Powering up H8 after over 30 years - Looking for advice on steps
eric.mack
Norberto Collado
If your H8 is using the gold header on the backplane, just power-up the H8 and it should work. My H8 power-up after I took it from storage.
If your H8 backplane is using the tin-plated headers, then all the H8bboards will need to be reseated.
Norberto
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Lee Hart
> 1. Open H8 and photograph contents, as-is.
>
> 2. Remove cards, noting their position, make and model. Photograph each
> and set aside on anti-static mat
>
> 3. Unplug motherboard from power supply
>
> 4. General inspection and photograph
>
> 5. Power up and test power supply voltages, listen for pop and watch for
> magic smoke
>
> 6. If all is well, power off, connect PS to motherboard and repeat step #5
>
> 7. if all is well, power off and install CPU and Memory card and repeat
> step #5
>
> How do those steps look?
with no cards installed. The voltage on the capacitors will be at its
worst-case maximum, when they are the least able to withstand it.
If something is going to "go", it will be some capacitor.
--
There is a computer disease that anybody who works with computers knows
about. It's very serious, and interferes completely with your work. The
trouble with computers is that you 'play' with them! (Richard Feynman)
--
Lee Hart, 814 8th Ave N, Sartell MN 56377, www.sunrise-ev.com
Glenn Roberts
If you have the Z80 board and you had it configured with the H37 (soft-sectored) disk controller then you’ll need both boards plus a RAM board to power up and have a functional front panel. There is a ribbon cable that connects them. If you run without the H37 board there must be a 74LS148 in the socket on the Z80 board.
In dealing with getting old H8’s running the most common problem I’ve seen is bad RAM boards, especially dynamic RAM. System may show Power and Run LEDs lit but not Monitor. I have several 64K static RAM boards from an SEBHC group purchase some time ago (Les Bird design?) and they’re extremely reliable and have come in handy for eliminating memory board issues.
Sent from my iPad
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Glenn Roberts
I’ve also seen the front panel 7-segment LEDs fail but replacements are easily found on eBay (common cathode as I recall?) modern ones are much brighter than the originals. Take care removing these as the pins are fragile.
eric.mack
H8 Chassis S/N 03815 – Assembled by a much younger me and used for 8-10 years without issue. In fact I launched a few businesses using this computer.
.JPG?part=0.1&view=1)
Board Inventory
Backplane board uses TIN pins (I have DEOXIUT but have not used anything yet, pending advice)
HA8-6 Z80 CPU Board
DG 64K Memory Board
?? Controller (Suspect H17 Floppy)
Z37 - Z67 Controller Board
H8-4 Multi-Port Serial Board
I removed all boards, except for the Z-80 CPU & 46K RAM Board.
(This meant that I had to unplug the ribbon cable between Z37/Z67 Controller and the CPU Board.)
Power Up Steps I used (with ONLY CPU & RAM Installed)
First time, I powered up, I heard a beep and all 7 Segment displays flickered on and off
I powered off and reseated the CPU & Memory board
Powered up, beep and the top and bottom two LEDs are on. NOTHING on 7 Segment Displays
I seem to recall that I upgraded the front panel to HEX. (Perhaps the front panel buttons will confirm this?)
The only buttons I remember after 35 years was to press the lower left and right buttons on the keyboard, which I think is a reset.
Doing that produced the following results, which I can reproduce:
LED’s From Top to bottom
ION = ON (CPU is accepting Interrupts)
MON=OFF (Indicates if I have control from front panel) *
RUN = ON (Indicates that the CPU is in a RUN Condition)
PWR=ON (Indicates that +5 Volts is present at front panel)
* I think I remember that I purchased some kind of boot ROM, perhaps with the CPU Board? So that the computer would autoboot – I do not rec all if that was true or I thought it was true. How to tell?
I powered off for closer inspection
MYSTERY WIRE: On HA8-6 Z80 CPU Board, there is a 5 pin connector P201 and pin 1 (black wire, 4” long) is not connected to anything. It was not touching anything either. I taped it until I could investigate)
INVESTIGATION OF P201 CABLE from HA8-6 Z80 CPU
Front Panel Schematic shows a ribbon cable with a plug (that goes to P201) and the wired ends of that cable are soldered to various places on the back of the front panel – all EXCEPT the 4” black wire which is not connected to anything. Strange?
Lower right corner of the HA8-6 AZ80 CPU Schematic shows that P201-1 goes to ground – BUT WHERE? Should I solder it to the GND on the front panel? The length of the black wire would suggest so.
So, where I am at now: I power up, I have the LED’s as shown and that is it. I have careful photos of everything.
Any suggestions?
Eric
Norberto Collado
-------- Original Message --------
Subject: [sebhc] Re: Powering up H8 after over 30 years - Looking for
advice on steps
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eric.mack
OK, thanks to your help, I made great progress:
1. I soldered the 4" wire from CPU card to to the
ground of the back of the front panel board.
