HEIDENHAIN SHB Data Interfaces for HEIDENHAIN - Manual (Page 44)

April 2010 6 – 45
Machine parameter calculation for graphic output
In the graphics mode the display of the TNC 155/355 consists of 512 x 490 pixels. For graphic
data output, the data is output line by line in 8-bit format via the serial interface. A line consists
of 8 pixels and 512 bytes.
The parameters are subdivided into two blocks:
The first block (MP 226 (5110.0) to MP 229 (5110.3)) is sent once before each block.
It serves to initialize the printer and to set the general parameters for graphic output,
e.g. line spacing, carriage return, line feed and possibly form feed to reach the beginning of
the print paper.
The line feed must be specified such that the graphic lines are printed without blanks in
between. For this reason, the line spacing should be 72/216 inches.
The second parameter block (MP 230 (5120.0) to MP 233 (5120.3)) is output before each graphic
line to perform carriage return and line feed at the printer and to set it to the graphics mode.
The control outputs 512 data bytes per line, i.e. 512 bytes must be displayed as graphics on
paper before the printer automatically switches from the graphics mode to ASCII mode.
The commands for the printer are described in escape sequences which may vary from
printer to printer.
The EPSON command set for printers is a quasi-standard supported by most printer
manufacturers. Therefore, this manual refers to these EPSON ESCAPE SEQUENCES.