for option ROMs. The Panasonic HHC variety is wired for standard EPROM pinouts but upside down. Looking at pictures of the capsules indeed it is just an upside-down EPROM wrapped around the Molex carrier.

Has anyone created images of any of these capsules. I have had no luck finding them on the web.

One really odd thing about the Panasonic HHC is that it uses an NMOS 6502 processor (Rockwell), in a 40-pin DIP. It looks like there were trying to come up with something quickly using COTS parts.

[Paul Berger (Canada)]

Any of the EPROM modules I have seen for the HHC have been the Motorola 68764 EPROM that is a 24 pin 8K EPROM different from the more common 28 pin 2764. The compiler "capsules" use a special 16K ROM that uses what would be the -E pin of a 68764 as an extra address pin. This is possible because the ROM capsules are bank selected by controlling power to the capsule instead of using a select signal. I am not aware of any replacement for this very odd ROM module, making duplicating these capsules difficult. Some time ago I purchased one of the kits that GE put together for programming some of their industrial radios and they got around this by having their program ROMs in a plug in module that contains industry standard ROMs. I have not dug into it far enough to figure out how they managed selection of ROMs but there is a signal on the HHC bus to enable external ROM when none of the internal capsules are selected .

Paul.

[Jeff_Birt]

(01-04-2023 06:56 PM)Paul Berger (Canada) Wrote:  I am not aware of any replacement for this very odd ROM module, making duplicating these capsules difficult.

Thanks for the heads up on the EPROM used.

The TRS-80 Model 100 uses another variant of these goofy Molex sockets and some clever folks designed a 3D printed carrier and PCB layout with castellated PCB edges as contacts. This would be a good jumping off point to design a PCB and carrier. You can also get the 68674 for ~$1 on eBay as well.

http://tandy.wiki/Teeprom

I have a saved search on eBay so hopefully some of the capsules will show up.

[Didier Lachieze]

You should ask on the French Mysilicium forum. Some people there have dumped modules and have also build modules with EPROMs.

[Jeff_Birt]

(01-04-2023 07:57 PM)Didier Lachieze Wrote:  You should ask on the French Mysilicium forum. Some people there have dumped modules and have also build modules with EPROMs.

Thank you. My searches had not turned up any posts on the Silicium forum but searching the forum directly revealed some people had been dumping them in the past. I have now asked there as well.

[Steve Simpkin]

For reference, here is more information on this model including internal photos.
http://datamath.org/Related/Panasonic/RL-H1400.htm

Here is an example of a ROM capsule (MS BASIC).
   

[Paul Berger (Canada)]

(01-04-2023 07:25 PM)Jeff_Birt Wrote:  

(01-04-2023 06:56 PM)Paul Berger (Canada) Wrote:  I am not aware of any replacement for this very odd ROM module, making duplicating these capsules difficult.

Thanks for the heads up on the EPROM used.

The TRS-80 Model 100 uses another variant of these goofy Molex sockets and some clever folks designed a 3D printed carrier and PCB layout with castellated PCB edges as contacts. This would be a good jumping off point to design a PCB and carrier. You can also get the 68674 for ~$1 on eBay as well.

http://tandy.wiki/Teeprom

I have a saved search on eBay so hopefully some of the capsules will show up.

I was referring to duplicating things like the compiler modules that do not use the 68674 8K EPROM, but rather use an oddball 16K ROM that replaces the chip select line with another address line to squeeze 16K into a 24 pin chip 14 Address, 8 data, and 2 power = 24 pins. All commercial 16K EPROMs and ROMs I know of are in 28 pin packages. I would agree may be possible to make a replacement using more modern components.

[Jeff_Birt]

(01-04-2023 09:34 PM)Paul Berger (Canada) Wrote:  I would agree may be possible to make a replacement using more modern components.

Yes, I agree. That is what I was meaning.

A nice chap on the Silicium forum did have a bunch of ROMs saved so now I just need to build such a carrier or get the correct EPROM. As you say though the larger ROMs will require more effort and some modern parts.

