Epson TM T20II printer prints by itself and symbols

Hello,

this printer is a ticket or receipt printer, which is very common among retailers...

Often, it is connected to the PC via a serial RS232 connection... Unfortunately, I have browsed the Epson website and this printer model must have a longer reference... for example, Epson TM-T20II (002CS), otherwise it may not be a serial connection..??

The problem you mentioned here is typical of poor configuration between the printer and the PC (data bit length, start/stop bit, parity bit or not)
Study the issue here http://www.avsaudiovisuel.fr/datafiles/public_data/Articles_general/telechargement/liaison_serie_rs232.pdf

-- You need to know in what format the data frame from the PC comes out... depending on the application
-- Next, you need to study the printer's manual to understand how to configure it
-- And you configure the printer to match the same format as the PC output

-- Many PCs have an existing serial connection on the motherboard, so there is no need to use a PCIe card... you just need to use the pins provided on the motherboard.

In the printer, this may involve microswitches or memory or a menu or a way to operate.

Hello,

So it's a ticket printer

I am connected via parallel port
The model is Epson TM-T200II (002)

For me, the settings are correct whether from the PC or the printer; maybe I didn't look carefully enough, I'll check once more.

Since last night, it hasn’t printed on its own and there's no symbol visible, but it doesn't print any test page

No, in fact, there is no serial connection on the motherboard; otherwise, I wouldn't have had to add one.

I'm sorry, this model does not have a parallel port... only serial and USB... so either there is an error, or the connection cannot work like this.

The parallel port is either a Centronics connector or a DB 25-pin, whereas the serial connection is a DB9; they cannot be confused... but I can't see from a distance. A photo of the ports maybe..??

On a parallel port, you can't make a mistake if the cable is well made... However, on a serial port, you could search for the right configuration all day long.
There’s still the type of cable used..??

You can try testing with the HyperTerminal on the PC and/or the xmodem protocol
https://courselectronique.fr/rs232/

I would have preferred to have the brand and model of the motherboard..??

So here is the card that I added to my PC, it has serial ports and the DB25 (what does DB mean?) just like on my printer. I had connected it like the client I have with DB25 to my PCIe card and to my printer. It turned out that no matter what I did, it did not print, but maybe because the DB port was not properly configured.. can you tell me more about the DB25 pins?

Because when I connect in DB9 serial and DB25 input on my printer, there is no issue printing

As for the motherboard, it's a Dell, but for the model, it's an Optiplex 3080 PC; I haven't found the model of the motherboard

EDIT:

I just realized DB25 is also a serial port?

So actually when I connect my printer only in DB25, there is no printing
But I connect in PC output in DB9 and in printer input in DB25, no issue printing

So it’s the configuration of the DB25 port that is not working or did I configure it incorrectly?

Another https://www.eltima.com/fr/article/9-pin-serial-port.html

DB stands for "Data Bus" since it is a data transmission.

I was expecting a photo of the back of the printer where the connector is located...

-- I see that your card output is a kind of octopus with three types out.
And I found this card https://www.startech.com/en-us/cards-adapters/pex2s1p553b

This card output with three cables is actually:
-- 1 parallel port...25 pins
-- 2 serial ports...9 pins
So which one is connected to your printer
And the two serial ports are certainly on two different COM addresses: COM1: and COM2:-- or 3..4..5..etc..? And there is a CD included to set all this up

The driver file https://sgcdn.startech.com/005329/media/sets/asix_moschip-mcs99xx_drivers/[asix%20moschip%2099xx]%20pcie%20serial%20card.zip

-- You need to be sure to use the right cable, and that it is properly indicated in the config, the correct COM address

-- The number of data bits (often 7 or 8)
-- The parity bit or not
-- The stop bit or not
-- The start bit or not

It would be interesting to know if this installation has ever worked..?? or never..?? with this same PC and the same version of Windows..??

It would also be interesting to see the text from the configuration paper, printed out from the printer..?

I also think that the software for the ticket/receipt must have a printed data format, which is known, either for sale, or in the specifications...

