134 To make these display as graphics characters each line must be preceded by (for example) code 146 (green graphics). So the following codes must be printed on the screen:
146, 250, 245 146, 255, 255 146, 191, 239 These codes can be sent using PRINT CHR$( ) as long as you are careful to get each code in the correct place, eg 10 MODE 7 20 X=20 30 Y=10 40 PRINT TAB(X,Y);CHR$(146);CHR$(154);CHR$(250);CHR$(245) 50 PRINT TAB(X,Y+1);CHR$(146);CHR$(154);CHR$(255);CHR$(255) 60 PRINT TAB(X,Y+2);CHR$(146);CHR$(154);CHR$(191);CHR$(239) Instead of using PRINT TAB (X,Y) it is probably easier in this case to use ASCII codes to move the cursor-down one line (code 10 ) and back four spaces (code 8 four times). It is probably also easier to use the VDU statement rather than PRINT CHR$ ( ) .
If these two things are done then the program becomes 5 MODE 7 6 PRINT TAB(20,10); 10 VDU 146,154,250,245 20 VDU 10,8,8,8,8 30 VDU 146,154,255,255 40 VDU 10,8,8,8,8 50 VDU 146,154,191,239 100 PRINT A complete list of the Teletext codes is given in Appemdix A and Appendix B. Teletext graphics codes for the more adventurous As you will have realised, the statements MOVE and DRAW are not available in the Teletext mode( MODE 7 ). If you wish to draw lines in this mode you will need to use a suitable procedure – so here is one. It uses a look-up table, called S% , to remember the numbers corresponding to each of the six pixels (picture elements) in a Teletext graphics character.
The look-up table must be set up at the beginning of the program: