J.P. SELECTA ST DRY PV 12 Manual De Instrucciones página 36

3.17【Set the gray degree】
Format: ASCII:
Dec:
Hex:
N ranges from 0 to 12, the larger of the n value, the darker the dot it is. The
initial n=7. It is used to modify the final expression of different thermal paper
roll.
3.18【Turn underline mode on/off】
[Format] ASCII
Hex
Decimal
[Description] Turns underline mode on or off, based on the following
values of n.
0: Turns off underline mode, 1: Turns on underline mode.
[Notes] W hen turn white/black reverse printing mode, the underline is not
effective.
Changing the character size can affect the current underline thickness.
Underline mode can also be turned on or off by using ESC !.
Note, however, that the last received command is effective.
[Default] n = 0
3.19【Turn white/black reverse printing mode】
[Format] ASCII
Hex
Decimal 29 66
[Range] 0 n

[Description]
When the LSB of n is 0, white/black reverse mode is turned off.
When the LSB of n is 1, white/black reverse mode is turned on.
[Notes] Only the lowest bit of n is valid.
When white/black reverse printing mode is on, it also applies to
character spacing set by ESC SP.
This command does not affect bit images, user‐defined bit images,
ESC $, and ESC \.
This command does not affect the space between lines.
White/black reverse mode has a higher priority than underline mode.
Even if underline mode is on, it is disabled (but not canceled)
when white/black reverse mode is selected.
ESC M
27 109
1B 6D
ESC
1B
27
GS B n
1D 42 n
n
255

Turn on or off white/black reverse printing mode.
n
n
n
‐ n
2D n
45 n
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