2. I reinstalled the Heath H37/H67 to the H8 back plane and reconnected the 16 pin ribbon cable back to the CPU. (I did not reinstall what I think is the H17 controller)
3. I powered up. Got a beep, all 4 LED's ON and 377 377 377 on the display.
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Norberto Collado
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eric.mack
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Glenn Roberts
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Glenn Roberts
Dave McGuire
> DG 64K Memory Board
Hey, I have one of these, and have searched fruitlessly for a manual
for it for a long time. It is labeled "DG 64D". Would you happen to
have a manual for yours?
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
eric.mack
eric.mack
Dave McGuire
Ahh, very cool. I never had the opportunity to see a Heathkit store,
but the stories I've heard about them make them seem rather magical.
Instead I'd wade through the latest catalog, page by page, drooling and
dreaming as a kid.
Later I went the S-100 route, and got an H-8 about fifteen years ago,
and a couple of H-89s more recently. Great stuff.
-Dave
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Dave McGuire
> OK, I know what it's like to be excited to find a resource -- just as I
> am for finding SEBHC. Here is a quick photo scan of the DG 64K Manual
> and the schematic.
>
> If you know of a better repository for these. please DO upload these so
> others can benefit.
>
> Best of success to you,
>
> Eric
>
> UPDATE Google won;t let me save these. Where is the best place to
> contribute these?
best. Would you mind sending me a copy offline, to this email address?
Thanks,
eric.mack
Dave McGuire
> I believe I have sent you the 2 files via direct email through Google.
> they do not reveal your email , so ;let me know.
Why would Google be hiding my address...? OH you're using this as a
web forum, not a mailing list, right? That'd do it. :-/ Sorry about
that, I didn't know.
> yes, the Heathkit stores were magical. The best part is the people -
> really smart and really friendly. From managers to techs, to the
> customers. It was a great time to be alive. Fortunately, the nearest
> store was only 40 minutes away.
eric.mack
Hi Norby, I followed the instructions you sent last night; however. I have been struggling to get the test to work. I believe the test is OK, but the system is looking for a Z67 which I do not have plugged in. .
I will start with the error I encountered and the described what I did, per your instructions. This way, if you see something right off you can stop reading and reply. :-)
I followed the test instructions to key in the test code and execute it. On page 8, where the test is executed I had a few differences, but that could be because I have a Z80 or 64K RAM or??
Page 8, second step: they say to press "." (REG) to display XXX.XXX.XXX. (I got 377.377._SP)
Page 8, third step: they say to press "6" (PC OUT) to display XXX.XXX._Pc. (I got 377.377._1y)
Page 8, fourth step: they say to press "/" (ALTER/RST) to display XXX.XXX._Pc. (I got 377.377._1y) and scanning dots
Page 8, fifth step: they say to enter "040100" to display 040 100 _Pc (I got 040 100 _Pc, so that is good!)
Page 8, sixth step: they say to press "/" (ALTER/RST) to display 040 100 _Pc (I got "Pri H67"
Page 8, seventh step: they say to press "4" (GO) to display success message (I got "Error H67")
OK, now you see the error.
Here is what I did, in response to your instructions
- Removed H17 Card from the system leaving the H37/H67 card in place and connected to the CPU
- Changed the Z80 Board switch settings (all were originally OFF) to have Switch 1 =ON and all others =OFF
- If I understand the docs, this tells the CPU to expect a Z67 at port 174Q, correct?
- So, since the Z80 Switch 4 is OFF, the primary boot will be 174Q which is the Z67, correct?
- I then examined the WH-8-37 Board to set switch 1 & 4=ON and leave the rest OFF
- Switch 1=ON assigns the Z67 Interface to 174Q
- Switch 4=ON assigns the Primary boot to Port 170Q (Which would be my future floppy?, correct?)
- I powered up and entered the self-test, which did not work, as outlined above. I tried 3 times; same result.
- Next, I decided to change the WH-8-37 Board to set switch 1 & 4=ON and leave the rest OFF
- Switch 1=ON assigns the Z67 Interface to 174Q
- Switch 4=OFF which assigns the Primary boot to Port 174Q (Which would be the Z67, correct?)
- I also verified that the jumpers are set to defaults according to Page 19 of the WH-8-37 Manual
- I powered up and entered the self-test, which did not work, as outlined above. Same error message.
So, I suspect there is a step or device missing. I'm stumped.
What do you advise?
Eric
eric.mack
On Sunday, September 15, 2019 at 11:40:06 PM UTC-7, Norby wrote:
To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/b09f48c6-782a-440f-9950-42812a3d0979%40googlegroups.com.
Norberto Collado
Just setup the Z80 switch and H37/H67 as I stated.
Please send me your address to send you a bootable floppy 3.5” to boot from your H37 board.
Thanks,
Norberto
4. Next I guessed. :-). I looked at the labels and noted that the 0, 1,2 buttons looked boot related (and my vague memory).
I pressed 1 and the display said "Pri H17"
I pressed CANCEL and then pressed 2 and the display said "sEC H37"
I reset and pressed 0 and the display said "dEU" - No idea what that is.
OK, so I assume those are all positive signs.I no longer have an H17 - must have sold it 25 years ago. I do have some drives from either H8 or H89. Some hard some soft sectors. I have some floppies from 35 years ago. No idea what might be readable after 35 years in a hot garage.
