CognitiveTPG A798 Programming Manual page 45

Revision D 10/13
Chapter 4: Programming Commands 45
Formulas
To move to the left:
Determine the value of n by multiplying the number of columns to move left of the current position by 10 (standard) or
8 (compressed) pitch. The example shows how to set the relative position two columns in standard pitch (10 dots per
column) to the left of the current position.
2 x 10 = 20 dots (two columns to be moved left of the current position)
65,536–20 = 65516
65,516/256 = 255, remainder of 236
n1 = 236, n2 = 255
To move to the right:
Determine the value of n by multiplying the number of columns to move right of the current position by 10 (standard)
or 8 (compressed) pitch. The example shows how to set the relative position two columns in standard pitch (10 dots per
column) to the right of the current position.
2 x 10 = 20 dots (two columns to be moved left of the current position)
20/256 = 0, remainder of 20
n1 = 20, n2 = 0
Related information
If the set horizontal and vertical minimum motion units command (1D 50) is used to change the horizontal and vertical
minimum motion unit, the parameters of this command (set relative print position) will be interpreted accordingly. For
more information, see the description of the set horizontal and vertical minimum motion units command (1D 50) in this
document.
Compatibility information (A798 receipt vs. A793 receipt)
There is a difference in the normal behavior of this command in A793 emulation mode as compared to the original A793.
The difference exists when the command is used to move to the left. The A793 processes the whole print string prior to
putting it in the buffer for the print head. This method of processing allows the A793 to backup in the print string and
replace characters and their associated attributes when a "Set relative print position" command instructs the printer to
move the print position to the left.
Continued...
In order to improve the speed of printing, the A798 moves the data into a buffer for the printhead when it receives it.
When the "Set relative print position" command contains a move to the left, this causes the new data to overstrike the
previous data. This behavior can be used to an application's advantage to provide the ability to create compound characters
on the receipt station.
This command also functions differently in the A793 emulation when used in graphics:
n x 2 = Number of dots to be moved from the beginning of the line when this command is followed by a graphic command.
A798-PG00001D