A couple of retros I'm working on.

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Re: A couple of retros I'm working on.

Postby jaZz_KCS » 2018-1-16 @ 20:40

@ Formulator

The problem isn't the conversion from 34-pin to 26-pin, but rather the proprietary pin-out.
The original proprietary floppy drive's pin-out, although having a 26-pin connector (at least on the planar side) was completely different. The connector on the floppy side, was completely proprietary, at least I havn't seen one of those being used on full height drives. Also we cannot use a generic adapter as we therefore have the power somewhere amongst those pins as well (!) simply translating from 34-pin to 26-pin would result in the drive getting power through pins it is not supposed to and it will likely take damage.
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-16 @ 20:44

Not sure what I have here ..
but I ignored the device ID check the programmer software moaned....and performed a read with TL866 ..
what I got is in the attached zip ..
But did I read the correct chip even ?
Ian ..over to you buddy ..
saved as a bin file not hex
VS
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T5200 bios.zip
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Re: A couple of retros I'm working on.

Postby Formulator » 2018-1-16 @ 21:04

jaZz_KCS wrote:The problem isn't the conversion from 34-pin to 26-pin, but rather the proprietary pin-out.


With the exception of the two pins tied to ground, this adapter satisfies the correct pinout. Check the maintenance manual if there is any question.

Also we cannot use a generic adapter as we therefore have the power somewhere amongst those pins as well (!)


Yes we can in this case, as the power inputs are tied to the correct pins on the adapter.

The purpose of this post is not to confirm whether this method works or not, it does indeed work, and multiple users have employed it successfully.
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-16 @ 21:40

So ..looks sort of right ...
looked through the retrieved code and although it isn't immediately legible ..some ascII in the wrong order ..
One can clearly make out words Phoenix and copyright ..
err ..sort of ..
lol
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bios image..jpg
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Re: A couple of retros I'm working on.

Postby jaZz_KCS » 2018-1-16 @ 21:41

Formulator wrote:
jaZz_KCS wrote:The problem isn't the conversion from 34-pin to 26-pin, but rather the proprietary pin-out.


With the exception of the two pins tied to ground, this adapter satisfies the correct pinout. Check the maintenance manual if there is any question.

Also we cannot use a generic adapter as we therefore have the power somewhere amongst those pins as well (!)


Yes we can in this case, as the power inputs are tied to the correct pins on the adapter.

The purpose of this post is not to confirm whether this method works or not, it does indeed work, and multiple users have employed it successfully.



So the two patchwires modification is needed for the 5200 specifically in this case? Sorry I misunderstood, I thought the T3200SX would have a different pinout but apparently it has the standard 26-pin layout.
Would the modification you mentioned also work for me on the T3200SX? I think in regards to the adapter you mentioned space could be a concern.

TABLE B-9 FDD Connector Pin Assignment (T3200SX)

ÚÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÂÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÂÄÄÄÄÄ¿
³ Pin ³ Signal ³ I/O ³ Pin ³ Signal ³ I/O ³
ÃÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÅÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÅÄÄÄÄÄ´
³ 1 ³ VCC ³ O ³ 2 ³ INDEX;000 ³ I ³
³ 3 ³ VCC ³ O ³ 4 ³ FDSELA;000 ³ O ³
³ 5 ³ VCC ³ O ³ 6 ³ DSKCHG;000 ³ I ³
³ 7 ³ VCC ³ O ³ 8 ³ READY;000 ³ I ³
³ 9 ³ NOTCH0;000 ³ I ³ 10 ³ MONA;000 ³ O ³
³ 11 ³ LOWDNS;000 ³ O ³ 12 ³ FDCDCR;000 ³ O ³
³ 13 ³ GND ³ ³ 14 ³ STEP;000 ³ O ³
³ 15 ³ GND ³ ³ 16 ³ WDATA;000 ³ O ³
³ 17 ³ GND ³ ³ 18 ³ WGATE;000 ³ O ³
³ 19 ³ GND ³ ³ 20 ³ TRACKO;000 ³ I ³
³ 21 ³ GND ³ ³ 22 ³ WPROTC;000 ³ I ³
³ 23 ³ GND ³ ³ 24 ³ RDDA;000 ³ I ³
³ 25 ³ GND ³ ³ 26 ³ SIDE;000 ³ O ³
ÀÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÁÄÄÄÄÄÄÄÄÄÄÄÄÄÄÄÁÄÄÄÄÄÙ
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Re: A couple of retros I'm working on.

Postby IanB » 2018-1-16 @ 22:04

Vipersan wrote:Well Ian ..
already started when I read your post ..
so please take a look at the floppy drive end of my lead ?
does it look right ?
if not I'll start again ..

