SP-401 User Manual
Telpar, Inc.
Page 12 of 25
5 Programming Information
5.1 General
The SP-401 printers have several different operation modes. Standard
printers can print text and dot addressable graphics.
5.2 Printable Characters
When the SP-401 printers are initially powered up and placed on-line, their
default mode is to process incoming data as ASCII text characters and print them
out in the normal font. The standard printable character set is listed in Appendix A
of this manual.
5.3 Graphics Mode
The SP-401 Series printers can print dot addressable graphics. There is a
mechanism dedicated for graphics use which allows the dot lines to connect
vertically after a line feed. Please contact Telpar for details on this optional
mechanism. The host computer controls each dot printed and each dot directly
corresponds to one bit of a graphics byte.
The following sequence must be sent to the printer at the beginning of each
line of graphics.
ESC+”S”+n1+n2+n3+n4 (256 Dot per Line)
The sequence ESC+”S” enables the graphics mode. The length of the bit
image data is declared by the digits n1, n2, n3, n4. The printer will return to the
character mode once the number of graphics characters has been printed.
Graphics data sent after the maximum number of columns has been reached will
be truncated.
An example of graphics where 192 bytes of bit image data are input as
follows:
1BH, 53H, 30H, 31H, 39H, 32H, = ESC+”S”+0+1+9+2
The relationship between graphics data and the printer dot head is as follows:
Print Head
Graphics Data
1 (Top)
DO (LSB)
2
D1
3
D2
4
D3
5
D4
6
D5
7
D6
8 (Bottom)
D7 (MSB on graphics models only)