On another note, I built a new battery pack for it today and found that it is Y2K compliant. It even figured out it was a Thursday all by itself.

   

[brouhaha]

(01-03-2023 05:19 PM)Jeff_Birt Wrote:  you can't create SnapFORTH programs without the SnapFORTH 'ROM capsule'. (But you can run them without it.)

The SnapFORTH development ROM was 16KiB and wouldn't fit in a capsule. It was an expansion box, about the same size as e.g. the RS-232 expansion box, but without an I/O connector. Inside there are EPROMs and logic for bank-switching.

Technically a capsule port could address 16KiB, but the capsules are 24-pin, and there was no 16KiB 24-pin EPROM. Even the 8KiB 24-pin EPROMs were and are relatively uncommon; normal 8KiB EPROMs (Intel 2764 and equivalent) are 28-pin. The only 24-pin 8KiB EPROMs were the Motorola MC68764 and MC68766.

If one somehow made a 16KiB capsule, I'm not sure whether SnapFORTH would run from it, or whether it requires some of the logic in the expansion box.

[qoute]
Has anyone created images of any of these capsules. I have had no luck finding them on the web.
[/quote]

There are images around. I have some but I'd have to do some digging to find them.

One thing to be aware of is that the commonly available images of the Microsoft BASIC capsule have a corrupted byte. I posted about that on cctalk some years back with details on which byte, and what the likely effects were:

https://marc.info/?l=classiccmp&m=120657197412183&w=2

I spent some time reverse-engineering the HHC "intrinsic" (internal) ROM and some of the plug-in ROMs. I put the work I'd done on the intrinsic ROM and the SnapFORTH ROM on github:

https://github.com/brouhaha/hhc

Quote:One really odd thing about the Panasonic HHC is that it uses an NMOS 6502 processor (Rockwell), in a 40-pin DIP. It looks like there were trying to come up with something quickly using COTS parts.

It may seem odd, but it was the only practical solution when the HHC was developed. The HHC was introduced in fall 1980 in Japan (early 1981 worldwide), and development was started in 1978. There was no suitable CMOS microprocessor at the time it was developed; the 65C02 wasn't introduced until 1983. The only commercially available single-chip CMOS microprocessors in existence in 1978 were the Intersil IM6100 (PDP-8 12-bit instruction set) and RCA "COSMAC" CDP1802, both of which were much slower than the NMOS 6502.

[Jeff_Birt]

(01-06-2023 06:55 AM)brouhaha Wrote:  The SnapFORTH development ROM was 16KiB and wouldn't fit in a capsule. It was an expansion box, about the same size as e.g. the RS-232 expansion box, but without an I/O connector. Inside there are EPROMs and logic for bank-switching.

Looking at the HHC documentation about SnapFORTH they mention the SnapFORTH capsule multiple times. The only sort of memory expansion I can find that plugged into the system bus is a 16K RAM expansion. I also see that an EPROM burner is mentioned. Looking at the ROM images I got from the Silicium forum it seems that both SnapBASIC and SnapFORTH were 16K capsules. Perhaps they used the EPROM box until they could get the custom 16K, 24-pin ROMs made?

EDIT: Reading some other Panasonic HHC related messages from the linked archive there was a reference to a 3rd party EPROM box (bottom mounted) and a reference to a side mounted SnapFORTH compiler add on.

Thanks for the tip on the SnapBASIC image being corrupted this line in that message:

"The HHC inverts address line A12 to the ROMs, so the two halves of the EPROM are logically swapped." explains the file naming convention in the ROM files I received, i.e. the use of 'swapped' in some file names.

[brouhaha]

Jeff_Birt Wrote:Looking at the HHC documentation about SnapFORTH they mention the SnapFORTH capsule multiple times.

Maybe they called it a capsule even though it was a box. I made that mistake in some of my own notes about it.

Quote:The only sort of memory expansion I can find that plugged into the system bus is a 16K RAM expansion. I also see that an EPROM burner is mentioned.

The SnapFORTH box hardware was AFAIK special for that, and doesn't match any other sold option.