The goal being to marry the two.

Re,

As I mentioned, behind the printer it's a DB25 female, otherwise there is USB or Ethernet but that’s not what I'm interested in.

Yes, it is indeed a StarTech PCIe 2S1P, the drivers are correct.

I tested on two different PCs and when I connect DB25 on both sides nothing prints.

When I connect DB9 on the PC and DB25 on the printer, it works fine.

So I don’t know where the issue comes from, but with DB25 on both sides, it's impossible to print.

I have the correct configuration:
data bit: 8
Parity: none
stop bit: 1
start bit: none

When I output the printer's configuration:



For the text configuration, I verified on the internet, it is correct.

At work, I only have a double DB25 cable, so it might be that, but I cannot check with another cable.

For me, it's the fact that I connect with double DB25 that causes everything to fail, because I don’t understand why it works fine when I connect in series, but when I use the parallel port, it doesn’t work.

The female DB25 connector at the end of the octopus is a parallel port and not a serial port... it is designed to receive a male DB25 cable ===> printer... I haven't seen its connector..

-- On the configuration ticket, it is the (serial or USB) connection that is selected... so you cannot print in parallel... But only in serial, so in your case.. DB9 at 38400 baud..

I don't quite understand that..

When I connect DB9 to the PC and DB25 to the printer, it works correctly

Send a photo of the back of this printer... how many connectors are there..?? and what are the contacts like.....?

As I told you, the printer has a DB25 female connection, I believe. Here is the image



Yes, indeed, but when I want to choose to change the interface, I am offered UIB, Built-in USB, or Auto, which is the default value

And as I told you, the DB9 printer works without any issue, but when I connect the DB25 parallel port "at the end of the octopus" and on my printer it's also DB25, it doesn't work.

I find this whole affair quite curious...!!! It is indeed a female DB25 coming out of the printer and the octopus... Normally, they should be connected with a male DB25 cable at both ends and the printer should be set to parallel mode...

-- I suppose that if it doesn't work, it’s because a connection is broken somewhere, or short-circuited with the neighboring terminal... or that the wiring is not correct, crossed wires or missing etc..

-- However, I don't understand how you can connect the DB9 to this printer which doesn't have a DB9 connector..??
Or do you have a female DB9 on one end and a male DB25 on the other... that’s possible... but in that case, it means that your DB25 from the printer is actually a serial connection and not parallel.

There lies the puzzle..?

Hello,

So yeah, when I use a DB25 cable on both ends, it doesn't work because I can't set the printer to parallel mode since it doesn't exist.

And yes, I also have a DB9 female and DB25 male cable on the other side, and the printer works fine with the correct settings, especially the port speed of 38400; otherwise, it only prints symbols.

OK, so for me, this printer is equipped with a DB25 for a serial connection (RS232)... by the way, the setup seems to be a "cobbled together" adaptation..? in any case, for it to work this way, the connection and the protocol must be well respected and the intermediate cable is certainly adapted as well for it to function this way

-- The transmission speed is 38400 baud. If this speed is modified, the transmitted bits are no longer synchronized and the decoding of the printed characters is no longer the same, which is why it prints random stuff.

-- On a "normal" machine, we should be able to change this speed, up to 115200.. But it needs to be done on the PC side as well as on the printer for everything to be in agreement... It’s not certain that we can change these values on the printer..?? it might be unnecessary if the speed of its mechanics can't be faster.. It takes time for thermal printing..

Indeed, in a manual https://www.modesdemploi.fr/epson/tm-t20ii/mode-d-emploi?p=2
there is indeed a DB-9 <==> DB25 cable which is for the RS232 connection model
So this DB25 connector is indeed a serial connection... it's a trap

Yes, indeed we can see it on the photo of the back of this printer, it's not very legible but it says "RS-232", so it’s not a parallel connection.

In any case, thank you for helping me sort out this printer, now I just have to call the client to share my findings ^^

Thanks again jeannets

OK here is the document you asked for A+++