IDE Interface Fried?

[MoonDragn]

I brought a new 2 device ide ribbon and was testing out the cable and it must have been wired wrong because I started smelling a burning smell from the IDE compact flash adapter.

I went back to my original ribbon and it can no longer find the scsi devices using hdtoolbox.

I tried plugging in my 2.5" ide hd and that is not picking up either.

So the question is, what got fried? The computer still boots up fine with a floppy workbench and it still picks up the PCMCIA card just fine, just not the SCSI so I know I didn't fry the gayle chip (well not 100% sure since the ide controller is on diff pinouts). Is there a fuse in the path somewhere on this ide interface to the chip?

Somebody HELP please

[jlin_au]

Which amiga model are you talking about and which board revision for that model? That will at least point us to the correct schematics and PCB layouts for your system.

The amiga 1200 and 600 are the only models with both a built in PCMCIA and a built in IDE interface but neither model has a Gary chip installed.

Both models instead have a Gayle chip that is used to access their built in PCMCIA interface and built in unbuffered IDE interface. A version of the Gayle chip is also present in the Amiga 4000 for use with its IDE interface. An Amiga 4000 lacks a PCMCIA interface.

If you're lucky the faulty IDE cable only burnt out your IDE compact flash adapter and your compact flash card due to the 5V power and 0V on the 44pin IDE cable being applied to the wrong connections on these devices.

Confirm that you have your original IDE cable plugged in the correct way round into your motherboard; the pin with the downward pointing arrow near the red wire should be near the pin 1 of the IDE header on the motherboard.

Unfortunately the IDE header on most Amiga 600 and 1200 machines are unpolarized so the 44 pin IDE cable can be plugged in the wrong way round. Most 2.5" IDE harddrives have a polarized IDE connector that forces you to insert that end of the cable into the drive in the correct orientation.

[MoonDragn]

Yes, this is for the Amiga 1200. I am not sure which revision I have. It is the Gayle chip not the Gary chip.

The IDE interface is not picking up any IDE drives real HDs or compact flash. The compact flash still works on a PC so that is ok but I think the diodes on the adapter are fried.

I knew about the polarization and I made sure the red pin indicating pin 1 was plugged into pin 1 of the motherboard and I was sure I plugged the adapter in the right way too. I'm not exactly sure what happened.

I hate to have to get a new Gayle and solder it, even though I do have a hot air gun, SMDs are annoying.

Any idea if this thing replaces the Gayle's IDE I/O?

http://amigakit.amiga.store/product_...ducts_id=12692

from the way it looks in the picture, it looks like it bypasses the IDE controller on the Gayle and reroutes the IDE to the chip on the back of the socket board.

May be a good work around if the Gayle IDE lines are fried.

Other option is the wait for my Vampire V1200 V2 to be available... That thing has a fast IDE port on it... But long waiting list...

[jlin_au]

I'm assuming that by hdtoolbox you have tried booting the 1200 with AmigaOS 3.0 or 3.1 Hard drive install disk to see if it can see your 2.5" HDD or your CF card on your CF to IDE adapter.

Make sure that your CF adapter and HDD are set to be IDE "master" drives when you test each separately. The default AmigaOS 3.0/3.1 scsi.device driver only looks for the IDE master on the 1200's IDE interface.

Does the HDD LED indicator next to the keyboard blink when your boot your 1200? If it does then your 1200's IDE port and the Gayle chip may still be ok.

The amigakit adapter clips on top of the Gayle chip and must be used with Amigakit's A1200/A600 4XIDE BUFFERED IDE INTERFACE (https://amigakit.amiga.store/product...roducts_id=465) that must be plugged into the Amiga 1200's native IDE port as well. If your Gayle is damaged then using the amigakit FASTIDE A1200 ADAPTER FOR 4XIDE INTERFACE with the required A1200/A600 4XIDE BUFFERED IDE INTERFACE will probably fail as a solution.

The Elbox FASTATA 1200 MK-V IDE CF/SATA (also from Amigakit: http://amigakit.amiga.store/product_...oducts_id=1052) might be a better solution. It's one of the original Fast IDE interfaces for the Amiga 1200 that plugs into the two rom sockets (roms moved on top) with a supplied 2nd adapter over the Gayle chip with the only connection to the 1200's IDE connector being on pin 39(?) so it can drive the 1200's HDD activity indicator.

The FastATA may work with a faulty 1200 Gayle chip as it seems to use the 1200's full 32 bit data bus directly via the 1200's ROM socket data lines instead of via the Gayle chip IDE port lines ( see http://www.elbox.com/products/fast_ata_1200.html ).

[MoonDragn]

Cool Thanks. I will look into that.

For the HDD, the H. Disk light comes up for a second when I first turn on the computer, but it stays off no matter what happens afterwards. Then it asks for my workbench disk. Using the workbench install disk, with HDtoolbox, it stops at the first screen saying checking scsi.device address 0 unit 0, and slowly moves to each unit as if it can't find anything.

For the CF card, the red light comes on but nothing else happens. Same problem with hdtoolbox but it freezes instead of doing anything.

