Print text.

Hello, mig'95 mig> Please tell me how to organize printing mig> text on the screen is not RST 16. It is not necessary to provide the code here mig> just a general description of the algorithm is enough.. I myself have something in mig> difficulty.. :v2_conf2: using x,y coordinates, calculate the address of the upper byte of the familiarity location, (*) take the code symbol, using the symbol code and font address, find the address of the first of the 8 bytes of graphics symbol. take a character byte, put it in the screen address, move on to the next one character byte and screen address one pixel lower, and so on 8 times. go to screen address for the next character, repeat all this, starting with (*), until until the line ends.

Hello, boo_boo Line by line will be faster. Those. first the top line of the entire line, then the second etc.

Hello, boo_boo boo> using the symbol code and font address, find the address of the first of 8 graphics bytes boo> character. This is completely unclear. Can you be more specific? For example, if I use standard font located at address 15616 (also, by the way, incomprehensible - after all to launch TR-DOS we contact from BASIC to this address, and there is the font) and I need to print a character, for example "H" (code 72).

Hello, mig'95 mig> For example, if I use a standard font located from the address mig> 15616 (also, by the way, it’s not clear - after all, to run TR-DOS we mig> we contact from BASIC to this address, and there is a font) and I need mig> print a character, for example "H" (code 72). Each character in ROM takes up 8 bytes. The font begins with a space character. His code - 32. This means the real beginning of the font, that is, the character with code 0, is located at 15616-32*8. To get the address of the letter "H" in a font you obviously need do this: (15616-32*8)+(72*8). The 8 bytes following this address will be components of the H symbol. As for TR-DOS, the Beta Disk controller is designed in such a way that when you try transition to a certain area of ROM addresses, which includes the mentioned address is 15616, the TR-DOS ROM is turned on, which replaces standard ROM with BASIC. And in the TR-DOS ROM at these addresses there are no longer font, and the program code for working with the drive.

Hello, CityAceE The general principle is this: Physical address of video memory: Address=16384+2048*I+32*J+256*K+X, where: I=0...2 - number of the third of the screen (from top to bottom); J=0...7 - number of the character line in the third (from top to bottom); K=0...7 - line number (byte) in the symbol (from top to bottom); X=0...31 - number of the familiar place in the line (from left to right).