I have not connected H19 monitor or printer -- assuming those won't do anything until I can boot an OS.
What do you suggest I do next?
Thank you!
Eric
On Sunday, September 15, 2019 at 10:18:19 PM UTC-7, Norby wrote:
To power-up properly you will need to connect the Heath H37/H67 to the H8 backplane and connect the 16 pin ribbon cable back to the CPU as shown on your picture.
Pin 1 of the 5 pin connector is ground. Just solder it to the ground of the back of the front panel board. See attached picture.
Nice looking system.
Thanks,
Norberto
-------- Original Message --------
Subject: [sebhc] Re: Powering up H8 after over 30 years - Looking for
advice on steps
From: "eric.mack" <Eric...@FasterAtWork.com>
Date: Sun, September 15, 2019 9:01 pm
To: SEBHC <se...@googlegroups.com>
OK, this evening I decided to unpack and inventory the H8 I built in my teens Brought back great memories.
I could use some help getting this running. Here's a summary of the evening inspection.
H8 Chassis S/N 03815 – Assembled by a much younger me and used for 8-10 years without issue. In fact I launched a few businesses using this computer.
To unsubscribe from this group and stop receiving emails from it, send an email to sebhc+un...@googlegroups.com.
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Norberto Collado
I do not see anything attached to this email.
From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of "eric.mack" <Eric...@FasterAtWork.com>
Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Monday, September 16, 2019 at 9:10 PM
To: "se...@googlegroups.com" <se...@googlegroups.com>
Subject: Re: [sebhc] Re: Powering up H8 after over 30 years - Looking for advice on steps
OK, I know what it's like to be excited to find a resource -- just as I am for finding SEBHC. Here is a quick photo scan of the DG 64K Manual and the schematic.
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Glenn Roberts
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Lee Hart
Lee Hart
-----Original Message-----
From: "eric.mack" <Eric...@FasterAtWork.com>
>yes, the Heathkit stores were magical. The best part is the people - really
>smart and really friendly. From managers to techs, to the customers. It was
>a great time to be alive. Fortunately, the nearest store was only 40
>minutes away.
Excellence does not require perfection. -- Henry James
--
Lee A. Hart http://www.sunrise-ev.com
Dave McGuire
> Another cool thing was that my local HUG group met *at the Heath store*. It was the perfect place to meet friends, try new programs, and (of course) buy something new. :-)
Glenn Roberts
Eric: there are some subtleties associated with 3.5” drives. While you can get them to “look like” double-sided, double-density, 96TPI drives (~720K capacity) the cabling is slightly different than traditional 5.25” drives. I’m no expert but am being schooled by the experts on this list. I’ll send you some info off line…
- Glenn
4. Next I guessed. :-). I looked at the labels and noted that the 0, 1,2 buttons looked boot related (and my vague memory).
I pressed 1 and the display said "Pri H17"
I pressed CANCEL and then pressed 2 and the display said "sEC H37"
I reset and pressed 0 and the display said "dEU" - No idea what that is.
OK, so I assume those are all positive signs.I no longer have an H17 - must have sold it 25 years ago. I do have some drives from either H8 or H89. Some hard some soft sectors. I have some floppies from 35 years ago. No idea what might be readable after 35 years in a hot garage.
I have not connected H19 monitor or printer -- assuming those won't do anything until I can boot an OS.
What do you suggest I do next?
Thank you!
Eric
On Sunday, September 15, 2019 at 10:18:19 PM UTC-7, Norby wrote:
To power-up properly you will need to connect the Heath H37/H67 to the H8 backplane and connect the 16 pin ribbon cable back to the CPU as shown on your picture.
Pin 1 of the 5 pin connector is ground. Just solder it to the ground of the back of the front panel board. See attached picture.
Nice looking system.
Thanks,
Norberto
-------- Original Message --------
Subject: [sebhc] Re: Powering up H8 after over 30 years - Looking for
advice on steps
From: "eric.mack" <Eric...@FasterAtWork.com>
Date: Sun, September 15, 2019 9:01 pm
To: SEBHC <se...@googlegroups.com>
OK, this evening I decided to unpack and inventory the H8 I built in my teens Brought back great memories.
I could use some help getting this running. Here's a summary of the evening inspection.
H8 Chassis S/N 03815 – Assembled by a much younger me and used for 8-10 years without issue. In fact I launched a few businesses using this computer.
.JPG?part=0.0.1&view=1&authuser=0)
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Norberto Collado
Norby Wrote: "... It is easy to get a 3.5" floppy drive and boot HDOS or CP/M from it.
Yes that is correct! Just find a long floppy cable and connect a single 3.25” floppy drive (a good working floppy drive) to the H37 connector. By pressing the “SEC 2” key, it should boot from the floppy drive. If nothing happens (no LED activity on the floppy drive), then we will need to manually select the floppy # (0, 1, or 2).
See attached picture as a guideline.
I will send you two 3.5” diskettes to try out. HDOS 2.0 and CP/M with H67 support. If this works then you should be able to get some games to run on the H19 terminal. As my 5.25” floppy drives are old and not working properly, I decided to stay away from them for now.
