开云体育

Still chasing a working copy or original of the Diagnostics Tape for the
4041.
DaveB, NZ

Dave,

I just got one of my Tektronix 4041 computers working this morning.

I have a System Verification tape - that boots, but has a program error trying to load the terminal console program.

I've got my 4041 connected to my laptop with the COM0 RS-232. I'll see if I can get the System tape copied.

Monty

Photos of my 4041 on my thread on
vcfed.org: !!&p=622704#post622704

Hi Monty,
There might be a few causes for this. The tape heads should be cleaned since that's the easiest thing to try. I am not familiar if demagnetizing them is also appropriate on occasion. The tape drive was probably bought from a manufacturer. If you can find the model number you may be able to locate a service manual for it that has information about routine cleaning and servicing.

The rubber capstan wheels are probably dried out causing the tape speed to wander. I think there are coatings that can be applied that make them more supple but it has been a while since I did anything like this.

Your tape may have bit rot. Nothing is permanent and bits can change when the magnetic media changes. This would vary due to how the tape was stored. You may be able to buy a replacement tape from the vintageTEK Museum.

I think there may be more members with 4041s on TekScopes. One of them might have a tape you can use.

Good luck, It sounds like you're having fun. When you get it working post some pictures in our photos section.

Dennis Tillman W7pF

[email protected], hp9845.net and other places have lots of info about these drives and tapes. The tapes tend to physically lose their coating and the polyurethane drive capstans crumble or become chewing gum. I think you're lucky that things work at all!
Repairs and mods for these drives are described in said places. You've probably got the plastibands suggestion from one of them.

Raymond

Please let me know if you ever manage to copy the tape for the 4041. My
tape has become flaky over the past 40 years. I would be willing to pay for
a working copy of the tape.

Gary Bosworth

--
Gary Robert Bosworth
grbosworth@...
Tel: 310-317-2247

Ditto- my 4041 has been languishing in the corner for some years now.
DaveB, NZ

Nothing technical to contribute here, but mention of the 4041 reminded me of something. In building 63 I saw a poster of an exhausted distance runner breaking the finish line tape. Someone had captioned it “4041 PSR”. (Stands for Product Shipment Release.) I guess the design cycle encountered some trouble.

Dave Wise
Information Display Division 1980-1995

I made progress today and believe I have recovered all the files on my 4041 System Verification tape v 2.8.

Here is the 'long' directory for that tape:

<div>
SYSVER 2.8 29-APR-85 09:46:04 SOFT ERRORS = 0
FILE FILE LENGTH START NUMBER LAST
NAME TYPE IN BYTES RECORD OF REC. MODIFICATION DATE
------ ---- -------- ------ ------- ------------------
AUTOLD IT 2550 5 10 13-SEP-84 16:08:00
TERMIN IT 8160 15 32 13-SEP-84 16:08:00
SYSVER IT 3570 47 14 13-SEP-84 16:09:00
CONFIG AS 510 61 2 01-JAN-81 00:02:00
255
PROCED IT 1020 64 4 13-SEP-84 16:09:00
LINK IT 765 68 3 13-SEP-84 16:09:00
DISP IT 1275 71 5 13-SEP-84 16:09:00
KEYPAD IT 1530 76 6 13-SEP-84 16:09:00
PRINTE IT 765 82 3 13-SEP-84 16:09:00
TAPE IT 4590 85 18 13-SEP-84 16:10:00
SOFTER IT 765 103 3 13-SEP-84 16:10:00
IO IT 4590 106 18 13-SEP-84 16:10:00
255
TIMER IT 1530 125 6 13-SEP-84 16:10:00
PDKYBD IT 4335 131 17 13-SEP-84 16:11:00
GPIB IT 2040 148 8 13-SEP-84 16:11:00
GPIBLB IT 3315 156 13 13-SEP-84 16:11:00
GPIBCO IT 2040 169 8 13-SEP-84 16:11:00
SLAVE IT 3315 177 13 13-SEP-84 16:11:00
MASTER IT 1785 190 7 13-SEP-84 16:12:00
PAUS IT 765 197 3 13-SEP-84 16:12:00
TPCAL IT 1275 200 5 13-SEP-84 16:12:00
PTRCAL IT 1020 205 4 13-SEP-84 16:12:00
FRMAT IT 1020 209 4 13-SEP-84 16:12:00
TSTPTN IT 2040 213 8 13-SEP-84 16:12:00
CHKOPT IT 1275 221 5 18-SEP-84 13:04:00
OPT2 IT 765 226 3 13-SEP-84 16:12:00
HELP IT 3060 229 12 13-SEP-84 16:12:00
PDTEST IT 255 241 1 13-SEP-84 16:12:00
SCSI IT 2550 242 10 13-SEP-84 16:13:00
TSYSVR AS 4080 252 16 13-SEP-84 16:13:00
TSCSI AS 3315 268 13 13-SEP-84 16:13:00
TDIR AS 2295 281 9 01-JAN-81 00:25:00
94605
</div>

