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VERY fiddly hack. SMD resistors are a real pain to work with.Get yourrself a few spare resistors of the same value. You are better off sacrificing the component, and concentrate on keeping the solder pads intact. Practice on a scrap electronics board before doing the mod.The first stage is the hardest. The track cut is the next hardest.The good news is, your board has all the same marked connectors (DS0, DS1, S6) and the other pins (IC pin 1, floppy connector pins 2 and 34). So it should work.Surgical scalpel recommended for the track cuts - and doing SMD board work with a standard soldering iron is a real test of skill.A magnifying glass is better than nothing, but pros use optical zoom gear and similar nicer tools.
With my soldering skills, this is the way I do it:http://amigakit.leamancomputing.com/catalog/product_info.php?cPath=28&products_id=294
If, on the other hand, you want to permanently convert a random PC floppy drive into an Amiga one, just implement the cable signal changes directly onto the drive.For ID fixing, move the DS1 jumper (0 Ohm "resistor") to the DS0 position.For DISKCHANGE fixing, backtrack from pin#34 and see which pin of the square FDC controller chip connects to it (verify with a continuity test). This is where DISKCHANGE is produced on the controller.Cut the traces right behind pin#34 and pin#2 (so that they connect to nothing) and solder a wire from the FDC controller pin you just found to pin#2. This routes DISKCHANGE to the otherwise isolated pin#2.Solder a diode between pin#8 and the otherwise isolated pin#34 (cathode on pin#8, anode on pin#34). This imitates (*) READY on pin#34, and the conversion is complete (**).(*) If you want a true READY signal, you'll have to find which pin on the square FDC controller it's produced. The READY signal will be steady at around +5 V when no disk is in the drive (motor idle) and will drop to 0 V about half a second after a disk has been inserted (motor at full speed).Once the READY pin on the controller chip has been identified, you can connect it directly to the (otherwise isolated) pin#34 and skip the diode altogether.(**) You can also fix the HD detection switch permanently to the DD position, so the drive behaves as a DD drive at all times.
Cut the traces right behind pin#34 and pin#2 (so that they connect to nothing) and solder a wire from the FDC controller pin you just found to pin#2. This routes DISKCHANGE to the otherwise isolated pin#2.
That would be pin 2
Alright, if you don't believe what I say, re-read the guide at http://elgensrepairs.blogspot.co.uk/...5-fdd-for.html and tell me where exactly pin 4 is mentioned.So? If it wasn't connected to the IC, would there even be a point in saying "cut the trace" ? The very goal is totally *isolating* this pin from whatever false pin on the IC it may currently be connected to and then routing DISKCHANGE onto it.
@RiPThe instructions I posted are generic and can be applied to any drive. I can't possibly know what signal is enabled by jumper S6 or S-anything on your specific drive, or what possibly obscure and non-standard connections some pins may have.Hence the "dictator" instructions: either you follow them to the letter and ensure a specific behaviour for the drive, or you end up with a possibly unpredictable result.To sum up:0. ID jumper must be set for DS01. pins 2 and 34 must be perfectly isolated (if necessary, by cutting traces)2. DISKCHANGE (from the IC) must be routed to pin23. READY (from the IC) must be routed to pin34. If no READY exists or is tough to discover, you can alternatively do the pins 8-34 diode trick to imitate it.
(*) If you want a true READY signal, you'll have to find which pin on the square FDC controller it's produced. The READY signal will be steady at around +5 V when no disk is in the drive (motor idle) and will drop to 0 V about half a second after a disk has been inserted (motor at full speed).Once the READY pin on the controller chip has been identified, you can connect it directly to the (otherwise isolated) pin#34 and skip the diode altogether.