If you see errors while booting CP/M from the 3.5” floppy drive, then implement the following change to the H37 controller connector. Solder a wire across pins 15 and 16 on the back of the H37 floppy connector. That should take care of the issue.
Hope this works,
Norberto
From: "se...@googlegroups.com" <se...@googlegroups.com> on behalf of "eric.mack" <Eric...@FasterAtWork.com>
Reply-To: "se...@googlegroups.com" <se...@googlegroups.com>
Date: Monday, September 16, 2019 at 10:11 PM
To: "se...@googlegroups.com" <se...@googlegroups.com>
4. Next I guessed. :-). I looked at the labels and noted that the 0, 1,2 buttons looked boot related (and my vague memory).
I pressed 1 and the display said "Pri H17"
I pressed CANCEL and then pressed 2 and the display said "sEC H37"
I reset and pressed 0 and the display said "dEU" - No idea what that is.
OK, so I assume those are all positive signs.I no longer have an H17 - must have sold it 25 years ago. I do have some drives from either H8 or H89. Some hard some soft sectors. I have some floppies from 35 years ago. No idea what might be readable after 35 years in a hot garage.
I have not connected H19 monitor or printer -- assuming those won't do anything until I can boot an OS.
What do you suggest I do next?
Thank you!
Eric
On Sunday, September 15, 2019 at 10:18:19 PM UTC-7, Norby wrote:
To power-up properly you will need to connect the Heath H37/H67 to the H8 backplane and connect the 16 pin ribbon cable back to the CPU as shown on your picture.
Pin 1 of the 5 pin connector is ground. Just solder it to the ground of the back of the front panel board. See attached picture.
Nice looking system.
Thanks,
Norberto
-------- Original Message --------
Subject: [sebhc] Re: Powering up H8 after over 30 years - Looking for
advice on steps
From: "eric.mack" <Eric...@FasterAtWork.com>
Date: Sun, September 15, 2019 9:01 pm
To: SEBHC <se...@googlegroups.com>
OK, this evening I decided to unpack and inventory the H8 I built in my teens Brought back great memories.
I could use some help getting this running. Here's a summary of the evening inspection.
H8 Chassis S/N 03815 – Assembled by a much younger me and used for 8-10 years without issue. In fact I launched a few businesses using this computer.
To unsubscribe from this group and stop receiving emails from it, send an email to sebhc+un...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/c392fa89-cc0f-4f9c-a6af-3962a31c0612%40googlegroups.com.
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eric.mack
MAKING PROGRESS!!
Glenn, thank you for your kind help on the floppy issue.
Tonight, Norberto sent me revised CPU and MEMORY diagnostics procedures that now work with my Z80 and 64K Ram (56K, Actually). Apparently the errors I had were due to the fact that the diagnostics in the manual assumed a 8080 CPU and 4 or 8K ram.
Following Norberto's changes, CPU and Memory tests passed. So I know my machine works.
Then, I saw your email and I followed your steps using on old 1.44mb 3.5” drive (no diskette) and I was able to get the drive to respond and spin up and seek using your boot sequence:
0 [boot]
3 [H37 device]
0 [Port 170)
1 [Unit 1]
Of course, I have no bootable 3.5” diskettes.
While waiting for Norberto to send me bootable 3.5” diskettes to test, I decided to go dig up my 5.25” floppy collection and some H8 era 5.25" drives.
I found all my original source disks, and other than being subjected to 35
years of hot/cold cycles, they are in clean mint condition. I have all the
stuff Heathkit sold, CPM and all the Microsoft languages and compilers. And, Wordstar! and DBASE 2 (I'm sure I have Supercalc too.). I also found boxes of never used 5.25" media, both hard and soft sector.
I have no idea if any of these are readable, but physically, they are beautiful, having been sealed airtight for 35 years.
I found some 5.25” DSDD diskettes that have “bootable CP/M” written on the label in handwriting that resembled a much younger me. 😊
I played with a combination of drives and diskettes with no success. Two drives spun up one did nothing. A few gave boot error on the H8 (I have no terminal plugged in yet)
Anyway, at least there is noise and a motor spins and no smoke.
In your experience, have you found 40 year old 5” drives still work? Are there tricks to reconnecting – I seem to remember we needed terminators. It’s been so many years…
In your experience have you found any of your orginal diskettes to be readable? I remember the doom and gloom discussions at HUG about how media was only going to last 7 years tops.
So, that is where I am at, so far.
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Glenn Roberts
Eric: Do you have any “PC” style floppy drives hanging around (5.25” “360K” drives, either full height or half height)? If not, these can be found on eBay or pulled out of any old PC hardware you might have around. It is very straightforward to get these working with the H37 if you have a cabinet/power supply to mount them. these will let you work with any of the soft sectored disks you have. You must have had such drives at one time (perhaps in an H77 cabinet?). Any idea where they are? – there’s a pretty good chance they’re still working. You’ll need the “360K” drives, not the newer “1.2M” ones, though the latter can be used to emulate the old 8” drives I’m told - other experts on this list can explain how to do that!