Quote: Looking at the ROM images I got from the Silicium forum it seems that both SnapBASIC and SnapFORTH were 16K capsules.

The SnapBASIC I have is only 8K. (EDIT) I double checked, and I was mistaken. SnapBASIC is 16K.

Quote:
Perhaps they used the EPROM box until they could get the custom 16K, 24-pin ROMs made?

AFAIK, there were never any 16K capsules fitting in the 24-pin capsule slots, even though it was sort of theoretically possible.

Quote:EDIT: Reading some other Panasonic HHC related messages from the linked archive there was a reference to a 3rd party EPROM box (bottom mounted) and a reference to a side mounted SnapFORTH compiler add on.

The side-mounted device what I've been talking about. That's the only native SnapFORTH development environment, though a cross development for the Apple II also existed.

Quote:Thanks for the tip on the SnapBASIC image being corrupted this line in that message:

No, it's Microsoft BASIC that has corrupted dumps. SnapBASIC is fine, orat least there's no obvious evidence of a problem.

AFAICT, the Microsot BASIC capsule outsold the SnapBASIC capsule by about a zillion to one. SnapBASIC was better integrated to the system, and could share resources better, vs. Microsoft BASIC just sucking up all the RAM and not cooperating with anything. However, Microsoft BASIC was much faster, and was what people were more familiar with, being largely identical to Microsoft BASIC on other platforms.

[brouhaha]

I had done a little more work on the HHC SnapFORTH ROM reverse-engineering after thee last think I pushed to github in August 2018, so I just pushed that, along with the little bit of work I'd done at that time to start reverse-engineering the SnapBASIC ROM.

https://github.com/brouhaha/hhc

[Paul Berger (Canada)]

(01-06-2023 06:55 AM)brouhaha Wrote:  

(01-03-2023 05:19 PM)Jeff_Birt Wrote:  you can't create SnapFORTH programs without the SnapFORTH 'ROM capsule'. (But you can run them without it.)

The SnapFORTH development ROM was 16KiB and wouldn't fit in a capsule. It was an expansion box, about the same size as e.g. the RS-232 expansion box, but without an I/O connector. Inside there are EPROMs and logic for bank-switching.

The Snapforth was very definitely released as a capsule I have one along with the Snap BASIC and Microsoft BASIC. The HHC bank selects the capsule ROMs by switching the power pin and for the 16K capsules they use what would normally be the -E pin as an address line. One thing that it occurs to me that they may have done was mounted the dies for a "normal" 16K ROM in a 24 pin package and internally wired bonded the enable pin so that it would always be enabled when the powered up.

Paul.

[brouhaha]

(01-08-2023 05:39 PM)Paul Berger (Canada) Wrote:  The Snapforth was very definitely released as a capsule I have one along with the Snap BASIC

Interesting! A friend worked for Cyber Diagnostics Inc. in the Denver area in the late 1970s and early 1980s. They made pulmonary function testing equipment, such as lung capacity measurement devices, and were developing some product(s) using the HHC. They were only able to get SnapFORTH in box form, and the cross-development software for the Apple II, which unfortunately no one saved. Maybe the SnapFORTH and SnapBASIC capsules came later.

It would be interesting to see the IC markings, but the capsules I've seen have an opaque label over the top of the chip.

It's possible that there may have been a masked ROM vendor that offered a 16KiB 24-pin chip, though I never heard of it back in the day. Probably it wouldn't have been terribly expensive to have a masked ROM vendor do a custom bonded 24-pin part.

[BobVA]

(01-08-2023 10:18 PM)brouhaha Wrote:  Interesting! A friend worked for Cyber Diagnostics Inc. in the Denver area in the late 1970s and early 1980s. They made pulmonary function testing equipment, such as lung capacity measurement devices, and were developing some product(s) using the HHC...

I wonder if Panasonic targeted the medical market? A friend of mine worked on an HHC package to analyze data from a cardiac output monitor around that time.

