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ridata
November 21st, 2017, 05:52 AM
I will try to explain as best as i can.

-I was able to buy an IBM PS/2 Model30 8530 8086cpu very cheap.
-The 8086 works, boots, hard drive sometimes has to retry to read some files, BUT I get DOS shell, i can use DOS.
-The 8086 has an ALPS 720k floppy drive. DOES NOT WORK. when i insert a 720formatted floppy it spins, tries to read and gives an error about the media or something like that or track 0, canīt remember the specific error.
-If i insert other floppy discs and i try to format, it gives the same error.
-All floppy discs have the hole covered with tape and were checked on another pc and formated as 720k
-I have ordered an XTIDE online, because the hard drive will die sooner or later.
-Im scared that the battery will drain, big yellow battery on the riser card, but if i take it out and replace it, i will need to use the 8086 IBM sistem diagnostics floppy disc else it will never boot again.
-I have checked the floppy disc, and i see one 1uf 50v capacitor leaking on its bottom part.


My thoughts:
1) I donīt give a damn about the floppy drive, the only problem i have with a non working floppy is the case where the battery drains and i cannot boot the IBM floppy setup disc, and the machine wonīt boot ever again.

2) Even if i have an XTIDE, i would be able to use the PC forever with other IDE hard drives, as long as the battery does not drain. If it drains im ****ed.


Need to ask for advice on:

1) What are my choices with this pc?
2) Can i solder on the back of the riser card 2 cables and connect a second battery at the same time? (to prevent the system asking for diagnostic/setup floppy disc in the future since i have a broken floppy drive)
3) I saw someone fixed a drive replacing capacitors, but it was another model a matsushita or mitsumi drive, Mine is an Alps 720k drive DFL413C04A
4) Can i connect a generic floppy drive into this machine? has that ever worked? I noticed the motherboard has a 40 pin connector. And i think that PIN 1-36 is the same as on a generic floppy drive and the rest (pins 37 to 40) provide power to the drive.
Maybe i can forget about power mods and just use a second power supply to provide floppy connector power, and use a 40 pin ide cable and connect it to the generic floppy drive.



https://s2.postimg.org/l771sy561/flopp.jpg

Kazblox
November 21st, 2017, 06:59 AM
The pinout of the drive here is a standard edgecard interface with extra power. If you're cheap and lazy, you can just hook up part of that female edge connector cable to a regular floppy drive with an edge connector adapter, and then solder on some wires from existing solder joints that provide 5V and 12V on the motherboard. Thankfully, this is much easier to do than with a 1.44M drive on a later PS/2; you need to hook up a resistor attached to 5V to several pins in order to get 1.44M support.


...or you can just buy a drive from here instead; https://www.ebay.com/itm/Vintage-IBM-Type-8525-PS-2-Floppy-Drive-untested/401442422693?hash=item5d77d53fa5:g:8c4AAOSwPzhaDBN U

chulofiasco
November 21st, 2017, 08:35 AM
I'd pass on that listing.. I've tested a boatload of these, and half of them fail.

Get at me if you need a replacement. I can get one tested.

Also, there should be a cable available with pins instead of card edge... you're not stuck with a card-edge floppy.

ridata
November 21st, 2017, 08:58 AM
The pinout of the drive here is a standard edgecard interface with extra power. If you're cheap and lazy, you can just hook up part of that female edge connector cable to a regular floppy drive with an edge connector adapter, and then solder on some wires from existing solder joints that provide 5V and 12V on the motherboard. Thankfully, this is much easier to do than with a 1.44M drive on a later PS/2; you need to hook up a resistor attached to 5V to several pins in order to get 1.44M support.


...or you can just buy a drive from here instead; https://www.ebay.com/itm/Vintage-IBM-Type-8525-PS-2-Floppy-Drive-untested/401442422693?hash=item5d77d53fa5:g:8c4AAOSwPzhaDBN U

I think that your explanation was something found on another post, that first i did not understand at all because the images of photobucket got removed, but im kind of understanding now because i found the image in low quality in google search.

https://s2.postimg.org/p3y5tv4i1/resistor.jpg


explained here: http://www.vcfed.org/forum/showthread.php?50816-Again-a-faulty-PS-2-floppy-drive
and here: http://webpages.charter.net/zip4dos/PS2/

So those resistors (between 1k~10k) go connected to those pins, i wonder where did he took the 5volt end since i dont see anything soldered to 5volt on that picture for the other end of the resistors.

then i can just take a 40pin IDE cable, connect it to the motherboard, and on the other end of the ide cable i can cut it so i have 36pin only, and then i can just use another power supply to provide power to the floppy drive.

that would be the most cheap, and without the hassle of buying extra parts, just an ide cable and resistors, nothing else, to actually test that the floppy works and reads correctly.

Im I correct? or i missed things?

g4ugm
November 21st, 2017, 09:05 AM
All the above is good advice, but can I add a couple more points....

