Print a postscript document with CUPS and a thermal printer
I installed an epson TM-T20 in Ubuntu 12.04, using the official driver. This is a thermal printer, I'm using 80mm paper.
My problem: When I print an image (using a postscript document) it waste a lot of paper because the image uses around 5cm and the printer before the image sends out 25cm of white paper.
I use the following command to send the document to the printer:
lpr -P tm-t20 -o document.ps
The printer prints the image (a 200x200 image), but first sends out a lot of non printed paper.
The printer wasn't recognized by CUPS (using the web interface at localhost:631). Then I installed it using the following procedure:
sudo lpadmin -p tm-t20 -E -v serial:/dev/ttyUSB0 -P /usr/share/ppd/epson-tm-t20-rastertotmt.ppd
Then the printer appeared in the CUPS web interface and I configured it (baud rate, bit parity, etc).
The printer works ok when I send some text.
Here is part of the printer ppd:
*DefaultPageRegion:RP80x297
*PageRegion RP80x297/Roll Paper 80 x 297 mm: "<</PageSize[204 841.8]/ ImagingBBox null>>setpagedevice"
*PageRegion RP58x297/Roll Paper 58 x 297 mm: "<</PageSize[141.7 841.8]/ ImagingBBox null>>setpagedevice"
*CloseUI: *PageRegion
*DefaultImageableArea: RP80x297
*ImageableArea RP80x297/Roll Paper 80 x 297 mm: "0 0 204 841.8"
*ImageableArea RP58x297/Roll Paper 58 x 297 mm: "0 0 141.7 841.8"
*DefaultPaperDimension: RP80x297
*PaperDimension RP80x297/Roll Paper 80 x 297 mm: "204 841.8"
*PaperDimension RP58x297/Roll Paper 58 x 297 mm: "141.7 841.8"
I suppose that this waste of paper is because the 297mm of long that appears in the ppd file. Then I tried adding another configuration of 100mm instead of 297mm, but the problem persists.
I also tryied adding the tag %%DocumentMedia to the ps file, but the same problem:
%!PS-Adobe-3.0
%%Creator: GIMP PostScript file plugin V 1.17 by Peter Kirchgessner
%%Title: yay.ps
%%CreationDate: Thu Sep 13 13:44:26 2012
%%DocumentData: Clean7Bit
%%LanguageLevel: 2
%%Pages: 1
%%BoundingBox: 14 14 215 215
%%
%%EndComments
%%DocumentMedia: Plain 72 72 0 white Plain
%%BeginProlog
% Use own dictionary to avoid conflicts
10 dict begin
%%EndProlog
%%Page: 1 1
% Translate for offset
14.173228346456694 14.173228346456694 translate
% Translate to begin of first scanline
0 199.99999999999997 translate
199.99999999999997 -199.99999999999997 scale
% Image geometry
200 200 8
% Transformation matrix
[ 200 0 0 200 0 0 ]
% Strings to hold RGB-samples per scanline
/rstr 200 string def
/gstr 200 string def
/bstr 200 string def
{currentfile /ASCII85Decode filter /RunLengthDecode filter rstr readstring pop}
{currentfile /ASCII85Decode filter /RunLengthDecode filter gstr readstring pop}
{currentfile /ASCII85Decode filter /RunLengthDecode filter bstr readstring pop}
true 3
%%BeginData: 14759 ASCII Bytes
Any idea?
Answer
Finally after a lot of pain. I discover that the problem was the serial to USB cable (in order to connect the serial printer to an USB port). I tried with two different serial to USB cables, but the problem persists and finally I conclude that The printer works erratically if is not connect to a "real" serial port. I tested the printer under identical conditions in a PC with a serial port and it works perfect, just installing the driver provided by epson and giving chmod 777 to /dev/ttyS0. At the job list sometimes I see the error: "/usr/lib/cups/filter/pstopdf failed". But the printer prints ok, like no error occurred.