I have had reasonably good luck reading old disks. The soft sectored disks have been more successful for me, perhaps because when they were manufactured later in the evolution of floppy disks (early 80’s?) - maybe the industry had had some time to improve quality control and manufacturing? If you’ve got unopened (New Old Stock – “NOS”) soft sectored floppys you might have good luck and be able to format with them. some brands are terrible. My old Wabash and Memorex disks are worthless but the Verbatims are pretty reliable. NOS 5.25” soft-sectored diskettes are still available on the market.
As for your hard-sectored disks – you’d need to set up an H17 with 100K drives and put your H17 controller board in your computer. If you’re interested in this you could contact me off line – I think I have an H17 cabinet and I know I have some 100K drives but not sure what shape they’re in. there are specific steps needed to have the H17 and H37 drives co-exist in the same chassis (documented in the Heathkit doc’s of course!). If you do decide to experiment with H17 disks we have hole punches (Ken Owen knows more) which can add the 10 hard sectored holes to a soft-sectored disk. Then with a simple serial cable and a PC you can actually re-create any of the legacy 100K disks for your system.
The main problem with older disks, as I understand it, is that the oxide tends to come off, so you may only be able to read your old disks a few times before you notice reliability issues. You’ll also probably want to clean the disk drive heads often with some Q-tips and alcohol (or an old “cleaning disk” with alcohol on it, if you’re lucky enough to still have one of those!).
Personally, I see only three reasons to fool with old floppy drives: 1) to initially get a system up and running (as you are doing), 2,) to be able to read in and preserve/share old software and files from our legacy disks, and 3) to have the satisfaction of restoring and demonstrating the old hardware. In my opinion you will not want to depend on floppys for any real work, they’re just too unreliable! My own systems use Compact-Flash drives and Norberto’s Z67-IDE+ as the main system drives and USB sticks as the archival, backup and transfer mechanism (instead of floppys). I’ve also built a “jukebox” device driver and application that lets me keep up to 4,096 HDOS disk images online for instant mounting and use (haven’t figured this out for CP/M yet…)
It sounds like you may have some software that the group doesn’t have archival copies of. It would be great to read these and archive them before they’re forever lost to bit rot! David Troendle is also helping us scan and preserve the documentation for these.
Enough rambling for now… good luck and keep us apprised!
- Glenn
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eric.mack
Dave McGuire
> Glenn, thanks for the detailed explanation. I was using older drives,
> but now I realize that I had them plugged into the H37 and not the H17
> (Which Norberto had me unplug.) So much I need to remember about these
> H8's.
still there, it just needs to be refreshed, like DRAM. :)
> I have no plans to use floppies long-term. And I don't have any data to
> retrieve. So I only need them long enough to get started and to switch
> to CF or other storage media.
old, with usually pretty good results. We're demonstrating them for
visitors, which is a bit more important than having the ultimate in data
reliability (we can regenerate them any time if they fail) but they do
work pretty well.
Nearly all of the ones we use are 8", not 5.25", and they were made a
bit tougher (since they predate much of the "consumerization" of floppy
disks), but still, they do pretty well. These are primarily on DEC
PDP-11 systems.
> (I do have in my museum a short lives 2.5" floppy -- remember those?)
Glenn Roberts
Great! “360K” PC drives can also be used with the H17 but I think your best bet is to try them with your soft sectored controller (H37) – that is assuming you have some bootable 5.25” soft-sectored disks? Once you get Norberto’s 3.5” disks you can try those too of course – the 3.5” drives and disks tend to be much more reliable and fast. If you want to hook “360K” drives to your H17 controller card we can walk you through that -trick is in the jumpers and terminators.
The H17 and H37 cards can co-exist in the same chassis but you must disable the H67 interface to make that work – probably why Norberto suggested pulling out the H17 controller card…
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eric.mack
Glenn Roberts
Love the old twinkies. Reminds me of the movie Red2. They’re in a “safe house” from the 1980’s and Marvin bites into a 30-year old moon pie he finds in a drawer. Sarah gives him a strange look – “you’re eating that?!”. He answers “this is from before they had those ‘use by’ dates…” 😊
Google says “Jolt” was invented in ’85 so that wasn’t around in my early computing days – late nights at an ‘029 IBM keypunch!
From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of eric.mack
Sent: Wednesday, September 18, 2019 10:51 AM
To: SEBHC <se...@googlegroups.com>
Subject: Re: [sebhc] Re: Powering up H8 after over 30 years - Looking for advice on steps
That's encouraging, Dave. The museum is my own. See here http://www.ericmackonline.com/ICA/BLOGS/emonline.nsf/dx/eternaltwinkies
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Norberto Collado
I think the oxide that came out perhaps acted as sand paper destroying the heads. So I do not have anymore working 5.25" floppy drives. I did try buying some from eBay at a premium and they did not work. So that is why, I'm wired to use the 3.5" floppy drive going forward. Now USB and then in the near future use the network as my boot device.-------- Original Message --------
Subject: Re: [sebhc] Re: Powering up H8 after over 30 years - Looking
for advice on steps
From: "eric.mack" <Eric...@FasterAtWork.com>
Date: Wed, September 18, 2019 7:26 am
To: SEBHC <se...@googlegroups.com>
Glenn, thanks for the detailed explanation. I was using older drives, but now I realize that I had them plugged into the H37 and not the H17 (Which Norberto had me unplug.) So much I need to remember about these H8's.