Update:

I removed my motherboard from the case and the metal shield to get a better look and to my surprise it looks like this mb has been worked on from the factory. It looks like it was repaired before I even brought it.



I checked R971 and it seems ok close to 5k ohms, I can't seem to find R715, R715x and R715y anywhere. I only see R715A and C on that board.

If R715 A is the same as R715 x on the schematic and supposed to be also 4.7k ohms then it may be the problem, it is much lower right now. usually happens if the carbon resistor is shorting, but I can't remember, its been a while. When it burns all the way through it is usually open.

.... hmmm actually thinking about it... R715A and C are probably ok, it is R971 that may be bad, I need to unsolder it and check it again, my memory is coming back and the more a resistor is burned, the higher the resistance. It seems like R971 may be the one that is failing. That resistor should be the one protecting from excess current.

[Cubemon]

My CF adapter had a solder blob that connected two pins on the IDE connector. I'm lucky it didn't damage my Amiga, but it killed a 486 laptop I used for 64HDD with an X1541 cable.

The adapter itself worked fine (and is still installed in my A1200), when I removed the short.

But check the adapter before you connect it again!

[MoonDragn]

Originally Posted by Cubemon

My CF adapter had a solder blob that connected two pins on the IDE connector. I'm lucky it didn't damage my Amiga, but it killed a 486 laptop I used for 64HDD with an X1541 cable.

The adapter itself worked fine (and is still installed in my A1200), when I removed the short.

But check the adapter before you connect it again!

No, that particular adapter is fried. It had a protection circuit on it which is what saved the CF card. Luckily I had brought 2 other ones so I can just use one of those.

[indigolemon]

Have you checked for burnt traces on the underside of the A1200 mainboard?

[MoonDragn]

Originally Posted by indigolemon

Have you checked for burnt traces on the underside of the A1200 mainboard?

No, I have not. I was waiting for my ifixit tools to show up (arrived today) so that I could unscrew the back screws to remove the bottom shield.

[MoonDragn]

I analyzed the CF adapter card where the burn component is and it looks like it was connected to pin 39 which should have been the power to the LED.

The component must have been part of the driver circuit for the LED on the CF adapter.

I was thinking the burnt component was causing the failure of the IDE, but maybe it was unrelated.

Assuming I somehow flipped the cable, then the voltage from the LED would have been applied to pin 6 instead of pin 39... but that should not damage anything since it would have been one of the data lines for the CF card which should be able to withstand a vcc signal. Something else is causing the malfunction.

Here is the back of the Motherboard... Doesn't look like anything was damaged. The pins even look like they are in good condition. Going to have to do continuity tests...

[jlin_au]

The Amiga PCB explorer tool (https://www.amigapcb.org/index.php) for the Amiga 1200 rev 1D.1 board might be of use here. Please note that your board is marked as a rev 1D board.

Some of the extra yellow wires and added components may be Factory installed fixes to make the rev 1D board work (see the lo-res and hi-res [links at bottom] rev 1D motherboard pictures on https://bigbookofamigahardware.com/b...uct.aspx?id=13)

Amiga 1200 rev 1D circuit is available under https://www.amigawiki.org/dnl/schematics/A1200_R1.pdf .

If the CF adapter IDE cable had been plugged in backwards and power was applied, motherboard 5V power would have been applied as follows:
a) directly from pins 41 and 42 to the CF adapter IDE pins 4 (data line 16) and 3 (data line 31).
b) indirectly via the 4.7k resistor R971 from pin 44 to the CF adapter IDE pin 1 (/reset signal). The resistor would limit the current here to about 1 milliamperes max.
Note - Motherboard IDE pins 41, 42, and 44 are the only lines connected passively to a 5V supply.

The other motherboard IDE pins are:
a) directly connected to Ground (0V), pins 2, 19, 22, 24, 26, 30, 40, and 43.
b) connected to logic level input/output lines with limited current source/sink capacity
c) not connected at all (isolated)

Warning - from your pictures, your 1200 Motherboard has an unusual Clock port connector. The pin header on port P9B has all 40 pins (1 thru 40) populated. A normal clock port only has a 22 pin header installed over the rightmost pins 19 thru 40; pins 1 thru 18 on P9B are normally empty.

The extra header pins in P9B pins 1 thru 18 may be cause issue with using/;
1) a standard clock port connector lead later as the extra header pins 16 thru 18 on the left of 19 and 20 may physically block the insertion of the clock port cable header.
2) an Elbox FASTATA 1200 MK-V IDE CF/SATA adapter board as the unexpected extra header pins 1 thru 18 on the left may physically block the insertion of the main FASTATA board into the 1200 motherboard's ROM sockets U6B and U6A as the extra pins may touch the FastATA's PCB first and may also short to tracks/components on the FASTATA PCB.

[MoonDragn]

Thanks for the Info! That is kind of strange about the clock port! I never even noticed. Maybe it was related to the factory repair?

I know that 5V directly to the two data lines would not cause any issue because when you get a "1" signal on the line, it is equivalent to 5v anyway.

