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TK50 various questions

Johnny Bilquist created "patch 448" which supports non-DEC MSCP devices (e.g. CMD) - https://groups.google.com/forum/#!topic/vmsnet.pdp-11/S9ZR_C_swg0

I don't remember if Don had patched Zeke up to that level but I'm sure he'll check in here shortly.

Jack

Patch 441 was sufficient to resolve the booting issues I had with CMD CQD-200/220 controllers.

Code:
Subject: libvmf,cpp,rauboot,mkstr(1) fixes, ld feature (#441)
Index:	usr.lib/libvmf,lib/cpp,sys/mdec/rauboot.s,... 2.11BSD

Description:
	1. The libvmf (virtual memory using tmp files) routines could crash
	   or hang an application if too many locked segments were requested.

	2. The C preprocessor (cpp) had a memory leak which could cause it
	   to run out of memory _and_ also failed to check the return
	   status of calloc() which would cause cpp to fail ungracefully.

	3. The MSCP bootblock would not work with a CMD CQD220 adaptor due
	   to the bootblock relying on the (undocumented?) behaviour of DEC
	   adaptors.

	4. In the mkstr(1) manpage the usage example given used lseek(2)
	   incorrectly.

	5. The linker (ld) does not accept the '-g' flag which on other
	   systems says to retain debuggin symbols.

	6. creat() is no longer a system call, thus it is an error to
	   have creat(2) instead of creat(3).
 
More questions than answers! The TK-50 drive assembly arrived last night and although only had about fifteen minutes to examine it the unit appears to be a TK-50Z-FA standalone drive with an internal SCSI card. I have a M-7546 card on the way and am assuming that the 7546 has a 26 pin port that connects directly to the TK-50 drive so going to assume that if I put together a 26 pin to 26 pin cable the card and drive will work and all I will have to do is disconnect the SCSI card in the drive assembly? If I can get the card and drive to work together will then start thinking about going to an SCSI card on the 11/23 and trying a SCSI connection between the drive and the computer. The end goal is to get a working SCSI port on the system. Going to assume that the card direct to the drive will be good in RT-11 using MU but wonder what will happen if I try to use SCSI in-between the drive and the system. Still looking for TK-50 tapes also, there are a lot of ten over on EBay but hate to spend more on the tapes than any other part of the project.
 
I think that should work, just connect one end of the ribbon cable to the drive itself and the other end to the TQK50 controller. I was thinking of putting my TK50 in an old external DLT case that I have so I can move it between systems with ease.
 
I think that should work, just connect one end of the ribbon cable to the drive itself and the other end to the TQK50 controller. I was thinking of putting my TK50 in an old external DLT case that I have so I can move it between systems with ease.

My only experience with SCSI was putting an HP Surestore DAT 40x6 in my desktop tower. It required the SCSI chain be terminated. The 40x6 has two SCSI ports on the back much like an RL02 drive. The terminator went in the unused "output" port just like in an RL02 chain. Does the TK50 require a similar setup?
 
The TK-50 drive assembly arrived .... appears to be a TK-50Z-FA standalone drive with an internal SCSI card. ... assuming that the 7546 has a 26 pin port that connects directly to the TK-50 drive so going to assume that if I put together a 26 pin to 26 pin cable the card and drive will work and all I will have to do is disconnect the SCSI card in the drive assembly? ....
If it is any help:
My 7546 and TK50 connectors were not keyed. So I cabled the7546 as a 26 pin "red stripe to right" (when holding the M7546 card horizontally, components up and with with the "purple ears" closest to you), on the drive the red stripe was then was closest to the voltage connector on the drive.
 
The TK50 I have (a single drive - but no case) is "single end".

The cable comes from the contoller card and goes straight to a single connector on a single drive. I will need to check the BSD software to see if appears to support more than one drive on the one cable. Somehow I doubt the hardware has that option. There are no jumpers on the drive or board that select "drive 0/1" and/or terminators. However you can have two controller cards (at least) in the backplane and thus get two drives.
 
Figure the TK50Z-FA I have is the SCSI version of the TK50 drive for use with the VAX hardware. Just quick look at the drive reviled a TK-50 drive that has a 26 pin ribbon cable that connects to a card located just above it in the case that translates TK speak to SCSI and on the back of the case is the standard old school SCSI connectors. Use to work with SCSI a lot in the old days with graphic production system and nonlinear editing systems so have lots of cables and cards for PC systems and what I may try doing before trying to get this to work with the PDP-11 is set it up on a SCSI card on an old PC and try working it thru windows as an external drive. Just hope I saved the drivers for those old ISA cards. Eventually going to try to get everything working for the 11/23with the M-7546 connected with a 26 pin cable to the TK-50 directly first but also have an aftermarket SCSI card that fits in a Qbus system and then will try to get the SCSI port to work on the eleven. But that’s all after I get the TK-50 up and running first. Think I did find a source of tapes, just have to wait till I get home to log on and buy them. It looks like the plan is coming together. Deinceps in praeteritum!
 