Anyway, I will inventory the drives I have and label them so we can continue this discussion.I would be more than happy to contribute scans of documentation or disk images if what I have is not already in the group library. I'll make an inventory and post as a new thread. This way, perhaps you and the other archivists can chime in...I have no plans to use floppies long-term. And I don't have any data to retrieve. So I only need them long enough to get started and to switch to CF or other storage media. (I do have in my museum a short lives 2.5" floppy -- remember those?)Meanwhile, I'll print and review this thread.On Wednesday, September 18, 2019 at 5:59:39 AM UTC-7, Glenn wrote:
Eric: Do you have any “PC” style floppy drives hanging around (5.25” “360K” drives, either full height or half height)? If not, these can be found on eBay or pulled out of any old PC hardware you might have around. It is very straightforward to get these working with the H37 if you have a cabinet/power supply to mount them. these will let you work with any of the soft sectored disks you have. You must have had such drives at one time (perhaps in an H77 cabinet?). Any idea where they are? – there’s a pretty good chance they’re still working. You’ll need the “360K” drives, not the newer “1.2M” ones, though the latter can be used to emulate the old 8” drives I’m told - other experts on this list can explain how to do that!I have had reasonably good luck reading old disks. The soft sectored disks have been more successful for me, perhaps because when they were manufactured later in the evolution of floppy disks (early 80’s?) - maybe the industry had had some time to improve quality control and manufacturing? If you’ve got unopened (New Old Stock – “NOS”) soft sectored floppys you might have good luck and be able to format with them. some brands are terrible. My old Wabash and Memorex disks are worthless but the Verbatims are pretty reliable. NOS 5.25” soft-sectored diskettes are still available on the market.As for your hard-sectored disks – you’d need to set up an H17 with 100K drives and put your H17 controller board in your computer. If you’re interested in this you could contact me off line – I think I have an H17 cabinet and I know I have some 100K drives but not sure what shape they’re in. there are specific steps needed to have the H17 and H37 drives co-exist in the same chassis (documented in the Heathkit doc’s of course!). If you do decide to experiment with H17 disks we have hole punches (Ken Owen knows more) which can add the 10 hard sectored holes to a soft-sectored disk. Then with a simple serial cable and a PC you can actually re-create any of the legacy 100K disks for your system.The main problem with older disks, as I understand it, is that the oxide tends to come off, so you may only be able to read your old disks a few times before you notice reliability issues. You’ll also probably want to clean the disk drive heads often with some Q-tips and alcohol (or an old “cleaning disk” with alcohol on it, if you’re lucky enough to still have one of those!).Personally, I see only three reasons to fool with old floppy drives: 1) to initially get a system up and running (as you are doing), 2,) to be able to read in and preserve/share old software and files from our legacy disks, and 3) to have the satisfaction of restoring and demonstrating the old hardware. In my opinion you will not want to depend on floppys for any real work, they’re just too unreliable! My own systems use Compact-Flash drives and Norberto’s Z67-IDE+ as the main system drives and USB sticks as the archival, backup and transfer mechanism (instead of floppys). I’ve also built a “jukebox” device driver and application that lets me keep up to 4,096 HDOS disk images online for instant mounting and use (haven’t figured this out for CP/M yet…)It sounds like you may have some software that the group doesn’t have archival copies of. It would be great to read these and archive them before they’re forever lost to bit rot! David Troendle is also helping us scan and preserve the documentation for these.Enough rambling for now… good luck and keep us apprised!
- Glenn
From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of eric.mack
Sent: Wednesday, September 18, 2019 4:02 AM
To: SEBHC <se...@googlegroups.com>
Subject: Re: [sebhc] Re: Powering up H8 after over 30 years - Looking for advice on steps
MAKING PROGRESS!!Glenn, thank you for your kind help on the floppy issue.Tonight, Norberto sent me revised CPU and MEMORY diagnostics procedures that now work with my Z80 and 64K Ram (56K, Actually). Apparently the errors I had were due to the fact that the diagnostics in the manual assumed a 8080 CPU and 4 or 8K ram.Following Norberto's changes, CPU and Memory tests passed. So I know my machine works.Then, I saw your email and I followed your steps using on old 1.44mb 3.5” drive (no diskette) and I was able to get the drive to respond and spin up and seek using your boot sequence:0 [boot]3 [H37 device]0 [Port 170)1 [Unit 1]Of course, I have no bootable 3.5” diskettes.While waiting for Norberto to send me bootable 3.5” diskettes to test, I decided to go dig up my 5.25” floppy collection and some H8 era 5.25" drives.I found all my original source disks, and other than being subjected to 35 years of hot/cold cycles, they are in clean mint condition. I have all the stuff Heathkit sold, CPM and all the Microsoft languages and compilers. And, Wordstar! and DBASE 2 (I'm sure I have Supercalc too.). I also found boxes of never used 5.25" media, both hard and soft sector.I have no idea if any of these are readable, but physically, they are beautiful, having been sealed airtight for 35 years.I found some 5.25” DSDD diskettes that have “bootable CP/M” written on the label in handwriting that resembled a much younger me. 😊I played with a combination of drives and diskettes with no success. Two drives spun up one did nothing. A few gave boot error on the H8 (I have no terminal plugged in yet)Anyway, at least there is noise and a motor spins and no smoke.In your experience, have you found 40 year old 5” drives still work? Are there tricks to reconnecting – I seem to remember we needed terminators. It’s been so many years…In your experience have you found any of your orginal diskettes to be readable? I remember the doom and gloom discussions at HUG about how media was only going to last 7 years tops.So, that is where I am at, so far.
