Do you know what type of connector this is?
Posted by asganawayaway@reddit | vintagecomputing | View on Reddit | 97 comments
I’ve found it in a stash. It is connected to a Teac IBM Floppy Drive 1.44MB p/n: 19308410-01. So far on the internet I’ve only found smaller ones. It’s very, very heavy.
Coupe368@reddit
This post makes me feel old.
wornoutnodes@reddit
Ah yeah, the good old days of massive connector cables....
... I feel your pain.
AboveAverage1988@reddit
You remember the noise the printers made you connected with these?
Coupe368@reddit
Fondly.
Bipogram@reddit
I am a pile of dust.
I feel nothing.
edna7987@reddit
Same my friend, it will only get more common
goldenbug@reddit
A couple of months ago I went into a Best Buy and the guys at the door didn’t know what a DVI connector was. Sigh.
randombits0110@reddit
WHAT??? SPEAK LOUDER, I CANT HEAR YOU….
reditanian@reddit
I am on this sub because I like computers and I am vintage 😅
Guestenye@reddit
Came here to stay this.
Human-Suspect-232@reddit
Dangggg , that thing is that old? At the first glance I thought SCSI.
Cowboy_0629@reddit
Serial port
Caltech-WireWizard@reddit
It’s simply a DB-25 connector. Those were used for MANY applications. The most common applications were:
- Parallel port for printers.
- Serial Port (RS-232) interface for MODEMS & communications
Mills2102@reddit
Parallel port
leongrozavu@reddit
USB C
FujiKitakyusho@reddit
The end in your hand is a DE-25 male.
r_a_d_@reddit
looks like a parallel port floppy disk drive? 1.44MB
AlatusU@reddit
A big one
asganawayaway@reddit (OP)
And heavy …
Realistic-Secret-590@reddit
SCSSI connector - yeah, I'm that old...
chandleya@reddit
It’s a DB25
BUUUUT
I highly doubt that it’s just any old parallel port. This is likely dependent on a Thinkpad firmware trick to stop using the parallel port for LPT/ECP comms and effectively rewrite it as just a floppy.
Which is cool. But not so reuseable. I bet someone out there really wants this. Straight to eBay
Cwc2413@reddit
This… also, I thought some early SCSC variations had a DB25 option. Iomega is the one I am thinking of but there could have been more.
Cwc2413@reddit
https://www.reddit.com/r/OldTech/s/rIxCyspn0k I just found this in another thread. The old Syquest drives had this type of connector as well.
Far_Relationship_742@reddit
Assuming you mean SCSI, Apple used a DB25 for SCSI on everything but PowerBooks.
miner_cooling_trials@reddit
I once had a parallel Zip drive. Until I got an internal one that fit in the 3.5 floppy space.
bhiga@reddit
Less common later but DB25 was also used for serial, and DE9-DB25 adapters were common. There were also "graphics printer" cables that were DB25 to DE9 but internally they swapped Tx/Rx so built-in null modem. Discovered this when trying to play DOOM with a friend and it didn't work until I removed the null-modem adapter that I thought I needed from the chain.
laf1157@reddit
25 pin RS 232
desmond_koh@reddit
Strictly speaking, the connector is a DB25. It was designed to connect to the parallel port (i.e. printer port, LPT1, LPT2, etc.) on your computer. Parallel ports allowed for faster data transfer than serial ports, up to about 4 Mbsp if I remember correctly.
Short_Juggernaut9799@reddit
The type D "subminiature" connectors were designed by Cannon in 1952. Decades later, in the early 80s, IBM used this connector to implement a parallel port on the original IBM PC.
asganawayaway@reddit (OP)
This one is made by IBM Corporation, so it’s probably from the late 80s/early 90s.
johnnycantreddit@reddit
Good wye! IBM : 1981. IEEE 1284. Based on Centronics standard for Parallel Printers. Just before, a bigger connector but the DB25 was a smaller bulkhead punch than the Amphenol 36 pin ribbon type connector which was a pain to punch/crimp. I still have these ancient tools downstairs. I built a lot of Apple clones back then for side hustle (my own was an SBC called the AIM65 which I still also have).
Does anybody recall Laplink DB25 to DB25 crossed cables. Still have. And a 5.25 with LL3.
kriebz@reddit
This looks like an adapter to connect a floppy drive that would normally be inside a laptop to the laptop externally when the bay was used for something else. This probably requires a laptop with the non-standard ability to detect the drive and alter the function of the parallel port to support it.
RFC793@reddit
In theory, you could implement a floppy disk interface over standard or enhanced parallel port without having to repurpose the port.
What I mean is, it didn't necessarily have to do a hardware mux from a parallel port controller to PC/ T floppy disk controller. But you could in theory have a scheme that runs over parallel port natively with a software driver on the host.
uberRegenbogen@reddit
Like Iomega did that with the parallel port version of the Zip Disk drive. (There was also an SCSI version—which, unfortunately, probably had the same DB25 plug. I don't know what would happen if you plugged one into the other.)