[Paul Berger (Canada)]

Its too bad about the Apple II development system a few years ago I bought a lot of HHC stuff and among that lot there was a copy of a document "A Programmer's Manual for the Hand-Held Computer' written by Friends Amis and the Apple II development system is mentioned in their I had scanned it some time ago for another person interested in the HHC and it is still floating around n my Google Drive https://drive.google.com/drive/folders/1...sp=sharing.

I also bought one of the kits that GE put together for programming industrial radios. It is an 8K HHC with printer and RS-232 adapters as well as two custom GE modules one is called Data I/O module that has a DB-9 connector and a plug in adapter that appears to be for programming EEPROMs. The more interesting one is the "Program Storage Module" which has sockets for 8 27C128 EPROMs, imagine 128K of storage! All of this packed in a sturdy fitted suitcase.

I have one SnapBASIC module that has a pin rotted off it so I lifted the label on the top and found:
AMI 8306RE
11677A (the first two character could be II)
SBASIC Korea

Paul.

[Paul Berger (Canada)]

(01-08-2023 11:55 PM)BobVA Wrote:  

(01-08-2023 10:18 PM)brouhaha Wrote:  Interesting! A friend worked for Cyber Diagnostics Inc. in the Denver area in the late 1970s and early 1980s. They made pulmonary function testing equipment, such as lung capacity measurement devices, and were developing some product(s) using the HHC...

I wonder if Panasonic targeted the medical market? A friend of mine worked on an HHC package to analyze data from a cardiac output monitor around that time.

It seems they where widely used by insurance salesmen too that would seem to be the source of most that turned up on eBay.

Paul.

[Jeff_Birt]

(01-09-2023 12:35 AM)Paul Berger (Canada) Wrote:  Its too bad about the Apple II development system a few years ago I bought a lot of HHC stuff and among that lot there was a copy of a document "A Programmer's Manual for the Hand-Held Computer' written by Friends Amis and the Apple II development system is mentioned in their I had scanned it some time ago for another person interested in the HHC and it is still floating around n my Google Drive https://drive.google.com/drive/folders/1...sp=sharing.

Thanks for the documents. The Technical Information of Hardware is the only such document I seen so far from Panasonic. The only other tech info I had found were hand drawn, reverse engineered, schematics.

[brouhaha]

(01-09-2023 12:35 AM)Paul Berger (Canada) Wrote:  Its too bad about the Apple II development system a few years ago I bought a lot of HHC stuff and among that lot there was a copy of a document "A Programmer's Manual for the Hand-Held Computer' written by Friends Amis and the Apple II development system is mentioned in their I had scanned it some time ago for another person interested in the HHC and it is still floating around n my Google Drive

Wow, those documents are great! Thanks for sharing them. They would have saved me a huge amount of time back when I was trying to reverse-engineer the HHC. Even now, if I can find time to work on it, I can use the Programmer's Manual to update my sources for a lot of stuff I hadn't yet figured out.

Quote:I have one SnapBASIC module that has a pin rotted off it so I lifted the label on the top and found:
AMI 8306RE
11677A (the first two character could be II)
SBASIC Korea

AMI was a big player in masked ROM (and made PMOS chips for HP calculators). The 8306 is the date code (sixth week of 1983), and 11677A is probably the mask code number AMI assigned.

I see mention in the manuals that 16K ROMs are "slow ROMs" and have to be marked as such. I'll have to check whether the image I have is so marked. Since it was in an separate EPROM box, it rpobalby could have run fast.

[Jeff_Birt]

I was wondering if anyone, in the USA, who had an original ROM capsule would be willing to loan it to me? A friend of mine developed these 3D printable ROM./PCB carriers that fit the Molex sockets in the TRS-80 model 100 et. al. There is a link on the page below to the Github repo for the project.

http://tandy.wiki/Molex78802_Module

He was nice enough to offer to develop carriers for this Molex socket variation. I do not have an original ROM carrier to measure up though, so we are starting from the design he has already done for the Molex 78802 socket (which he found datasheets for) and measurements I am making of the socket in my HHC. Being able to measure up a real module would be a big help. Of course, the new models will be added to his repo and open for all to use.