On Tuesday, September 17, 2019 at 1:52:41 PM UTC-7, Glenn wrote:
Eric: there are some subtleties associated with 3.5” drives. While you can get them to “look like” double-sided, double-density, 96TPI drives (~720K capacity) the cabling is slightly different than traditional 5.25” drives. I’m no expert but am being schooled by the experts on this list. I’ll send you some info off line…
- Glenn
From: se...@googlegroups.com <se...@googlegroups.com> On Behalf Of eric.mack
Sent: Tuesday, September 17, 2019 1:11 AM
To: SEBHC <se...@googlegroups.com>
Subject: Re: [sebhc] Re: Powering up H8 after over 30 years - Looking for advice on steps
Norby Wrote: "... It is easy to get a 3.5" floppy drive and boot HDOS or CP/M from it. Then later we can add booting from the H67 hard drive if needed."Can you direct me to some information about getting my H8 ready to boot CP/M from a 3.5" floppy drive? I would need to know how to interface and where to get the first bootable floppy? I can start that process if you can point me to information to study. (Or, if you do not want me to jump ahead, I'll wait and follow your lead.) Thanks.Eric
On Sunday, September 15, 2019 at 11:40:06 PM UTC-7, Norby wrote:
WOW! Great to see it working and you have 64KB of RAM. Please keep the H17 board out of the system for now. It is easy to get a 3.5" floppy drive and boot HDOS or CP/M from it. Then later we can add booting from the H67 hard drive if needed.Next steps will be to setup the Z80 switch settings to support your current hardware. Power down the H8 and check the dip switch on the Z80. See attached file.Switch:0 - off1 - on (H67 primary)2 - off3 - off4 - off (H67 primary boot)5 - off6 - off7 - offThen check the H37/H67 Ports:H37 = 170QH67 = 174QNext run the test routines from Heath. Link: http://sebhc.lesbird.com/documentation/hardware/H8/H8_As_Op_Sc.zipOpen the "OP+H8+595-2014-02..." file and test routines starts on page 4.:)Norberto
-------- Original Message --------
Subject: Re: [sebhc] Re: Powering up H8 after over 30 years - Looking
for advice on steps
-------- Original Message --------
Subject: [sebhc] Re: Powering up H8 after over 30 years - Looking for
advice on steps
From: "eric.mack" <Eric...@FasterAtWork.com>
Date: Sun, September 15, 2019 9:01 pm
To: SEBHC <se...@googlegroups.com>
OK, this evening I decided to unpack and inventory the H8 I built in my teens Brought back great memories.I could use some help getting this running. Here's a summary of the ev
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in...@esx.com
The reason some Heath diskettes were of a "high" quality, is we had a machine that would beat floppies until they failed. Some of the floppies lost enough oxide that the test tracks ended up clear, others just degraded to where they were not usable. Folks tracked how long various brands took before failure. I believe Warren also tested read/write in addition to head load/unload. The idea was to only sell the good diskettes, however, the company store somehow sold some of the "bad" diskettes too. Don't know how they did that--but they were cheap. The store manager mocked me when I insisted on buying the brand Warren had tested as best, and paid five to ten times as much for them over the cheap diskettes.
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Glenn Roberts
I’d be interested in your perspective on the head load solenoid in the original (Siemens) 100K drives. Back when I had a two-drive system I remember compiling or assembling programs always meant many minutes of solenoid “banging” off and on. I always wondered if that was really a good thing. I guess the goal was to minimize the head load time, on the assumption that whenever the head was loaded there was abrasion going on, but all the load/unload operations surely took their toll too? Was this a discussion or controversial topic? Later floppy drive designs seem to have done away with head loading so maybe this was just being overly cautious in the early days of the drives?
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Mark Garlanger
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eric.mack
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Kenneth L. Owen
Powered up, beep and the top and bottom two LEDs are on NOTHING on 7 Segment Displays
5 Power up and test power supply voltages, listen for pop and watch for magic smoke
6. If all is well, power off, connect PS to motherboard and repeat step #5
7. if all is well, power off and install CPU and Memory card and repeat step #5
How do those steps look?
Some questions
1. What are the minimum boards needed to test? Can I test with just CPU and Memory to get to the 377377? Do I need to add serial or any other boards to test?
2. Suppose it does power up, what to press on keypad to test very basic response?
3. If it does not power up, what are the most common thing that have shown up for people?
Thank you.
Eric
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eric.mack
Kenneth L. Owen
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eric.mack
<SPAN style='FONT-SIZE: 12pt; FONT-FAMILY: "Verdana",sans-serif; COLOR:
Norberto Collado
The fix on soldering pin 15 and 16 is for CP/M and after you boot from it. If it boots fine, no need to implemented it.