I posted the files I recovered on my new 4041 github repository:


I also posted the ASCII text version of all the programs.

I had issues with using the 4 1/4 inch Plastibands as DC100 tape drive belt replacements but got the verification tape files recovered.

I'm still having issues trying to use the LEMO keyboard connector to get into serial mode.

I recovered the .IT files with: COPY "filename" TO "COMM0:".
I got the ASCII versions of those files with: LOAD "filename", then LIST

I edited the * prompt character out of all the .IT and .ASC files

I'll wait for some smaller Plastibands that I ordered today to arrive before attempting to format one of my tapes and see if I can create a System Verification copy tape.

I see my attempt at formatting the directory listing didn't work :(

I captured ROM images from the CPU and all the Option ROMs back in 2000 when I bought my 4041, I'll be uploading those ROM images to my github repository later today.

4041 Program Development ROMs 1 and 2
4041 Graphics ROM
4041 Plotting ROM
4041 Signal Processing ROM
4041 Utility ROM #1

The Utility ROM has an interesting feature "PROM File System" and says the user can build a PROM from files on a tape. If the PROM contains an AUTOLD file, PROM0 will become the SYSDEV device to boot the system.


Here is a doc I wrote in 2000 about capturing the ROMs and what ROM carriers Tektronix used. Looks like I ordered some sockets and carriers - but I don't know where they are after all this time :(
--------------------------------------------------

TEKTRONIX 4041 OPTION ROMS – Oct 2, 2000 mcm

I got two Tek 4041 GPIB controllers. Both had the programming ROM set. One had four other option ROM sets: 4041R01 Graphics, 4041R02 Plotting, 4041R03 Signal Processing, and 4041R04 Utility – all labeled Version 2.1

The Option ROMs were in 24pin Molex Low-insertion force carriers P/N 8878 24-D, the ROM tray used Molex 8878 24S sockets. Neither of these parts could be found on an internet search. I went to the Molex website and found they still make 24 pin LIF carriers 50-39-5248 and matching sockets but I couldn’t find any in stock in internet electronics distributors. The 28 pin versions were in stock and around $2.50 a mated set at Carlton-Bates, so I ordered 6 sockets 15-29-9282 and 16 carriers 50-39-5288.

I used a Dremel to modify one 28 pin socket (pulled out two contacts at pins 13 and 16 and then Dremeled a groove on each side to accept the Tek 24 pin carriers. The carriers have one notch on the pin 1 end and two notches on the pin 12 end.

The Graphics ROMs were Motorola 68766C35 24pin 8Kx8 EPROMs.

Using my Data I/O Model 29B /w Unipak2 – Family 25/Pinout 29, I read each EPROM and transferred the data to the PC. Set Translation Format to 83 so they can be loaded into PC with DEBUG.COM HEX files can be loaded with DEBUG. TXT files are in the default Data I/O format 81.