The Resistor in R971 is suspect since it has more resistance than any of the other 4.7k resistors on the board. I still have to get around to unsoldering it after I finish checking continuity.

The more I look at it, the likelihood that the Gayle is damaged is slim. Which is puzzling me why it is not working. I have a feeling it is related to either the _reset or the ide_irqs.

I can hear the motor running on the HDD so the +12 is fine. I can see the light on the cf card working so the LED drive voltage is still fine. That would mean either a blown resistor or a broken track somewhere not noticable. But the amount of current flowing through should not have been enough to burn a track.

[jlin_au]

A 2.5" IDE HDD usually normally has a special 44 pin IDE connector that adds 4 extra pins to the standard 40 pin IDE pinout. The extra pins 41 and 42 supply 5V to power the 2.5" IDE HDD from just the 44 pin IDE connection. The 2.5" IDE is normally only powered by 5V.

Can you provide pictures of the suspect special IDE cable you used? It may tel us what was wrong.

I have a cable that has a 44pin socket that plugs into the motherboard IDE port and then the 2.5" IDE HDD before terminating as a normal 40 pin IDE socket for a 3.5" IDE HDD or an IDE CDROM drive. I have to power the IDE device on the 40pin IDE connector via a separate power connection. When two IDE devices are on the cable one needs to be set as an IDE master (usually the 2.5" IDE HDD) while the second is set as an IDE slave. To access the second drive you need additional software like IDEfix97.

[MoonDragn]

Ahh you're right, the motor is on the +5 for 2.5 inch drives. That means there should not be any issues with the vcc. I can't think of anything else though. Everything seems to be fine, continuity, chip pins don't seem to be going to ground so probably no shorts. I am using the old cable that was working in there which doesn't make a difference so probably not the cable. The drive is on master (no jumpers)

The drive was originally working with the old cable, the CF card was originally working with the old cable. I had the 2 cf cards plugged in as master/slave on the new cable before I started smelling the burning smell from one card. The other card was also working with the old cable, in fact, better because the 2nd card was making the HDD light go on and off when the card was being read/written to. The first card always had a solid hdd light. The original 2.5 inch had the blinking hdd lights too. The burnt card was the card with the solid hdd light which was always on.

Here is the new cable:

[jlin_au]

Looks like a straight thru 44 pin IDE cable. Did you have two identical 44 pin IDE to CF card adapters on the cable? Was one adapter set to Master and the second to be Slave?

If they were non-identical adapters or badly designed, it's possible that the HDD LED driver circuit on the first adapter was incompatible with the HDD LED driver on the second adapter as they would have a common connection via pin 39 on the IDE port connection. E.g. one driver might have been driving pin 39 to 5V while the other was driving it to 0V; a short from 5V to 0V! A proper circuit design would have the HDD LED signal on IDE pin 39 being driven via an open collector circuit on both cards to 0V as required and being allowed to float to the normal bias voltage on pin 39 otherwise.

Check the following resistors have the correct measured resistances:

• R715(A/C) 4.7K AA-Gayle-R5 pin 12 _IDE_IRQ other end connects to 0V
• R715(C/A) 10K AA-Gayle-R5 pin 5 CC_RESET other end connects to 0V
• R971 4.7K IDE connector CN16 pin 44 one end connects to 5V
• R631(?) 10K IDE connector pin 39 _IDE_LED one end connects to 5V near transistor Q631
• R632(?) 4.7K IDE connector pin 39 _IDE_LED one end connects to Q631 base near transistor Q631

[MoonDragn]

Yeah the two CF cards were not identical. One had a transistor drive circuit while the other one just had a resistor. The one with the transistor drive has one transistor fried.

I check the resistors but without taking them out of the circuit and with my cheapie radio shack analog meter I can't really get exact readings. They all read between 3k and 10k. I don't think they are the issue though.

The HD LED on the keyboard does work when first powering up so that indicates that circuit is not damaged near Q631/632.

Since the led on the CF card that is not fried lights up, that leads me to believe everything is fine from that side too.

I think the problem has to be related to pin 37 and 38 ide that is connected to IDE_CS1 and IDE_CS2 since it is not sensing the drives.

[jlin_au]

IDE_CS1 and IDE_CS2 are cable selects generated (active low signals?) by AA-Gayle-R5.

Following links may be useful:
https://www.informit.com/articles/ar...28834&seqNum=3
http://wfcache.advantech.com/www/emb...ide_V0%201.pdf
http://www.interfacebus.com/Design_Connector_IDE.html

[MoonDragn]

Thanks! those are some of the same links I've been looking at. I finally got my Oscilloscope today with a digital logic analyzer I'm going to look at the signals when I get some free time... tax time

Originally Posted by jlin_au

IDE_CS1 and IDE_CS2 are cable selects generated (active low signals?) by AA-Gayle-R5.

Following links may be useful:
https://www.informit.com/articles/ar...28834&seqNum=3
http://wfcache.advantech.com/www/emb...ide_V0%201.pdf
http://www.interfacebus.com/Design_Connector_IDE.html