Compuprint MDP40B Programmer Manual - Manual (Page 76)

A-74
ESC =
Defines downloaded characters.
(IBM Proprinter XL24/XL24E, 2391+)
ASCII Code ESC = n m id p t
Hexadecimal Value 1B 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:
• Copy the character generator in ROM into RAM
• 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 alphanumerical 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.