‘Left ROM’ Checksum ‘Right ROM’ Checksum
Part Number Part Number
Graphics ROMs B020801 160-1755-01 96F5 160-1756-01 2071
Plotting ROMs B010807 160-1889-00 4D5F 160-1890-00 1938
Signal Procesn B010818 160-1984-00 4057 160-1985-00 945E
Utility #1 ROM B020781 160-2221-01 1034 160-2222-01 721B

The pgm dev ROMs were also 67866C35 EPROMs:

Pgm Dev ROM1 4041F30 160-1246-03 C533 160-1247-03 C915
Pgm Dev ROM2 4041F30 160-1335-03 7760 160-1336-03 EB34

The other 4041 had Pgm Dev ROMs version 2.0

Pgm Dev ROM1 4041F30 160-1246-02 C34E 160-1247-02 C250
Pgm Dev ROM2 4041F30 160-1335-02 5D6B 160-1336-02 C8DE

Good news/info thanks, Monty
I'll dig my 4041 out and check what's there again-think I have some of those ROMS as well.
DaveB, NZ

Dennis,

I added a Tektronix 4041 photo album with photos of my 4041 running the System Verification tape.

/g/TekScopes/photo/247590/5?p=Created,,,20,2,0,0

Monty

Thanks for posting all this valuable information.

For your problems with the LEMO keyboard connector check the signal levels on the data input.

The keyboard input uses TTL logic levels but there is a very heavy internal pull-up resistor on the 4041 keyboard serial data input. You will need to sink about 20mA to get an adequate logic low level and, although this was OK when driven with the older bipolar TTL devices, most modern CMOS-based interface chips would struggle to sink this much current.

Thank you for this information.

I was trying to use a Parallax USB to serial converter, I think the ASIC direct drives the pins. I'll look at trying to add a buffer IC for more drive on the TX pin. Or maybe find the pullup resistor and put in a bigger one :)

Monty

I found two resistors next to the keyboard header on the CPU board. One was about 130 ohms to Ground, the other was about 120 ohms to +5V.
The other end of both resistors next to the keyboard header was connected on the PCB to the TX pin from the keyboard.

I unsoldered the end of the 130 ohm and 120 ohm resistors on the opposite side from the keyboard header.

I inserted a 1K ohm resistor into the hole where the 120 ohm resistor was connected to +5V and connected the other end of that resistor to the end of the 120 ohm resistor.

I didn't have to remove the CPU board for this operation.

This allowed my Parallax USB to TTL serial to work. This converter has female pins and I used Arduino breadboard jumpers to connect the serial interface to the LEMO pins.

From the front panel, the top left LEMO female socket is Ground - and was connected to the Parallax Vss pin.
The bottom left male pin on the LEMO is the TX pin from the keyboard and I connected it to the Parallax TX pin.

I could now type on the PC Realterm application (4800 8N2) and see the output on the red LEDs on the front panel.

I then typed two commands - from maddisassembler in 2016 "RE: 4041 basic program for redirection", but left off the line numbers and typed in immediate mode:

SET DRIVER "COMM0(BAU=9600,FLA=BID):"
SET CONSOLE "COMM0:"

I got an error message on the second command. The operators manual shows "SET CONSOLE "COMM:", so I typed that and that text stayed on the LED display - but my serial console was then enabled.

I guess COMM0 is needed if you have the second COMM port option. The 4041 I was using has only one COMM port.

I uploaded a photo of my simple mod. I left the two original resistors if I wanted to restore to original later.

/g/TekScopes/photo/247590/0?p=Created,,,20,2,0,0

Monty

Monty,

Good to see you have now established communication with the keyboard port. You are correct that the COMM0 port description is required for a 4041 with the dual RS232 port option.

I use the same technique since my tape drive doesn't work and I have to manually enter those commands every time the 4041 is powered up to redirect the console. I been thinking of automating the process by building a small microcontroller board that emulates the keyboard and outputs the necessary commands every time the 4041 is powered on. I haven't progressed this yet as I need to do some experiments to figure out when the 4041 has completed its power-up sequence and is ready to accept keyboard commands and how fast it can process those commands.

