PDA

View Full Version : P&T Disk Not Ready



hexsane
July 3rd, 2009, 03:20 AM
On a TRS-80 Model II using P&T when I try to access disk b: I'm getting a not ready after the drive is selected. Drive a: is working fine and if I switch them around (either on the cable or changing the DSx jumpers on the drives) it gives me the same error?

Am I not doing something? I've selected the 2FLOPPY module and I see the light come on when the drive is selected.

-Matt

Chuck(G)
July 3rd, 2009, 11:12 AM
Have you checked your cable? In particular, have you checked pin 22 (ready)? Unlike later 5.25" TRS-80s, the Model II needs a ready signal from the drive.

(Disclaimer: I've got a Model 16, not a II, but it's pretty much the same on the Z80 side).

hexsane
July 3rd, 2009, 11:43 AM
Oops. Forgot to mention. I'm using 5.25" drives and I have Ready grounded (always ready). I have TEAC FD-55GFR drives but even with the RY jumper set the controller isn't accepting the Ready from the drive. This has worked fine with a single drive and works with either drive as 0.

-Matt

Chuck(G)
July 3rd, 2009, 01:09 PM
Oops. Forgot to mention. I'm using 5.25" drives and I have Ready grounded (always ready). I have TEAC FD-55GFR drives but even with the RY jumper set the controller isn't accepting the Ready from the drive. This has worked fine with a single drive and works with either drive as 0.

Does the P&T work with 8" drives? Have you tried any other CP/M, say, Aton with your Model II? Let's try to determine if it's a software misconfiguration or your drive setup that's at fault.

Oh, one other thing--when you select the second drive, does the disk spin? (Stupid question, I know, but I have to ask!)

hexsane
July 3rd, 2009, 02:50 PM
Does the P&T work with 8" drives? Have you tried any other CP/M, say, Aton with your Model II? Let's try to determine if it's a software misconfiguration or your drive setup that's at fault.

Oh, one other thing--when you select the second drive, does the disk spin? (Stupid question, I know, but I have to ask!)

I'll see what I can find on the IMD site. I have the drives tied to always spin when a disk is inserted and wait a second before attempting to access. I don't have any 8" media so I have to use the 5.25" drives.

-Matt

hexsane
July 3rd, 2009, 04:50 PM
TRSDOS isn't seeing it properly either so something else may be wrong. I'm thinking termination.

MikeS
July 3rd, 2009, 04:55 PM
I don't have any 8" media so I have to use the 5.25" drives.

-Matt
---
Want some?

Chuck(G)
July 3rd, 2009, 05:33 PM
TRSDOS isn't seeing it properly either so something else may be wrong. I'm thinking termination.

That could be a problem. The second drive should be terminated--I believe the Model II is rigged for standard 150 ohm pullups.

hexsane
July 3rd, 2009, 05:49 PM
That could be a problem. The second drive should be terminated--I believe the Model II is rigged for standard 150 ohm pullups.

I don't have the terminator pack on the external connector. I have it terminated internally properly. I need a pinout of the external connector so I can hack up a terminator.

-Matt

hexsane
July 3rd, 2009, 05:51 PM
---
Want some?

I have a total of 1 8" drive :) As long as I can attach 5" drives to 8" controllers and make system disks with IMD I think I'll be ok.

-Matt

Chuck(G)
July 3rd, 2009, 11:24 PM
I don't have the terminator pack on the external connector. I have it terminated internally properly. I need a pinout of the external connector so I can hack up a terminator.

Going back to your earlier post, you don't need to terminate the 55GFRs--they have the high-resistance pullups.

I'm assuming that your cable is "flat" without the PC "twist" business and that your drive selects are DS0 and DS1 respectively.