Datan0de@reddit
Could that be handled through software or a driver?
dst1980@reddit
Possibly, but probably not. It is a nonstandard use of the port and relies on the system to understand that it is in the alternate mode. Pinout may be documented, but it likely relies on some extra hardware trickery to work.
I suspect that internally there is some sense circuitry that recognizes the FDD and re-routes connection from the LPT chip to the FDD chip.
Multiple brands did this - Toshiba and Dell also did this, but the cables are not compatible with drives/systems from other brands. This suggests that pinouts are not compatible between brands. Some brands also had different cables for different models of laptop. This makes chances of a driver made very unlikely.
Datan0de@reddit
Thank you. That makes sense.
asganawayaway@reddit (OP)
I think this is correct. I was told this was the case and you’d bring this around to connect to the laptop in case you needed to. It’s an adapter for a much smaller plug. I posted some more pictures on my profile.
dpdxguy@reddit
DB-25 was the standard RS-232 (serial port) connector long before IBM used it for its parallel port connector on the PC.
Jimxor@reddit
Agreed. I used these DB-25 connectors a lot for RS-232 serial connections between computers before internet. It was more common to use them between terminals and data sets (modems). Usually only three of the 25 pins were used. Memory fades but I believe pin 1 was one of the grounds, pin 3 was what the modem used for transmission and pin 2 was the three "T"s: Terminal Transmits on Two.
It's ironic that DB-25 connectors were more "universal" back then than Universal Serial Bus connectors are today.
It was amazing how versatile those USART chips were. You could choose among 1, 2, or 1½ stop bits. Yes, 1½ bits. What does a half a bit even mean? (He asked rhetorically.) You could even configure them to use current differentials instead of voltage differentials to distinguish between 1s and 0s.
dpdxguy@reddit
There are several other signals (RTS, CTS, et. al) in a full serial port implementation. And the DB-25 RS-232 pinout specifies multiple serial communication channels.
You're correct that it was not uncommon for only TXD, RXD and ground to be connected. But many datacom protocols used those additional signals too.
Been a long time since I thought about any of this. :)
Great_Specialist_267@reddit
DB-25’s frequently carried multiple serial ports while maintaining compatibility with the basic RS-232 interface. Having a RS-485 or 20mA (TTY) current loop was common.
kyrsjo@reddit
Aah, so that's why they used such a gigantic plug!
SpikeHolden@reddit
I have been using one to connect my PC to my Ti99 to transfer files. Not the easiest thing to set up these days!
RFC793@reddit
Indeed, but for this particular case, assuming IBM/compat which is fair considering it is IBM: this is gendered for parallel port.
skrglywtts@reddit
PCs in the late 80s had Centronics ports for parallel comms.
dpdxguy@reddit
Some did. IBM was the first to use a DB-25 instead of the Centronics CN-36 connector specified by IEEE 1284.
desmond_koh@reddit
Yes, I know. I used to solder these connectors up to connect green-screen dumb terminals to our mainframe via serial ports.
elucify@reddit
There is also a DB25 pin out for rs232 serial. Never understood why
RFC793@reddit
It could carry more status lines than the db-9 variant. Fully supporting dummy terminals of the time, etc.
benryves@reddit
That's DE-9, rather than DB-9. The letter indicates the shell size - compare DE-15 (used for VGA ports) and DA-15 (used for joystick ports), for example.
yeehah@reddit
I always used to label the 9-pin serial connectors on my schematics DE-9, and the techs who were building the hardware would ask, "All we have is DB-9s. Will those be okay?" I'd explain the history of ITT Canon subminiature connectors, we'd have a laugh, and they probably called me a pedantic asshole once I left the room. But I was technically correct.
uberRegenbogen@reddit
I'm glad someone besides me said it, for once. 🙂
uberRegenbogen@reddit
The DE9 variant has the handshaking signals (except when some numbnut “engineer” left them out—leading to headaches at high speeds). I gather that the DB25 variant is for multiple channels.
MrWonderfulPoop@reddit
Old serial ports used DB25 as well. My old Wyse terminal has it.
ILikeBumblebees@reddit
DB25 connectors were used for parallel ports, but weren't designed for them. D-Sub connectors predate the IBM-PC architecture by decades, and have been used for a wide variety of interfaces. In the PC world, they're used for both parallel ports and RS232 serial ports, which are completely different things.
desmond_koh@reddit
Yes, you are absolutely right. And that wasn't what I meant to say (although it is objectively what I said). The "it" in my second sentence was meant to refer to the device in OP's post.
nyckidryan@reddit
25 pin parallel port (aka printer/LPT1) cable.
kevsterd@reddit
Missed most of this. Its a floppy designed to connect to an old parallel port. No doubt it probably still works, even though FDD support has been removed from later versions of Windows.