Stephen

Stephen,

I think it would be pretty simple to put an Arduino board inside the 4041 case - connected to the internal keyboard header, plus my resistor mod so the Arduino could direct drive serial into the 4041.

It might be easier to not worry about how long the 4041 takes to boot and just install an Arduino reset button on the back of the 4041. Press the Arduino reset button and the Arduino program would output the SET DRIVER and SET CONSOLE commands - which would require that the 4041 had the Program Development ROMs.

Does everyone on this thread already have those ROMs in their ROM Carrier?

Otherwise - the 4041 will only auto load an AUTOLD.IT program from tape - as the Program Development ROMs are required to run ASCII BASIC commands like SET DRIVER and SET CONSOLE.

Or someone needs to disassemble the Utility ROM and figure out how to make a PROM that would hold the AUTOLD.IT program to do the serial commands.

When I look at the 16-bit binary image of the Utility ROM, it looks organized similar to the Tektronix 4050 ROM packs, with a header, followed by ROM call names, each followed by the entry point address for that ROM call.

In addition the last 1024 bytes of the Utility ROM look like a template for the PROM image:

Offset(h) 00 01 02 03 04 05 06 07 08 09 0A 0B 0C 0D 0E 0F

00003C00 30 2B 00 20 47 F3 00 20 2B 4B 00 24 60 AA 4E 75 0+. Gó. +K.$`?Nu
00003C10 00 00 00 00 00 06 00 10 46 4F 52 84 00 08 41 53 ........FOR?..AS
00003C20 43 FF 00 00 49 54 45 FF 01 00 45 4F 4D 01 01 11 C?..ITE?..EOM...
00003C30 45 4F 55 01 01 10 45 4F 41 01 01 0F 45 4F 48 01 EOU...EOA...EOH.
00003C40 01 0E 00 00 00 00 46 69 6C 65 20 20 54 79 70 65 ......File Type
00003C50 20 20 53 69 7A 65 20 20 20 20 43 72 65 61 74 69 Size Creati
00003C60 6F 6E 20 44 61 74 65 20 20 5F 5F 5F 5F 20 20 5F on Date ____ _
00003C70 5F 5F 5F 20 20 5F 5F 5F 5F 20 5F 5F 5F 5F 5F 5F ___ ____ ______
00003C80 5F 5F 5F 5F 5F 5F 5F 5F 5F 5F 5F 5F 00 00 00 00 ____________....
00003C90 00 05 50 52 4F 4D 3A 00 00 00 00 00 00 00 00 00 ..PROM:.........
00003CA0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003CB0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003CC0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003CD0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003CE0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003CF0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D30 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D50 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D60 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D80 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003D90 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003DA0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003DB0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003DC0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003DD0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003DE0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003DF0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E30 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E50 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E60 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E80 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003E90 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003EA0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003EB0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003EC0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003ED0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003EE0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003EF0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F10 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F20 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F30 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F40 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F50 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F60 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F70 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F80 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003F90 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003FA0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003FB0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003FC0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003FD0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003FE0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00003FF0 FF FF FF FF 22 22 21 22 01 01 FE FE 3D 0F F4 20 ????""!"..??=.?

We can get the 4041 service manual scanned from the vintagetek.org microfiche library of all Tektronix documentation - after COVID-19 is over. Right now Oregon is still in lockdown. They only charge $25 an hour for scans.

I just finished creating the binary files for each of the Option ROMs v2.1 and also a 16bit binary that could be used for disassembly and posted them in the ROMs folder on my github repository for the 4041:

We would like to see working cassette tapes with 4041 functional programs
that can boot-up and test the 4041.
.

--
Gary Robert Bosworth
grbosworth@...
Tel: 310-317-2247

Gary,

I have ordered 15 NOS 3M DC100A tapes from EBAY. They are scheduled to arrive Sunday.

I hope the drive bands are still ok - but I may have to replace them with Plastibands.

I will try to format and create a System Verification tape from the files I have recovered and report the results here.

Does your 4041 have the Option 30 Programming Development Option ROMs?

Monty