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5.2.1.4
ESC
*
When this code is received in the case of 7-bit code, the expanded CG RAM (High) area is selected.
Characters AOH to FEH can be used as characters 20H to 7EH in a virtual manner.
If
this code is used while 8-bit code is in effect, only normal ROM characters (not down loaded
characters) with codes 20H- FEH can be designated.
5.2.2 Expanded CG Character Load (Down Load)
This control code is ESC
@,
and is used to code and load the character patterns, which the user
prepared, into the expanded CG RAM area.
The parameters used in this control code are shown below.
• ESC
@
:
Down Load control code
• (n)
: Selection of DP (Data Processing Mode) or LQ (Letter Quality Mode)
For the detail of n values, see the page 5-26
• xx
: Selects the character code number to load
• nn
: Selects the character code length to load
• mm
: Selects the amount of space both preceding and following the character
to be downloaded
• ddl, dd2-ddn
: Character data to load
• EOT
: Loaj Terminator code (end of text)
E S C
@
(n) xx nn mm ddl dd2 ddnn E 0 T
(n) :
Selection of DP or LQ
1
Byte
xx :
Code
1
Byte
nn :
Length
1
Byte
mm :
Space
1
Byte
ddl dd2 dd3 :
Data
nn
Bytes
5.2.2.1
Length
Length is the length of data, combining the number of dot columns with descender control.
Firstly, the descender control flag is explained.
Some letters such as
j
and g have a part which descends below the main body of the letter, and
are called descending characters.
With this printer, the DP character is printed by a CG pattern with 7 vertical dots, and the LQ
character by a CG pattern with 13 vertical dots. On the other hand, the aforementioned charac-
ters are actually printed with 9 vertical dots in the case of DP, and with 17 vertical dots in the
case of
LQ.
Thus, before printing, the flags assigned to the 7th and 6th bits of length, determine
whether descending is carried out. Such flags are called descender control flags.
The following figure shows length; the number of horizontal dots of the actual pattern is as-
signed to bits 5 to 0, and descender control flags to bits 7 and 6.
5-27
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