These drives suffer because the air flows in through the drive slot. There is no flap so the heads get dirty. Try a cleaning floppy first.

e.g.

https://www.ebay.com/itm/3-5-Drive-CD-Drive-cleaning-Kit-R4/192349661831

the caps do fail so its worth trying a replacement. I have recovered drives like that..

PeterNC
November 21st, 2017, 09:21 AM
Install a HDD (SCSI, RLL, MFM, XT-IDE, IBM FRU) and use INTERSVR / INTERLNK in case you need a to access a much larger HDD on another system. I have owned a couple of 8530s and eventually got tired of them as most games are very slow on a 8086 (or V30).

Kazblox
November 21st, 2017, 10:27 AM
Woops! I didn't realize that earlier PS/2 drives used a more traditional cable setup instead of having just a female card edge socket on Models 80 and up.

FYI, the standard floppy drive pin count for AT clone drives are 34 pins, not 36. If you plan to cut up an IDE cable, the pins you should cut off on the other end are pins 35 to 40. Pin 38 of the IDE cable should go to 12V and pin 40 of the same cable should go to 5V. Also, I hinted that YOU DO NOT HAVE TO ATTACH RESISTORS if you want to use only 720k. No idea if all 8530 models support 1.44M, anyways.

Stone
November 21st, 2017, 10:48 AM
All the above is good advice, but can I add a couple more points....

Try a cleaning floppy first.That is the best first step to take before doing anything else to try and get a malfunctioning drive working.

It's quite conceivable that dirty heads account for more floppy failures than all the other possibilities combined.

ridata
November 21st, 2017, 11:29 AM
Gotcha, i got Q-tips Cotton Swabs, i got isoprophil alcohol, i will try gently cleaning inside.

but see it sounded strange for me that for this mod, you will be sending 5volts into pins pins 8, 26,28,30 and 4 on the floppy pcb, and those pins are also connected on the IDE cable sending voltage also to the motherboard so, i thought it was risky maybe you can break something on the motherboard

it will be safe?

ridata
November 21st, 2017, 11:52 AM
this is the cheap ass mod i will use

(Black) goes to motherboard
(Blue) goes to floppy drive
+
resistors on some of the pins of the floppy drive clone
+
5 volts feeding the other end of those resistors
+
external power supply to feed the clone floppy drive.


https://s2.postimg.org/4qkt3ywyx/Sin_t_tulo.jpg

ridata
November 22nd, 2017, 03:55 AM
i did the mod tonight without the resistors

-In the first picture i just took the original ide cable out of the motherboard.
-On the second picture you can see my modded IDE cable, which has 6 cables on the left side that werre removed (bottom left side) and plastic cut.
-On the third picture you see how i connected the cable to my clone floppy drive.

I used another power supply to connect the floppy, turned on the power supply, the floppy drive always has green light and motor is always spinning.
I turn on the 8086 and i get an error 63 or 61 i cant remember the number, and the drive does not work at all

im wondering what im doing wrong, pins 1 to 24 were supposed to be the same as 34pin IDE.


https://s17.postimg.org/bd8c4vl2n/number1.jpg
https://s17.postimg.org/5can7u8r3/number2.jpg
https://s17.postimg.org/m025ae8of/number3.jpg

pcdata76
November 24th, 2017, 12:28 PM
I've reuploaded the lost images again and replied to the relevant topic. One ends of the pull-up resistors are soldered to the junction of the ferrite bead (5V). I've encircled with blue.

https://i.imgur.com/8DQlRpx.png



I think that your explanation was something found on another post, that first i did not understand at all because the images of photobucket got removed, but im kind of understanding now because i found the image in low quality in google search.

https://s2.postimg.org/p3y5tv4i1/resistor.jpg


explained here: http://www.vcfed.org/forum/showthread.php?50816-Again-a-faulty-PS-2-floppy-drive
and here: http://webpages.charter.net/zip4dos/PS2/

So those resistors (between 1k~10k) go connected to those pins, i wonder where did he took the 5volt end since i dont see anything soldered to 5volt on that picture for the other end of the resistors.

then i can just take a 40pin IDE cable, connect it to the motherboard, and on the other end of the ide cable i can cut it so i have 36pin only, and then i can just use another power supply to provide power to the floppy drive.

that would be the most cheap, and without the hassle of buying extra parts, just an ide cable and resistors, nothing else, to actually test that the floppy works and reads correctly.

Im I correct? or i missed things?

ridata
January 13th, 2018, 08:59 PM
I am so stupid

so blind, i was doing your mod but i never understood why it did not work.

i think it is because i bought a box full of old ide cables, and used a 40 pin cable that DID NOT HAVE THE TWIST between 10 to 16.
Mine were straight, no twist as shown here


https://s17.postimg.org/m025ae8of/number3.jpg



I Will try to finish it tomorrow:

https://s9.postimg.org/d1mcqhv67/flop.jpg


so the resistors on the bottom of the drive are also needed then?