I have been looking for a way to drive an Epson m185 printer mechanism, but I only found one video about driving the Epson m190 with an Arduino which did not provide any connection diagram between the mechanism and the Arduino. I am looking for any advice on how to drive the Epson m185 printer mechanism with an Arduino Nano (Atmega328p). I did take a look at the datasheet to figure out the timing, but I have no idea how to split a string into 5 sets of dots.
Providing a link to the datasheet would help us a lot. It's not exactly the everyday thing for most helpers.
Here is the datasheet
Thanks for trying. Scrolling through the document I'll say its a service manual, not a designers, OEM, manual.
Do You have any interface, driver, to it?
I do not have any driver for it, that is why I am asking for advice on how to drive such a printer mechanism (it has direct connections to the motor, solenoid, reed switch, tachogenerator and printhead).
On second thought I think I have a slightly different model, because mine has 5 hammers (the printhead originally held 6, but one was omitted during manufacture) and it prints onto 48mm wide sheets.
Turns out I might have the M180 instead (they are all similar)
Okey.
Knowing what voltage the motor needs is one question. Another question is the current needed for the needles.
If You want a printer, buy one having documenetation, maybe even an interface to micro controllers.
Bringing an old device to work costs a lot of work. Personally I'm not prepared for that.
The voltage for the motor and needles is said to be 5V (Epson themselves wrote that 5V is to be used). The resistance of the needle solenoids is supposed to be around 1.5 ohms.
And I didn't buy the printer mechanism as it was a part of a cash register printer (printer + keypad) that I got from my grandma
I got old clocks that were taken apart.
That will be 3.33 Amp per needle. Take that x times the number of needles plus motor current when You go for the power supply.
That current will need to be a very short pulse with relative high voltage to get the pin to fire and bounce back. How are the needles held in the solenoid? Are there small magnets?
There are springs to get the dot hammers back into their "parked" position, and that also pushes the solenoids into their origins.
You're supposed to put pulsed current through the solenoids in order to not fry them with the 16-ish watts of dissipation. And one more thing, don't use 12V for the needles. I had to make 2 new solenoid coils because I drove them with 12V.
I actually have the m185 printer.
Do you have the ribbon drive mechanism? Do you have the sensor for the carriage being in the home position?
I have the printer mechanism (the printhead, and both of the sensors (a reed switch telling the Arduino when the next line begins and a tachogenerator telling it the speed of the carriage (the voltage and frequency are proportional tp the speed of the motor.) ) )
And there is a spring that hopes to push the carriage (printhead) all the way to the left.
I had a one direction printer many years ago, just to see how it worked. Not Epson. But, do you see a connection between the print head and something to move the ribbon in the ribbon cartridge?