Compuprint 4247-L03 Programmer Manua - Manual (Page 54)

n Selection n Selection
2 Courier 1 Gothic
4 Script 5 OCR-B
6 OCR-A
182 DLL
Before copying ROM characters to RAM, cancel italics with the ESC 5 command. After copying you can
italicize characters by sending the ESC 4 command.
ESC =
Defines downloaded characters. (IBM)
ASCII Code ESC = n m id p t
Hexadecimal Value X'1B' X'3D' n m id p t
Decimal Value 27 61 n m id p t
This sequence allows you to design and then down-line load special characters not present in the
character set in use. Whenever you would like to start the DLL setting procedure, proceed as follows:
v Copy the character generator in ROM into RAM
v Select the DLL generator
There are 256 entries of 9 bytes that compose the look up table of a character generator. One entry
describes one character as follows:
Byte 1, 2 The absolute address of the character definition.
Byte 3 :
Bit 7
1: indicates that the character is a graphic character (connects at 6 lpi)
0: indicates that the character is an alphanumeric character
Bit 6
0: indicates a DLL character
1: indicates a resident character
Bit 5 to 0 These 6 bits indicate the effective number of dot columns of the character
shape stored in memory.
Byte 4: Graphic character description:
v 0: shading character
v 1: line drawing character
v 10: underscored character
v 11: not supported
All graphics characters are 30 dots high. An underscored character is
defined as a blank graphic (all zeros) and it is automatically generated by
the printer. A shading character repeats dots 1—6 of each column as dots
25 through 30 respectively. A line drawing character repeats dots 23 and
24 as the pairs 25 and 26, 27 and 28, 29 and 30.
Bit 5 to 0 The number of dot columns of the character shape minus one. For
example, the character width of Draft generator is 10 dots and bit 5 to 0
must be set to 9.
38 Programmer Manual