It looks right but it's difficult to be certain without seeing a closeup of the IDC with the top removed. However when drawing up a list of pin numbers I noticed a possible mistake on the original wiring:
There are two density pins on the 26 way, an input which makes the drive change density and an output which shows the detected density from the extra hole in high density floppies. There is only one density pin on the 34 way and I think I connected it to the wrong one on the 26 way.
It doesn't actually seem to matter as the drive seems to ignore that pin and use the extra hole to switch density anyway but I would like it to be correct.
I've removed my floppy photos for now until I can confirm which is right but don't cut off the unused wires in your cable as one will probably be required.
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Re: A couple of retros I'm working on.

Postby Formulator » 2018-1-16 @ 22:12

So the two patchwires modification is needed for the 5200 specifically in this case? Sorry I misunderstood, I thought the T3200SX would have a different pinout but apparently it has the standard 26-pin layout.
Would the modification you mentioned also work for me on the T3200SX?


Yes, I double-checked and the FDD pinout from the motherboard on the T3200SX and the T5200 are identical, so this modification would work. In fact, I believe the user on VCF tried it on a T3200SX and got it to work so I tried it on my T5200.

The reason I went this direction was to see if there was a solution that did not require creating a custom cable, which of course works just as well.

I also forgot to mention that I removed the molex connector from the adapter and soldered the wires in directly.
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Re: A couple of retros I'm working on.

Postby IanB » 2018-1-16 @ 22:33

Vipersan wrote:what I got is in the attached zip ..
But did I read the correct chip even ?
Ian ..over to you buddy ..
saved as a bin file not hex

Didn't realise you had an EPROM programmer, that's useful.
It's the right chip and it's a Phoenix BIOS, the one I have is an Award BIOS. I've programmed a 27C1024 with yours and it will let me boot off the CF card using my modified XTIDE although it hangs for a few seconds on a warm restart.
I'll have to dismantle the machine to remove the XTIDE EPROM from the network card to try it standalone.
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-16 @ 22:41

IanB wrote:
Vipersan wrote:what I got is in the attached zip ..
But did I read the correct chip even ?
Ian ..over to you buddy ..
saved as a bin file not hex

Didn't realise you had an EPROM programmer, that's useful.
It's the right chip and it's a Phoenix BIOS, the one I have is an Award BIOS. I've programmed a 27C1024 with yours and it will let me boot off the CF card using my modified XTIDE although it hangs for a few seconds on a warm restart.
I'll have to dismantle the machine to remove the XTIDE EPROM from the network card to try it standalone.


Thanks Ian ..
My main worry is having the right settings to actually flash a device ..
I dont know if the TL866 will play nice with older chips ..
perhaps it would be better to try and order a couple of eproms to blank and experiment with ..
but ..all that said ..I may well looking at a bios upgrade afterall ..
:D
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-16 @ 22:48

I have found a listing for 2 chips ..type
D27C1024D-15 64Kx16 64X16 EPROM CERAMIC DIL 27C1024 150NS 1MBIT
will these be suitable Ian..???
rgds
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Re: A couple of retros I'm working on.

Postby IanB » 2018-1-16 @ 23:54

Vipersan wrote:D27C1024D-15 64Kx16 64X16 EPROM CERAMIC DIL 27C1024 150NS 1MBIT
will these be suitable Ian..???

I have a few of that exact part number and have been using them when testing BIOS patches so I would say definitely OK as long as your programmer can program them.
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Re: A couple of retros I'm working on.

Postby IanB » 2018-1-16 @ 23:59

Here are the patched and unpatched versions of the Award BIOS I posted to the other forum (only 528MB change in the patched version)
Don't forget that the IDE cable likely has one connector fitted backwards so you can't use the standard cable to plug into another IDE drive without checking that and if necessary removing the keyway bump.
If in doubt, use a standard IDE cable for testing.
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Re: A couple of retros I'm working on.

Postby jaZz_KCS » 2018-1-17 @ 01:47

IanB wrote:
Vipersan wrote:what I got is in the attached zip ..
But did I read the correct chip even ?
Ian ..over to you buddy ..
saved as a bin file not hex

Didn't realise you had an EPROM programmer, that's useful.
It's the right chip and it's a Phoenix BIOS, the one I have is an Award BIOS. I've programmed a 27C1024 with yours and it will let me boot off the CF card using my modified XTIDE although it hangs for a few seconds on a warm restart.
I'll have to dismantle the machine to remove the XTIDE EPROM from the network card to try it standalone.


The XTIDE is probably overriding it. I wouldn't be surprised if without it the BIOS would automatically fallback to "no drive" if it doesn't detect a Connor on it's own IDE connector, but maybe his BIOS is old enough, as I think only the later revisions have this limitation. Can you try using his BIOS and attaching the CF adapter to the Toshiba's IDE? If it doesn't work, it would definitely be quicker and cheaper for Vipersan to flash a new BIOS than to opt for an XTIDE custom network card.

Formulator wrote:
So the two patchwires modification is needed for the 5200 specifically in this case? Sorry I misunderstood, I thought the T3200SX would have a different pinout but apparently it has the standard 26-pin layout.
Would the modification you mentioned also work for me on the T3200SX?