I wonder if the controller's not seeing an index signal from the drive. If you've got a logic probe or a scope, look for a signal on the index line at the Mod II main board connection. The drive may be providing it but it's not getting through. While you're at it, check the "read data" line too.

hexsane
July 3rd, 2009, 11:33 PM
I think I have discovered the source of my insanity (or at least this part of it) from the schematic DS0 only works internally DS1-DS3 are wired externally. What I need is DS0 and DS1 to be both internal or both external.

I could wire a second cable and connect DS1 to the external bus if there isn't an easier way. :)

-Matt

hexsane
July 4th, 2009, 01:11 AM
Making a second cable for the external port was the solution. In theory the controller can be configured for 2 internal mini-floppy drives but no amount of coaxing from me made this happen. Now to finish mounting the drives. :)

Chuck(G)
July 4th, 2009, 10:43 AM
That doesn't figure--lots of Model IIs and 16s have 2 internal drives. If I look at the schematics for my Model 16 with 2 internal 8" drives (Tandon 848-2s), it shows that J1 coming off the printer-floppy board has all 4 drive selects available on it.
(Dwg. 8000042),


Are you saying that the Model II uses something different?

hexsane
July 4th, 2009, 02:23 PM
http://www.pestingers.net/PDFs/Other_computers/MODII_16_TRM_FDC_REV.pdf

This is my controller. If you have one that is properly set for 2 internal drives I would love to know where to put the jumpers. :)

-Matt

Chuck(G)
July 4th, 2009, 04:07 PM
I'll do some grunting and have a look at my system. It might be that the Model 16 uses a somewhat different setup.

But have you tried jumpering H to F and S to T to get 2 internal drives to work? The schematic looks like that should.

hexsane
July 4th, 2009, 04:14 PM
Yes I did that and it responded the same. It looks like that should work but it didn't on my controller.

-Matt

Chuck(G)
July 4th, 2009, 07:01 PM
Okay, I pulled the floppy-printer card out of the model 16. Here's what I've got for jumper settings, going from left-to-right on the card:

L-M
P-Q
W-X
S-T
A-B
J-K
F-H

Internal floppies are connected to J0.

hexsane
July 4th, 2009, 08:03 PM
I can't find a W-X on my card.

F-H:
Is your board layout like
F
G
H

And are F G and H all tied together or just F H?

I'll take a picture of my card for comparison purposes when I get a chance.

-Matt

hexsane
July 4th, 2009, 08:41 PM
http://vintagemashups.net/pics/miifdcp.jpg
http://vintagemashups.net/pics/miifdcpj.jpg

RED: LMN & PQR
GREEN: STU & ABC
BLUE: FGH
YELLOW: IJK

-Matt

Chuck(G)
July 4th, 2009, 08:44 PM
The F-H jumper pads are F H G, with H in the middle.

Here's a photo of my card (http://www.sydex.com/temp/16fdc.jpg), somewhat enhanced so you can pick out the jumpers. It could be that we're working with two different card versions.

hexsane
July 4th, 2009, 09:01 PM
You have a newer cards. Your silk screen is different. I'll go with the settings as they are on your card. Are there any more jump wires on the other side of your card? (referring to the yellow wire near the ABC and STU jumpers).

Never mind. The WXY jumper set isn't even layed out on my card. I was hoping for unlabeled pins but the pins are not even there.

-Matt

Chuck(G)
July 4th, 2009, 09:39 PM
As closely as I can tell, all that you need to do is to make sure that the drivers fro the internal floppy connector are enabled for both drives. That should be fairly straightforward unless your card is very different from the schematic.

No, there are no wire jumpers on the back side of the card. OTOH, since I have a field-modified 16 (not a 16B), the CPU card has lots of added wires (to run Xenix).

hexsane
July 4th, 2009, 09:59 PM
Setting it up as you have it (excluding the WX as it doesn't exist on my card) it selects the drive and hangs. So there is a large enough difference in the cards to prevent it from working properly. You have some missing traces, additional traces (what are corrections on my board), a jumper set (WXY) and the yellow wire. It seems the newer models (12 and 16) have a revised FDC+P.

-Matt