Here's a high-res picture of the component side. Solder side follows.
http://abload.de/img/p7150865mzoyn.jpg
http://abload.de/img/p7150865mzoyn.jpg
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Zenith Supersport 8088 (again) - "fake hdd" terminal on hdd connector
- Thread starter giobbi
- Start date
giobbi
Veteran Member
Thank you Timo. Excellent picture, very useful. Well, I can see no differences between the two boards (except for the missing eprom). They are the same PCB revision too.
Now take a look at this picture:
It's a screenshot from a youtube clip I previously mentioned about an HDD model. It has the 10D eprom you have, and the 11D eprom I have. It could probably mean the 11D eprom is the HDD bios, but it must to be enable by some undocumented jumper. I can't imagine another explanation. Since I didn't find any difference on the component side, the difference (if any) could be on the solder side.... or, frankly, I can't imagine what it could be else. Well, I will wait for your next pic, solder side...
Attachments
Here's the picture of the solder side:
http://abload.de/img/p7160867d3qf5.jpg
Ignore the dust - had no time to clean the board yet.
http://abload.de/img/p7160867d3qf5.jpg
Ignore the dust - had no time to clean the board yet.
giobbi
Veteran Member
Here's the picture of the solder side:
http://abload.de/img/p7160867d3qf5.jpg
Ignore the dust - had no time to clean the board yet.
...not so dirty
Thank you for the pic. Surprisingly, there isn't any difference on the solder side (at least I didn't notice anything different). However, I noticed the 2nd FDD connector was probably added by somebody, since it's not a standard FDD connector. It would probably mean your board was modified by somebody when the HDD died.
Maybe your bios revision allows to boot without the 2nd eprom (11D).
Did you ever seen this computer working? If yes, do you remember if there was a message, like "+++ drive not ready +++" or "+++ drive not present +++" or something else, during the boot, that forced you to press ESC to continue?
It was gifted to me and never worked since it's in my possession. However, the "Drive not ready" message among other disk-related error messages are indeed in the 11D ROM dump that you uploaded earlier. The ROMs look independent, so there must be a way to boot the machine with 11D removed.
Can you upload pictures of your board as well? Maybe I can spot some difference.
Can you upload pictures of your board as well? Maybe I can spot some difference.
giobbi
Veteran Member
I tried to do that, it didn't boot; simply it lights on the backlight, nothing more.
Of course! I had to take them under the sun to get a better resolution. I hope shadows won't annoying; I put a couple of them per side.
www.verrua.org/zenith_supersport/mb1.jpg
www.verrua.org/zenith_supersport/mb2.jpg
www.verrua.org/zenith_supersport/mb3.jpg
www.verrua.org/zenith_supersport/mb4.jpg
maybe you'll have more luck chasing differences ^_^
I'll give fixing my Supersport a try this weekend.
Thanks for your pictures. Did the notice the different settings of the dip switches? Haven't validated if they are actually set correctly on my mainboard, but maybe you should try with the same settings as on mine and with 11D removed?
Thanks for your pictures. Did the notice the different settings of the dip switches? Haven't validated if they are actually set correctly on my mainboard, but maybe you should try with the same settings as on mine and with 11D removed?
giobbi
Veteran Member
Ok, the funny part: I removed the eprom and now it works fine with my switches configuration. I don't know what happened and/or where I went wrong in my previous test, when it hung during the boot without the 11D eprom. boooohhhh????
However you should opt for my switches configuration; yours is a wrong set in a 2 FDD machine.
Putting #1 swt = OFF, you activate the LED for the left floppy.
Putting #7 swt = OFF, you will activate a 2 FDD configuration. If you leave 7 and 8 = ON, A: and B: units will refer to the right drive. So if you type:
A:\> b: [return]
you will get the message "put a disk into B: drive and press a key when ready" (more or less). And when you press a key, the right drive will become the B: drive, LOL, it's an old behavior from the DOS era I almost forgot.
Well, it seems we solved! Thank you for your help, Timo, it was very useful!!! Now let me know how it's doing your fix (you would use this same thread or open a new one, your choice).
I will open a new thread explaining what I did and how to convert a Zenith Supersport 1 HDD, 1 FDD into a 2 FDD one.
--Giovi
giobbi
Veteran Member
Glad to hear that you got it working.
I'm currently re-assembling my Supersport after having finished cleaning all parts. I'll correct the dip switch settings and then give it a try to see if it does more than before.
In case of troubles, I believe the best thing you can do is to not connect the FDDs and the keyboard and try to fire it up. I've seen if something wrong is plugged, it doesn't go on (dead computer).
giobbi
Veteran Member
I didn't look too much at power board, but I believe it's quite simple, should be easy to fix it... however it has the monitor connector embedded, so I don't know if the two model can be replaced.... well, maybe. I've never seen the 286 model, so I don't know the differences.
ropersonline
Experienced Member
- Joined
- Jun 17, 2011
- Messages
- 153
this is the connector for the HDD controller. There's something plugged in it...
To me, it looks like there might simply be two jumpers in there. Maybe. By carefully perspective-distorting this image and overlaying it with the hi-rez pic of the board elsewhere ITT, and by then increasing and reducing opacity, I think I've tentatively worked out that the jumpers (if that's what's really there; if it's not just dirt or compression artefacts) might be sitting next to the 1 and 5 in CN15: The pin pair closest to the 1, and the other one below that. Well, maybe. If I'm all wrong, and you release the blue magic smoke from your board based on this hypothesis, don't blame me. I'm pretty much mostly guessing. You can download the GIMP file I did this with and see for yourself whether this makes any sense.
giobbi
Veteran Member
LOL, no magic smoke this time
I already tried to play with the picture, with no luck. Then Timo W. told me his machine has no jumpers there. So we did some comparisons and we found out you can simply remove the 11D eprom and the laptop will work as 2 the FDD model. So easy! You can read about what we discovered in this same thread.
I've left some instructions for future reference here:
http://www.vintage-computer.com/vcf...persport-with-broken-HDD-into-a-2-FDD-machine
However, thank you for your effort.
Yes, it's simple to fix, but I have to get replacement caps first. Using the power board from the 286 model would be a quick(er) solution to get it running. Have to give it a try later this week.
ropersonline
Experienced Member
- Joined
- Jun 17, 2011
- Messages
- 153
LOL, no magic smoke this time
I already tried to play with the picture, with no luck. Then Timo W. told me his machine has no jumpers there. So we did some comparisons and we found out you can simply remove the 11D eprom and the laptop will work as 2 the FDD model. So easy! You can read about what we discovered in this same thread.
I've left some instructions for future reference here:
http://www.vintage-computer.com/vcf...persport-with-broken-HDD-into-a-2-FDD-machine
However, thank you for your effort.
Thanks giobbi. All the best.