Driving an original OKI Microline 80 printer

[Andrew Mawson]

An original OKI Microline 80 has fallen into my hands, and apart from a faulty mains switch (fixed) seems to be in working order.

This is a 7 pin impact printer with a Centronics Parallel input port. Does anyone remember if they were character by character printers or line by line? I'd like to prove it working and was going to wire up a simple 7 bit wide switch bank (with strobe) so I can toggle ascii characters into it one by one but before I do, it would be nice to know what it expects.

Needless to say no Windows 7 drivers out there that I can find and I don't have a unix machine to hook it up to.

(I wish Microsoft had never dreamt up hardware abstraction layers ! Time was when I could send characters directly to a port address from a diddy program ! )

Andrew

[John Rumm]

It will normally print a line at a time - not all DM printers could stop and restart the head on one line. However if you sent it CR+LF (or possibly just a CR depending on how the dip switches are set) it will end the line and flush anything in its buffer on to the paper.

Not got a a parallel port on your machine?

Open a command prompt and copy / echo etc something to LPT1: and that will give you raw bytes to the port with little in the way of drivers in the way.

e.g.

echo Hello World >LPT1:

or

copy my-file.txt lpt1:

If you really want to bash the bits yourself you will need a device driver that permits low level IO from a user mode application like:

The go poing at IO locations 0x0378 for the data register[1] of LPT1: and 0x37A for the control reg (bit 0 is strobe)

[1] default address of first port for most systems unless they have a port on a MDA/Hercules card, in which case that is normally assigned to LPT1: at based address 0x3BC

[Andy Burns]

If you don't want to byte-bang it, there are/were USB->centronics dongles available, if they're no longer available I probably have a few stashed away.

The "Generic/Text Only" driver still seems to exist in Win10

[The Natural Philosopher]

Ive got somewhere a box with two parallel ports and an ethernet connection.

There are IIRC IIRC USB to parallel converters as well.

You can pick up a parallel serial IO card for peanuts as we well if needs be. The centronics cable will cost more!

[Mike Tomlinson]

En el artículo , Andrew Mawson escribió:

Character by character

why not just use a PC parallel port?

Win7 here offers "Oki Microline Generic 9 pin Dot Matrix Printer". That'll work.

You'll probably find the Epson FX-80 or RX=80 driver will also work.

You still can. LPT1 is on port 0x378 and has been for 36 years.

[Brian Gaff]

You should have kept hold of an old Sinclair Spectrum plus 3. they have a port and just need a cable with the ole amstrad edge connector on one end and the printer plug on the other.

I'm sure many old machines from that era could drive it. Probably used the old Epson control codes etc.

Brian

[mick]

wow..... I've still got one of those, c/w the roll stand to take teletype rolls. No idea if it still works. I think I last used it with a Tandy model 1.

It's a 7-bit printer. Only characters - no dot graphics mode. No descenders on lower case characters. The normal interface is a normal Centronics parallel, although they were available with a RS-232 serial port at one time. IIRC you send a string of characters terminated by CRLF. The line is then printed. It''s many years since I ran it though - I could be wrong. Control codes are just the standard Epson ones.

Ideally you want a PC parallel port to drive it. You can, however, get Serial to Centronics, USB to Centronics and Ethernet print servers for Centronics.

[Andrew Mawson]

Thanks John, it's frightening how you (I) forget these things - yes that's proved that it's working :)

Andrew

[Andrew Mawson]

Welcome to the OKI Microline 80 club !

Yes I've managed to output to it via a command prompt so at least I now know that it's working :)

Andrew