Yes, they shared the size DB25 with serial/RS232 but they key fact on PC's of the era that a 25 way female was Paralell or Centronics as it was known.
Serial ports on PC end were always male, regardless of if they were DB25 or later DB9. If you recall it's down to wether they are a DTE or DCE.
Happy to wake some brain cells...
No_Group5174@reddit
God I'm old.
vacantsouls@reddit
Apparently I am too.
4x4Welder@reddit
I'm still coming to terms with it having been around 20 years since I've seen this connector in the wild, and was already an adult then. Getting old sucks, but occasionally being slapped across the face with decades is the shock they don't warn you about.
No-Succotash-9576@reddit
Parallel port
LagrangianMechanic@reddit
DB25 was used for a bunch more things than just that.
DiligentEnthusiasm76@reddit
DB25 only has 25 pins. That connector is definitely of a DB class but the actual number of pins is needed for a good ID
DiligentEnthusiasm76@reddit
I think it has too many pins
Baselet@reddit
That's not a connector type.
MatthiasWM@reddit
It was also used for SCSI connections.
DiligentEnthusiasm76@reddit
That looks like an old SCSI cable connector but I can't count the number of pins from the picture. Check Wikipedia on SCSI as they should have pictures of the different connectors used for the different protocols used. Hope that helps.
EngineerMinded@reddit
DB25 paralell port. Used to be used for printers and RS-485 interfaces among other things.
Killertigger@reddit
DB25 - originally intended as the parallel port standard for printers; later the pin-out was re-wired from the standard fur use as proprietary data bus connectors for such things as external floppy drives (primarily IBM) and hybrid storage drives such as Iomega Zip and Jazz drives. Zip and Jazz drives were basically ejectable super-sized floppy drive cartridges in an external drive that acted like portable hard drives. I believe there were also external tape backup drives that use this connector, but I could be wrong. This may be worth something on eBay.
ILikeBumblebees@reddit
DB-25 connectors predate PC parallel ports by decades.
waterwingz@reddit
Yup - and some of us can still tell you which of those pins were used for what on its original usage for an RS232C serial port between a terminal and a modem.
Sergio_Poduno@reddit
DB25 male.
momentimori@reddit
When printers used this connector they were included with them. Once they moved to usb in the late 90s they stopped including cables.
ViG701@reddit
If you want to start and argument, ask an electrician if it's a male or female end. ;)
Bipogram@reddit
?:)
This is clearly female.
ViG701@reddit
Electricians go by the hood not the pins. No idea why.
Bipogram@reddit
TIL.
Am not electrician, clearly!
kanakamaoli@reddit
Count the pins. 25 in a d shell. Its a 25 pin connector. Could be a parallel port printer, could be a 25 pin serial port, could be a custom pinout. You won't know until you find the manual for the device and see what it needs to plug into.
Dannynerd41@reddit
duh
Dannynerd41@reddit
floppy connector
mtutty@reddit
Yes.
asganawayaway@reddit (OP)
I know that too now eheh
ThersATypo@reddit
That is very very nice to have!
capsteve@reddit
DB25 is the connector type, it was used for a variety of things, including scsi.
Often the host would have DB25 female port, and you’d plug in a cable that has DB25 male one one end and centronics on the other end, and each device had a number clicker to set scci-id between 1-7.
The item in pix looks like an ibm thinkbook cdrom drive, so it could be either ATA or scsi
paulrich_nb@reddit
Yes I do.
asganawayaway@reddit (OP)
🥸
ProfessionalGain2306@reddit
IBM PC
creativetag@reddit
DB25. Used generically for many things. The parallel port for printing, serial communications (though many defined signals unused and simplified to DB9), scsi-1 simplified external disk interface (often found on apple and some pc products, though DB50 was the standard), PIO adaptors, external peripherals like zip drives, etc, etc.
paulgraz@reddit
If I'm not mistaken, you can remove that adapter when connecting to the ibm Thinkpad docking station
pho3nix_@reddit
Born after 2005 probably. os a LPT port for printers and scanners in 90 and 2000.
CompuDocUt@reddit
It is a D sub connector you count the number
Of pins and that will give you the number it has bevel ed edges so it can only plug in one way they made D 9,15,25…..50 and possibly larger connectors they are used on may different kinds of equipment the most common for computers 9 15 and 25 9 was used for serial and CGA the 15 for VGA the 25 for serial
RolandMT32@reddit
Yes, I know what kind of connector that is.
asganawayaway@reddit (OP)
🥸
PositionDistinct5315@reddit
Count number of pins, add prefix "DB-", done.
JoopIdema@reddit
It is called a Db25