Can you try the following procedure on the H37 controller?
Link: http://sebhc.lesbird.com/documentation/hardware/H8/H8-37_Op_Sc.zip
Starting on page 15 of the WH-8-37-Op-… guide up to page 17.
The 1.44MB floppy drive is fine. Also check that the ribbon cable is fine, just in case.
Thanks,
Error! Filename not specified.
4. Next I guessed. :-). I looked at the labels and noted that the 0, 1,2 buttons looked boot related (and my vague memory).
I pressed 1 and the display said "Pri H17"
Error! Filename not specified.
I pressed CANCEL and then pressed 2 and the display said "sEC H37"
Error! Filename not specified.
I reset and pressed 0 and the display said "dEU" - No idea what that is.
Error! Filename not specified.
OK, so I assume those are all positive signs.I no longer have an H17 - must have sold it 25 years ago. I do have some drives from either H8 or H89. Some hard some soft sectors. I have some floppies from 35 years ago. No idea what might be readable after 35 years in a hot garage.
I have not connected H19 monitor or printer -- assuming those won't do anything until I can boot an OS.
What do you suggest I do next?
Thank you!
Eric
On Sunday, September 15, 2019 at 10:18:19 PM UTC-7, Norby wrote:
To power-up properly you will need to connect the Heath H37/H67 to the H8 backplane and connect the 16 pin ribbon cable back to the CPU as shown on your picture.
Pin 1 of the 5 pin connector is ground. Just solder it to the ground of the back of the front panel board. See attached picture.
Nice looking system.
Thanks,
Norberto
-------- Original Message --------
Subject: [sebhc] Re: Powering up H8 after over 30 years - Looking for
advice on steps
From: "eric.mack" <Eric...@FasterAtWork.com>
Date: Sun, September 15, 2019 9:01 pm
To: SEBHC <se...@googlegroups.com>
OK, this evening I decided to unpack and inventory the H8 I built in my teens Brought back great memories.
I could use some help getting this running. Here's a summary of the evening inspection.
H8 Chassis S/N 03815 – Assembled by a much younger me and used for 8-10 years without issue. In fact I launched a few businesses using this computer.
Error! Filename not specified.
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Norberto Collado
Ken,
This is a great document and thank you for putting this together.
Norberto
Error! Filename not specified.
4. Next I guessed. :-). I looked at the labels and noted that the 0, 1,2 buttons looked boot related (and my vague memory).
I pressed 1 and the display said "Pri H17"
Error! Filename not specified.
I pressed CANCEL and then pressed 2 and the display said "sEC H37"
Error! Filename not specified.
I reset and pressed 0 and the display said "dEU" - No idea what that is.
Error! Filename not specified.
OK, so I assume those are all positive signs.I no longer have an H17 - must have sold it 25 years ago. I do have some drives from either H8 or H89. Some hard some soft sectors. I have some floppies from 35 years ago. No idea what might be readable after 35 years in a hot garage.
I have not connected H19 monitor or printer -- assuming those won't do anything until I can boot an OS.
What do you suggest I do next?
Thank you!
Eric
On Sunday, September 15, 2019 at 10:18:19 PM UTC-7, Norby wrote:
To power-up properly you will need to connect the Heath H37/H67 to the H8 backplane and connect the 16 pin ribbon cable back to the CPU as shown on your picture.
Pin 1 of the 5 pin connector is ground. Just solder it to the ground of the back of the front panel board. See attached picture.
Nice looking system.
Thanks,
Norberto
-------- Original Message --------
Subject: [sebhc] Re: Powering up H8 after over 30 years - Looking for
advice on steps
From: "eric.mack" <Eric...@FasterAtWork.com>
Date: Sun, September 15, 2019 9:01 pm
To: SEBHC <se...@googlegroups.com>
OK, this evening I decided to unpack and inventory the H8 I built in my teens Brought back great memories.
I could use some help getting this running. Here's a summary of the evening inspection.
H8 Chassis S/N 03815 – Assembled by a much younger me and used for 8-10 years without issue. In fact I launched a few businesses using this computer.
Error! Filename not specified.
To view this discussion on the web visit https://groups.google.com/d/msgid/sebhc/7008FD98399541108CDD343A372E6331%40KenPSPC.
Norberto Collado
I forgot! One common problem with the H37/H67 are the regulators 3-pin power connector. Make sure that they are making good contact on both regulators after all these years.
Norberto
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Glenn Roberts
Also worth checking the jumpers (pictorial 8, p. 19). Physically inspect board of course, check that the potting is undisturbed on the adjustment potentiometers in the upper left of the board
The “straight through” ribbon should work with a single 3.5” drive but as others have said it will be unit 1 (for unit 0 you need a twist in the cable or an older drive with selectable jumpers, e.g. Epson SMD-300)
If it were me I wouldn’t hesitate to hook up one of the5.25” 360K drives and use the soft-sectored H37 test diskette (which you previously indicated you have) to at least see if that boots up. I believe those test disks boot right into the test program?? Or if you have any older soft sectored 5.25” disks that you think are bootable…
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