nikola-wan
Veteran Member
While working on the 4052/4054 opcodes, I remembered that I had tried to recover a Motorola 6800 Disassembler program from an Applications Library - Interfacing T1 tape, but the tape was too damaged to recover that file in 2018.
Two years ago I had received several boxes of 4050 tapes from the estate of a Tektronix Sales Engineer - shipped to me by Kurt Rosenfeld who runs the TekWiki website: TekWiki
One of the boxes of tapes had labels "Applications Library Tape" 1 to 20!
Most of those tapes are labeled "MASTER TAPE" - meaning the one Tektronix used to make copies for users that submitted new programs.
I hoped that these tapes included ALL the user contributed programs listed in each issue of Tektronix Tekniques newsletters from 1975 for the 4051 and in 1979 including the second generation 4052 and 4054 computers!
No list of files was found with these tapes - and I had seen an article in the 1981 Tekniques Vol 5 No 3 - "Application Library Consolidation" that indicated Tektronix consolidated the 200 user contributed programs into 27 tapes with orderable Tektronix part numbers and like-subjects:
I believe the tapes in the estate were the original tape masters used to create the Application Library collections - which has an abstract catalog - where each abstract was originally published in a Tekniques newsletter:
Tek 4050 Series - Application Library Programs - Sept 1981
I then guessed that the estate tape numbers were based on the date the programs were submitted.
Since the MC6800 Disassembler Program was posted in the Tekniques V3N6 in September 1979, I guessed that I might start looking for this program in tape 11 out of the 20 tapes - since I imagined after the 1981 Application Library catalog introduction that there were no more separate MASTER TAPES.
I examined MASTER Tape 11 and of course the drive belt was broken.
I took the drive belt off one of my working 3M 6250 tapes and installed it on tape 11:
You can see some of the broken belt pieces in the bottom of the photo. Tape 11 broken drive belt was yellow, the broken Tape 16 drive belt was tape color - since the drive belts were actually rings stamped from the same plastic as the tape and formed into a ring at the factory.
I found Tape 11 had not been rewound - so before installing the good drive belt from the 6250 cartridge in the photo - I manually wound Tape 11 back near the beginning of the tape using one finger to provide tension on top of one reel while I used a wooden chopstick in my other hand to wind the other wheel. When I had the tape rewound near the beginning - I installed the good drive belt and adjusted the belt tension until it was snug - but not too tight and put the tape in my 4054A, typed 'TLIST' and got the name of the first file then MAG TAPE READ ERROR.
I then decided to pick a couple of file numbers to try to read and did 'FIND x' and 'CALL "HEADER' (4052A/4054A BASIC command) for files 3,4,10 and11 and saw this on the screen:
Since there is no real-time-clock standard on the 4050 computers - there is no date/time stamp in the tape header format.
I failed to get a hit on google searches for any of these names, so tried the TLIST command and got the file headers listed for the entire tape11!
I then searched google for Tektronix Tekniques "War at Sea" and found Tekniques V2N8 had an article on the Navy using 4051 to make a war at sea emulator - and they contributed the program to the Application Library!
The only indication of a date of this issue was on page 13 list of 4051 Graphic System Publications "up to December 1978.
I then guessed that the next tape I should try was Tape 16 and I got lucky! I moved the good drive belt from Tape 11 to Tape 16 after manually winding and rewinding the tape because part of the takeup reel tape had slipped down near the metal backplate - so I wound the tape onto the supply reel past that point then rewound near the beginning and then attached the good drive belt. Tape 16 had pieces of the broken drive belt stuck to the oxide side of the takeup reel and supply reel - so I spent some time carefully moving the tape over the guide posts to get most of the drive belt to fall off the tape. Those are the tiny fragments in the photo of the three tapes.
When I inserted Tape 16 and attempted to perform a TLIST I got the file1 header and then a MAG TAPE Error.
I then check the 4054A tape head - very dirty - cleaned the head with isopropyl alcohol on a long swab and tried TLIST again - SUCCESS!
File 3 header was "MC DIS" so I immediately hit the BREAK key to stop the TLIST.
I then performed a FIND 3, OLD, LIST and saw that I had found the MC6800 Disassembler Program!!
I ran the program once and selected tape file 4 for the data and the output listing was displayed on the CRT.
