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Help Make a Teac FD-55BV work the same as an Epson SD-521

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KLund1

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I have a particular system that will boot perfectly with a Epson SD-521. But I get nothing with a Teac FD-55BV.
When first powered the Teac will spin a second, and move the head back to zero. but nothing else. But this is normal at power up for almost any drive.
I have moved the DS jumper from O to 1, nothing. I have used both straight through and twisted ends of the known good ribbon cable, No change.
The Epson is set to 0 and has no other jumpers.
The Teac has lots of jumpers so I think it just a matter of where to put jumpers, but I have no idea which ones. This particular Teac is a 06-U sub version. I also have a Teac 55BR 102-V, and 55GRF 159-US.
I can find the Teac jumper settings wedbite pages, But I do not understand the particular vocab and abbreviations.
Any suggestions out there?
Thansk
 
Since you did mention the system you're trying to use it with, I'll give the default setting for a 55BV on DS0:

Jumpers only on the following: DS0, RY, FG, E2. All other straps off. Be sure to make sure that drive termination is correct, if this is the last drive on a series, or if it is the only one.
 
Thanks Chuck(G), I appreciate the help.
There is no E2 that I can find on this drive's PCB, only E0, and E1. E0 had a jumper and I removed it. I removed XT jumper and put that on only pins of DCRY (the side of RY) But now there is no spin or LED on power up. Termination appears to be installed in RA1, it is labeled IAM E3317
 
There are several revisions of the Teac FD55 drive. Try this: add a jumper to ML and see if the motor spins then.
It would be useful to know what system you're using this with. Absent that, one can only guess.
 
Thanks again. The ML pin jumped did not make any difference. No spin. I attached a pic of the PCB
You will most likely not know the system. It is an Atari 1450XLD TONG board. There are only a handful known to exist. The holy grail in Atari land. The Apple I's were mass produced compared to all the 1400 series computers.
I'm trying to get it fully working (two drives) and cased, before I show it to the Atari world. There are probably not too many Atari people reading this particular forum, so I thought I'd start here to get the second drive working. Epson SD-521 are hard to find. Teac's are easy to get. The BV is lower power and should be able to run off the board header. Though I'm using a ATX PSU for testing the FD for this thread tests, just to be safe. The Epson did run connected to the board.
 

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Do you have a 'scope or logic probe available? Better yet, a schematic of the device?
This Vogons post has me wondering if your Epson drive isn't an unconventionally-configured one.
 
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I have both, but not very good at all with the scope, and always seem to set the switched wrong on the probe. The auto button on teh scope is very helpful.
I attached the 1450 schismatic section for FD. The PDF was too large so I change to jpg. If there is something you cant read let me know. I can read it back or possibly email.
 

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I'd sanity test this floppy drive with a normal PC first to ensure it is working properly.

What was the source of the epson drive? Was it used in a PC before and were there any changes made to it to make it work with this device? If it was and no changes made, then in theory, the teac should work with the default jumper settings.

Glancing at the schematic, I see four drive select pins and a motor select. So the controller is a Shugart interface rather than IBM. That means the drive would use a flat cable, and should be jumpered as the first drive, rather than IBM PCs standard of jumpering as second.
 
Personally, I'd start by plugging the drive into the power connector and leaving the signal connector out. All drive inputs are high-negative, so you activate them by grounding them. Start with the MOTOR pin--the spindle should turn the moment this pin is grounded. Next, try the drive select pins. The LED should go on when you hit the one that's jumpered. And so on...

Could be the case that the Atari's PSU isn't supplying +12 volts.
 
Thanks for the replies.
The Teac worked just fine with my 486 test board. It would boot/read/write/format 360kb disks normally. I used this drive a lot about 4 months ago while testing many 8088 to 486 boards.
The source of the Epson drive in unknown, and unknown about changes to it, if any. There is nothing obvious. It looks 'stock' to me. All the solder joints look the same. It may have come from atari. Drives that have the same push button eject is shown in several Atari produced pictures of this computer working, But there are other pictures with a leaver type drive working. There is no 'official' drive for this system.
The Atari power brick supplies +12v. But I'm using an outside ATX PSU for testing this drive for now. The Atari PSU is new, about 3-4 yerars old, not used, and I put a correct connector to the system.
 
Okay, with the drive connected to the PSU and nothing else, does the motor start when pin 16 of the drive connector is grounded? Does the LED come on when pin 10 is grounded?
 
That makes sense and conforms to the jumper settings. Now, the next question is "exactly what signals does your Atari send out to select a drive and turn on the motor?
 
The attached schismatic above might help with that. I can barely read them. I do not know the abbreviations or their meanings. The board uses a 'standard' WD2797PL-02 controller, and the Epson looks standard too.
 
The schematic is perfectly readable. It supports MOTOR ON on pin 16, via the output of the 8155/7406 combination.
Similarly, DS0 is controlled by Pin 16 (although on the schematic, it's labeled as DS1 (some drives use DS0-DS3, others use DS1-DS4--there is no standard for the labeling). If you have a DMM or logic probe, you can check both those pins when the unit attempts to access the floppy.
 
Sorry for the delay. Been busy with other stuff. Major discovery below.
Pin 16 is low all the time using my logic probe. I could only find the 7406 on the board. No 8155, 8040, or 8050.
So I did a pin-out/tone of all the FD connector pins. And they do not go to most of the places shown on the schismatic.
Left number is FD connector pin
34-4,5 74LS00 U9
32-10 7406 U4
30-27 WD2797 U19
28-36 WD2797 U19
26-34 WD2797 U19
24-8 7406 U4
22-6 7406 U4
20-4 7406 U4
18-2 7406 U4
16-12 7406 U4
14-10 7407 U5
12-8 7407 U5
10-12 7407 U5
8-35 WD2797 U19
6-2 7407 U5
4 –null
2 –null

Something else major. I have been using my ATX psu for testing. Just to check I connected the Epson back the the ATX and MB. No joy. But connected Epson to MB power and it booted normally from disk. Then connected Teac to MB power. Nothing. But we might need to change jumpers with this new info.
What do you think.
ps the lower left of the schematic is the FD power connector circuit. J13 is the connector and that show on the MB stencil.
 
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Connect the Teac and then see if you have +12 at the drive power supply connector. If pin 16 is low all the time, then the motor should be spinning, regardless of the state of other pins. Something doesn't make sense.
 
When the board boots without a disk inserted, there is a message saying, "Please Insert Disk and Close Drive Latch"
While that message is on screen, the logic probe on the FD connector pins show: with no drive connected
2,4,6 -null
8 high
10 low
12, 14 null
16 low
18,20,22,24 null
26,28,30 high
32 null
34 high

With the Teac drive connected and the board is trying to boot from it with no motor spin; (showing 'boot error' on screen) the pins show
2 null
4 high
6,8,10 null
12,14,16,18,20 high
22,24 null
26 high
28,30 null
32, 34 high

New development: It works!!
I went back to basics. This is getting too complicated (but interesting). Start simple. I pulled the WD chip out, cleaned the legs, and the socket. They looked good already. But spayed in some deoxit, and reseated it and tried a boot. and the Teac Booted !!!! wwwwooohooooo !!!!
Tested with the Epson and it still works, But the Teac is about a second faster.

Many thanks !! for all the help!!
 
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