Specifications

TH230/TH230+ Programmers Guide
47
• The driver has to send 148 nullbytes to the printer before the printer is
opened by the application. Thus it is guaranteed that the printer has left
the graphics function even if the graphics data stream was interrupted.
• If two-color paper is selected, two lines will be merged to one line. The
first line defines the secondary color (i.e. red) and second line defines the
primary color (black). is the For each printed dot row starting at the top
left, two-part bit strings are used to define (in the first half), all dots that
are of either color (i.e. not white). The second half string defines only the
dots where the color is black.
Caution: If two-color paper is selected, two lines for one line are exepted.
Der internal Buffer collects 256 lines. If one line missed, the whole buffer
will be restrained until the lost line or another command follows.
• If the compression bit is set by ESC * b m.
• If decompression activated, data bit will be decompressed with TIFF 4.0
Packbits Decompression.
• TIFF 4.0 Compression pseudo code:
for (all packed bytes)
{
n = next byte;
if (0 ≤ n ≤ 127)
Take on the next n+1 byte directly;
else // -128 ≤ n ≤ -1
Copy the next byte (-n+1)-times;
}
ESC * b m n
Function: Turn on/off TIFF compression
Code ASCII:
ESC * b m n
Code HEX: 0x1B 0x2A 0x62 0x6d n
Range: n = 0, 2, 48, 50
Default:
n = 0
Description: Turns the TIFF compression on (n = 2, 50) or off. (n = 0, 48).
Notes:
• Decompression is used by ESC * 1
• Decompression used TIFF 4.0 Packbits Decompression