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Model II,12,16,16B,6000 8" to 5.25 Inch floppy adapter cable 50 pin to 34 pin

Looking at the few 8" drive manuals I have, those things look like they're configurable almost to the point of "use any pin for whatever you feel like". I tried to cover what I thought are the most common configurations with this little board, but I'll welcome input about any configuration features that I missed which are common enough that they should get special support on this board.

Beware of feature creep...killer of many noble projects. Thanks for taking this on, Mark. A thorough treatment of this topic was sorely needed.
 
Well partial success. I still need to hook the internal drive up to the external connector and set internal drive id to DS0.

Mark: I used your diagram to build but did not add the motor jumpers as you can see in the pics.

The Jumper E40-41 shorted is what got it going.

Oh and the space bar does work!

Making progress!!!!
 

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Ok for some odd reasons TRSDOS boots up fine boot whenever I try to execute a command I get error 31 must be bad disks. But all 4 of them I have?
Oh Well CP/M works and so does LS-DOS.

Ok drives I tested IBM YD-380 jumper set to 0. Teac FD-55GFR Jumper in RY (ready) position and drive set to 0 also. I have a copal I am going to try but they soldered in the drive select jumper. Will have to perform surgery.

Regarding the IBM drive It seems like it doesn't matter if the drive has the a ready jumper or not. Just works
 
Ok for some odd reasons TRSDOS boots up fine boot whenever I try to execute a command I get error 31 must be bad disks. But all 4 of them I have?
Oh Well CP/M works and so does LS-DOS.

Ok drives I tested IBM YD-380 jumper set to 0. Teac FD-55GFR Jumper in RY (ready) position and drive set to 0 also. I have a copal I am going to try but they soldered in the drive select jumper. Will have to perform surgery.

Regarding the IBM drive It seems like it doesn't matter if the drive has the a ready jumper or not. Just works

Are you able to boot from the 5.25 drive?

Edit: Never mind. I see that you hooked up to the internal interface and set to drive 0 so you obviously are booting from the 5.25. Very nice!
 
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Which version of TRSDOS are you using? It's my understanding that versions before 2.0b assumed that you have the older drives in which the spindle motors spin constantly and a solenoid loads/unloads the heads as needed. Those earlier versions will have trouble with the newer slimline drives, which turn off their spindle motors when not in use, and then require some extra spin-up time when starting back up. I think that any 5.25" drive will also behave the same way. TRSDOS 2.0b adds support for drives which turn off their spindle motors.
 
Could be I will see if I can locate TRSDOS 2.0B.

Just as I note the 8" Tandon in mine is a TM-848E. And drive select DS1 is actually 0 and drive select DS2 is ID 1.

So I set the jumper on the 8" to be drive ID1. Seeing as though 0 does not work on the external connector.

So right now the 5.25 is hooked to the internal as drive 0 and the 8" is hooked to the external as Drive 1.

This configuration does work. I am currently copying LS-DOS 6.3.1 from the 5.25 to the 8". Yay building up a library of 8" disks.
 
If I recall correctly, I got an image of TRSDOS 2.0b from the system disk collections that are posted with ImageDisk.
 
the TDOS20B.IMD that is that archive is 2.0A As is the TDOS20A.imd. According to IMD when you do the write option see PIC.

So if anyone out there has TrsDos 2.0B IMD image let me know also TrsDos II 4.x as well. PM me with details
 

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That might just be a typo in the IMD comment, which is entered manually at the time the image is created. I'd try the image anyway to see if it works better. I'll try it myself when I get a chance, but that probably won't be until I get my adapter boards back and hook up my Lotharek emulator, in a week or two.
 
Booted image says its the A version. see Attached pic this is the so called B version booted. As you may notice it says A. (sorry for the angle) Would like to get the other 2 mentioned.
 

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Hmm, ok. I thought that I had tried that image file, but maybe my memory is faulty. I'll have to look to see if I have a 2.0B disk that I can image.
 
Appreciate it Mark! Do you have maybe TRSDOS II 4.x someplace? It supposedly has Hard disk drivers.

OK FYI to all the copal disk drive do not work. So the Teac and IBM do. Just an update.

I think tomorrow I will try some 3.5" drives and see how they work!
 
I found the original (but modified) TRSDOS 2.0b floppy that I think I previously used to boot up my Model 12. It took me a few tries to get my 12 to boot up, so hopefully the disk is still good. I don't think I'll get around to putting my Imagedisk system back together tonight because I'm pretty tired, but I'll try to image the disk sometime this week. It has some extraneous files on it from a previous owner, and I don't know if anything important is missing. But it displays the 2.0b version banner, it works with my Model 12's slimline drives, and it includes the BASIC interpreter. I'd still like to get an image of an unmodified original 2.0b distribution, but this will be a good start.

I don't have TRSDOS II 4.x yet. It's another thing I'd like to get my hands on. I really haven't done much with my big-boned TRS-80 machines yet, but your recent threads have been nudging my interest in getting around to it! Case in point: the floppy adapter board that I've had on my idea list for many months, and this thread nudged me into finally designing it. Thanks! :)
 
I don't have TRSDOS II 4.x yet. It's another thing I'd like to get my hands on. I really haven't done much with my big-boned TRS-80 machines yet, but your recent threads have been nudging my interest in getting around to it! Case in point: the floppy adapter board that I've had on my idea list for many months, and this thread nudged me into finally designing it. Thanks! :)
I have to stop being so lazy. I have both of these in my "collection". Have not imaged them ever though.
 
FYI on the prototype 8" to 5.25. When initially powering on with the 5.25 on the internal connector and jumpered as drive 0 the drive activity light will come on and stay on till a disk is inserted.

Not sure why this is happening. Most likely the in use signal. But it is not a big concern.

Also the motor only comes on initially then turns off. When data is requested of it of course the motor turns on sends data then motor turns off after a few seconds and the light stays off till there is more disk data activity. That is the kind of behavior that should be happening. That is how the 8" works as well.

So just thought I would mention this.

As for the motor on signal I wired pin 16 of the 34 pin to wire 18 of the 50 pin. So no jumpers for motor on are needed IMO.
 
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