The M-7546 I have has all the switches set to 0 (off) and only the first two jumpers as viewed from the front of the card in place. Was wondering if anyone else has a card and can tell me what the default setting for the switches are. Have the manual but have not found the default settings for the switches yet. I would like to have the address and vector set so this is MU 0 or 1. still waiting for the tapes to arrive but was able to clean up the drive and check the power supply, interesting to see that they have a load card to keep a respectable load on the power supply with a flock of resistors to end up with about three or four ohms on the five volt bus and twelve ohms on the twelve volt bus.
 
jumpers

jumpers

The M-7546 I have has all the switches set to 0 (off) and only the first two jumpers as viewed from the front of the card in place. Was wondering if anyone else has a card and can tell me what the default setting for the switches are. Have the manual but have not found the default settings for the switches yet. I would like to have the address and vector set so this is MU 0 or 1. still waiting for the tapes to arrive but was able to clean up the drive and check the power supply, interesting to see that they have a load card to keep a respectable load on the power supply with a flock of resistors to end up with about three or four ohms on the five volt bus and twelve ohms on the twelve volt bus.

Both my cards have the uppermost switch bank as zeroes - all switches are down/off.
The lower switch bank on 1 card is set to 0010 0000 (card 2 is in a live unit just now. I *THINK* it is 0110 0000)

The jumpers lower right are 11001010000
repeat 110 010 100 00 (reading Left to Right) My card

I have jumper between the connector and the oscilator also a jumoer to the left of the N82S105 and a jumper in place near pin 3 of the same chip.
I will get back to you with a link to the manual later. From memory I think the s/w sets up the vector and the card sets up the CSR. I will be back in 10.
 
Search for EK-0TK50-TM-001_TK50_Tape_Drive_Subsystem_Technical_Manual_Jul85.pdf
pages starting about 4-14 talks about the TK50 controller card. pages 4-20 covers setting up MU0 up to MU3

The other manual I found was EK-0TK50-TM-002_Jul86.pdf - see section 5. Very similar (if not identical?) information in that section to the earlier manual section 4.

Cleaning the unit. I now have three units running. In all case I followed the advice in this forum and dismanted and cleaned the tacho sensor on the rear roller.
Without that clean the drives oftne parked themselves with a furious flashing red light on the front of the drive.

I found it hard to get into the tacho on the newer drives. The ribbon-cable was hard to work with. IMHO do not try to remove the led/photo sensors from the plastic housing. They are glued in. Remove the carrier to get to the tacho. Take care, even a canned air-brush will visibly move/disturb the spokes on the tacho wheel.
Good luck
 
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Going to post this under Pentium section also being people there may have additional input. I have my TK-50 tape drive up and running, have tapes for it and the M-7546 card for the PDP-11/23 and am just in the process of getting that card set up and building up a long twenty six pin header cable to go between the drive and the controller. The TK-50(TK50Z-FA) is in a housing that also contains an internal SCSI controller that extends out to two old style SCSI connectors on the back of the drive. For use with the DEC will bypass the internal SCSI controller and just use the drives twenty six pin connection. But here is the question, if I install a SCSI card into an old PC running something like Windows 98 or XT what utility would I use under Windows for controlling an external tape drive? Have been under the impression that it will appear as an external drive under windows via the SCSI port and maybe just show up like an external hard drive or do I have to run something else to use the external tape system? Also have a copy of Windows NT if that would be better suited for doing this. The idea is at the end of the day having a drive that can work with the PDP-11 system under RT-11 and by changing the configuration also work under Windows? Or am I wasting my time because the file structure under the two operating systems is so different that although the drive may work tapes written in RT-11 cannot be read by Windows? Don’t intend to run programs, just be content to transfer them from DEC world to Windows world for distribution or sharing.
 
Why not go for a *nix on the PC?
I use a mixture of centos and ubuntu on an old old old adaptec card to access all sorts of SCSI devices. Seems to work great for me.
Good old "dd" and "mt weof" on a *nix can be coaxed to write just about any format of tape you want.
 
My brain is too small to accommodate new technology! Will look at that as a future project being now days I am locked into Windows, DOS and RT-11. Not a programing person just a hardware hack. Downloaded the “Microsystems Options” manual and have to say that’s quite the book. Just slapped all the junk together last night and was not getting much love from the drive but hope to get out to the shop tonight and look at things like addresses and cable connections. The drive would load, read the tape and then move it around and work the head up and down when using the SCSI controller that was in the external drive chassis but last night with the drive connected directly to the 7546 card other than loading the tape nothing else happened. But it was late and did not have that much time to beat on it.
 
All is good - That behaviour on the 7546 card is the same as mine.
If you press and release the red button 4 times in quick succession the tape may run a little bit in.
The head climb and fall is part of the first access to the drive. I guess the scsi board does something to read the tape on load?

dir mu0: next??
 
New Issues! I am running RT-11 version 5.03 and the instructions for the TK-50 say it has to be RT-11 version 5.4 minimum. Any comments?
 
New Issues! I am running RT-11 version 5.03 and the instructions for the TK-50 say it has to be RT-11 version 5.4 minimum. Any comments?

AFAIK, that's correct. In fact, there are some indications that the TMSCP drivers weren't really stable in RT-11 until 5.7.
 
Looks like 5.4 is the magic number, things like the TK-50 , RA-80 and 81 and a lot of other stuff did not happen until 5.4 Also wonder if 16 bit 11/23 hardware is up to the task of running anything like 5.4 and above?
 
I got caught with the default "bootstrap" of rt-11 on the later system like ?5.7? needing sep I/D.
There was some magic I run to run a "single user" and "non sepid" at startup. If you dont know what I am muttering about, tell me and - when I get home - I can get out my notes and remind myself of the files and commands that I had to run to get a book on an 11/23 board.
 
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