Yes, I double-checked and the FDD pinout from the motherboard on the T3200SX and the T5200 are identical, so this modification would work. In fact, I believe the user on VCF tried it on a T3200SX and got it to work so I tried it on my T5200.

The reason I went this direction was to see if there was a solution that did not require creating a custom cable, which of course works just as well.

I also forgot to mention that I removed the molex connector from the adapter and soldered the wires in directly.

Thank you very much for the info. I will probably opt for an adapter in this case, I just have to find out whether there is enough space behind the FDD, as in the T3200SX the cable is very short due to the connector being quite close to the drive itself. But if you say that a fellow on VCF used it successfully in a T3200SX, then I have good hopes.

IanB wrote:Here are the patched and unpatched versions of the Award BIOS I posted to the other forum (only 528MB change in the patched version)
Don't forget that the IDE cable likely has one connector fitted backwards so you can't use the standard cable to plug into another IDE drive without checking that and if necessary removing the keyway bump.
If in doubt, use a standard IDE cable for testing.


Aye, if in doubt, check the original cable from the old Conner drive, IF you still have it. In my case (T3200SX) the cable had the connector's the correct way around. (@Vipersan)
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-17 @ 10:33

Chips on order should be here quickly as they are only travelling about 70 miles by post..
2x chips @ £5 inc
I'll take the delay time to clean the keyboard ..
Some keys are dead-ish and unresponsive ..
Recommendations for this appreciated..
Is it safe to use servisol contact cleaner spray here ??
rgds
VS
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-17 @ 11:57

Bit of a longshot ..but maybe it might be a way forward for the Toshiba T4900CT laptop ...as it does have an LPT port ??
I just bought one of these ..
https://www.ebay.co.uk/sch/i.html?_from ... 1&_sacat=0
No idea if it will work ..but a suitable ultra slim floppy for this is rare it seems.
Comments welcomed..
rgds
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Re: A couple of retros I'm working on.

Postby jaZz_KCS » 2018-1-17 @ 16:43

I think the external Compaq floppy drives over LPT were only compatible with the Compaq Laptops / DockingStations they came with.

Have you opened the T4900CT yet? I would be interested to see if the cable on the floppy-side is indeed soldered on. Even if so, if the ribbon cable has a normal super slim-drive pinout, you would still be able to substitute the drive with any standard slim-drive you can get your hands on.
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-17 @ 16:47

jaZz_KCS wrote:I think the external Compaq floppy drives over LPT were only compatible with the Compaq Laptops / DockingStations they came with.

Have you opened the T4900CT yet? I would be interested to see if the cable on the floppy-side is indeed soldered on. Even if so, if the ribbon cable has a normal super slim-drive pinout, you would still be able to substitute the drive with any standard slim-drive you can get your hands on.

Dont know if you can tell from the picture I posted previously ...
but it is a flexible brown ribbon ..and anchored at the drive end so not removeable ..
rgds
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-17 @ 17:29

this is it I believe ..
https://www.impactcomputers.com/p000197860.html
same Image I posted earlier ..
Still available from this link ..but at silly money ..and add import duties and postage ..
well ..lets just say ..
I can't justify it.
rgds
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Re: A couple of retros I'm working on.

Postby IanB » 2018-1-17 @ 19:57

Vipersan wrote:Not sure what I have here ..
but I ignored the device ID check the programmer software moaned....and performed a read with TL866 ..
what I got is in the attached zip ..
But did I read the correct chip even ?
Ian ..over to you buddy ..
saved as a bin file not hex
VS

I've now had a chance to test this Phoenix BIOS on its own and it won't boot with other drives as you discovered. I'm not sure if this is specific protection or just a sanity check, e.g. it might be checking that the geomentry of the drive exactly matches the geometry set in the CMOS/BIOS before booting so fitting anything else will cause it to fail. It will boot with my modifed XTIDE ROM but that may not be fully compatible as it uses some unused BIOS workspace in the Award BIOS which might be used in the Phoenix BIOS.
You best option is to install the 528MB Award BIOS for now and fit a drive greater than or equal to 528MB. If you want a bigger drive you will have to use the XTIDE BIOS in a network card. (The standard version will work but my modified one has greater OS compatibility)

I finalised the floppy cable and ended up making two changes:
The first change fixed an error so you need to remove wire 9 from pin 2 and connect wire 11 to pin 2 instead.
The second change was to increase compatibility with some floppies and involved removing wire 8 from pin 15 and connecting to pin 5 instead. (You don't need to make this change unless you have one of the problem drives)

I posted full instructions in my thread here which might make it easier for others in the future to find it:
viewtopic.php?f=46&t=57998#p642629
Last edited by IanB on 2018-1-18 @ 00:00, edited 1 time in total.
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Re: A couple of retros I'm working on.

Postby Vipersan » 2018-1-17 @ 20:08

Thanks Ian ..
I have printed off the pin connections you posted in the other thread.
cheers
VS
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