I wanted to save the File 4 data file to my Flash Drive - so I took the Flash Drive MicroSD with the saved disassembler program to my PC and added the ability to save the listing to a Flash Drive file and then reinstalled the MicroSD card into the Flash Drive and reran the program. I also knew from examining the program that A$ contained the HEX object code - so I wrote A$ to a new file on my Flash Drive.
Since my Flash Drive contains my TapeDump8b as file 8 in the ROOT directory, I had also created on my PC a AppLibrary folder on the Flash Drive with a file 1 and LAST file - I changed to that directory and typed MAKE @5:22,1000 which created 22 files of 1KB. The Flash Drive uses the FAT32 filesystem with large filename support. The Tektronix MAKE command creates a new file or files and the 4050 tape needs the MAKE filesize to be greater than program or data to be stored because the subsequent file prevents the 4050 from increasing the filesize later. The Flash Drive doesn't care about the MARKed filesize - it just reports the FAT32 filesize on demand.
I was able to recover the entire Tape 16 files with TapeDump8b - except for a MAG TAPE READ error on file 13.
I was able to restart my TapeDump starting with file 14 and captured the remaining program and data files.
Then I tried to FIND 13 and OLD - and it worked! So I then did a save of program file 13 - and after editing the file headers and ASCII program and DATA files from the single tape dump file - I will be able to post everything from Tape 16 to my github repository!
Here is the list of file headers on Tape 16. I added the full program name and which Tekniques newsletter contained the abstract:
Plus I will be posting the MC6800 to my repository - and likely adding it to my Flash Drive!
Two years ago I had received several boxes of 4050 tapes from the estate of a Tektronix Sales Engineer - shipped to me by Kurt Rosenfeld who runs the TekWiki website: TekWiki
One of the boxes of tapes had labels "Applications Library Tape" 1 to 20!
Most of those tapes are labeled "MASTER TAPE" - meaning the one Tektronix used to make copies for users that submitted new programs.
I hoped that these tapes included ALL the user contributed programs listed in each issue of Tektronix Tekniques newsletters from 1975 for the 4051 and in 1979 including the second generation 4052 and 4054 computers!
No list of files was found with these tapes - and I had seen an article in the 1981 Tekniques Vol 5 No 3 - "Application Library Consolidation" that indicated Tektronix consolidated the 200 user contributed programs into 27 tapes with orderable Tektronix part numbers and like-subjects:
I believe the tapes in the estate were the original tape masters used to create the Application Library collections - which has an abstract catalog - where each abstract was originally published in a Tekniques newsletter:
Tek 4050 Series - Application Library Programs - Sept 1981
I then guessed that the estate tape numbers were based on the date the programs were submitted.
Since the MC6800 Disassembler Program was posted in the Tekniques V3N6 in September 1979, I guessed that I might start looking for this program in tape 11 out of the 20 tapes - since I imagined after the 1981 Application Library catalog introduction that there were no more separate MASTER TAPES.
I examined MASTER Tape 11 and of course the drive belt was broken.
I took the drive belt off one of my working 3M 6250 tapes and installed it on tape 11:
You can see some of the broken belt pieces in the bottom of the photo. Tape 11 broken drive belt was yellow, the broken Tape 16 drive belt was tape color - since the drive belts were actually rings stamped from the same plastic as the tape and formed into a ring at the factory.
I found Tape 11 had not been rewound - so before installing the good drive belt from the 6250 cartridge in the photo - I manually wound Tape 11 back near the beginning of the tape using one finger to provide tension on top of one reel while I used a wooden chopstick in my other hand to wind the other wheel. When I had the tape rewound near the beginning - I installed the good drive belt and adjusted the belt tension until it was snug - but not too tight and put the tape in my 4054A, typed 'TLIST' and got the name of the first file then MAG TAPE READ ERROR.
I then decided to pick a couple of file numbers to try to read and did 'FIND x' and 'CALL "HEADER' (4052A/4054A BASIC command) for files 3,4,10 and11 and saw this on the screen:
Since there is no real-time-clock standard on the 4050 computers - there is no date/time stamp in the tape header format.
I failed to get a hit on google searches for any of these names, so tried the TLIST command and got the file headers listed for the entire tape11!
I then searched google for Tektronix Tekniques "War at Sea" and found Tekniques V2N8 had an article on the Navy using 4051 to make a war at sea emulator - and they contributed the program to the Application Library!
The only indication of a date of this issue was on page 13 list of 4051 Graphic System Publications "up to December 1978.
I then guessed that the next tape I should try was Tape 16 and I got lucky! I moved the good drive belt from Tape 11 to Tape 16 after manually winding and rewinding the tape because part of the takeup reel tape had slipped down near the metal backplate - so I wound the tape onto the supply reel past that point then rewound near the beginning and then attached the good drive belt. Tape 16 had pieces of the broken drive belt stuck to the oxide side of the takeup reel and supply reel - so I spent some time carefully moving the tape over the guide posts to get most of the drive belt to fall off the tape. Those are the tiny fragments in the photo of the three tapes.
When I inserted Tape 16 and attempted to perform a TLIST I got the file1 header and then a MAG TAPE Error.
I then check the 4054A tape head - very dirty - cleaned the head with isopropyl alcohol on a long swab and tried TLIST again - SUCCESS!
File 3 header was "MC DIS" so I immediately hit the BREAK key to stop the TLIST.
I then performed a FIND 3, OLD, LIST and saw that I had found the MC6800 Disassembler Program!!
I ran the program once and selected tape file 4 for the data and the output listing was displayed on the CRT.
I wanted to save the File 4 data file to my Flash Drive - so I took the Flash Drive MicroSD with the saved disassembler program to my PC and added the ability to save the listing to a Flash Drive file and then reinstalled the MicroSD card into the Flash Drive and reran the program. I also knew from examining the program that A$ contained the HEX object code - so I wrote A$ to a new file on my Flash Drive.
Since my Flash Drive contains my TapeDump8b as file 8 in the ROOT directory, I had also created on my PC a AppLibrary folder on the Flash Drive with a file 1 and LAST file - I changed to that directory and typed MAKE @5:22,1000 which created 22 files of 1KB. The Flash Drive uses the FAT32 filesystem with large filename support. The Tektronix MAKE command creates a new file or files and the 4050 tape needs the MAKE filesize to be greater than program or data to be stored because the subsequent file prevents the 4050 from increasing the filesize later. The Flash Drive doesn't care about the MARKed filesize - it just reports the FAT32 filesize on demand.
I was able to recover the entire Tape 16 files with TapeDump8b - except for a MAG TAPE READ error on file 13.
I was able to restart my TapeDump starting with file 14 and captured the remaining program and data files.
Then I tried to FIND 13 and OLD - and it worked! So I then did a save of program file 13 - and after editing the file headers and ASCII program and DATA files from the single tape dump file - I will be able to post everything from Tape 16 to my github repository!
Here is the list of file headers on Tape 16. I added the full program name and which Tekniques newsletter contained the abstract:
Code:
1 ASCII PROG /MANNING'S/ Tekniques V3N7 Manning's Equation Depth Flow
2 ASCII PROG /BABY CARD/ Tekniques V3N7 Baby Announcement Card
3 ASCII PROG /MC DIS / Tekniques V3N6 MC6800 Disassembler Program
4 ASCII DATA / " /
5 ASCII PROG /QUANTEX / Tekniques V3N7 Quantex DS-12 Interface
6 ASCII PROG /MASS STOR/ Tekniques V3N7 Mass Storage Management System
7 ASCII PROG /MASS DUP / Tekniques V3N6 4924 Mass Tape Duplication
8 ASCII PROG /REF & MAP/ Tekniques V3N6 Program Module Cross Reference & Map
9 ASCII PROG / " " /
10 ASCII PROG /GPIB GET / Tekniques V3N7 GPIB GET Command Trigger
11 ASCII PROG / " " /
12 ASCII PROG /FI SUBRTN/ Tekniques V3N6 File Identifier
13 ASCII PROG /SLIDEMAKE/ Tekniques V3N6 Slidemaker II
14 ASCII DATA / " " /
15 ASCII PROG / " " /
16 ASCII PROG /Q-PLOT / Tekniques V3N6 Q-Plot
17 ASCII PROG /SYMBOLGEN/
18 LASTPlus I will be posting the MC6800 to my repository - and likely adding it to my Flash Drive!
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