1 Software cursor for VGA 2 ======================= 3 4 by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz> 5 and Martin Mares <mj@atrey.karlin.mff.cuni.cz> 6 7 Linux now has some ability to manipulate cursor appearance. Normally, you 8 can set the size of hardware cursor (and also work around some ugly bugs in 9 those miserable Trident cards [#f1]_. You can now play a few new tricks: 10 you can make your cursor look 11 12 like a non-blinking red block, make it inverse background of the character it's 13 over or to highlight that character and still choose whether the original 14 hardware cursor should remain visible or not. There may be other things I have 15 never thought of. 16 17 The cursor appearance is controlled by a ``<ESC>[?1;2;3c`` escape sequence 18 where 1, 2 and 3 are parameters described below. If you omit any of them, 19 they will default to zeroes. 20 21 first Parameter 22 specifies cursor size:: 23 24 0=default 25 1=invisible 26 2=underline, 27 ... 28 8=full block 29 + 16 if you want the software cursor to be applied 30 + 32 if you want to always change the background color 31 + 64 if you dislike having the background the same as the 32 foreground. 33 34 Highlights are ignored for the last two flags. 35 36 second parameter 37 selects character attribute bits you want to change 38 (by simply XORing them with the value of this parameter). On standard 39 VGA, the high four bits specify background and the low four the 40 foreground. In both groups, low three bits set color (as in normal 41 color codes used by the console) and the most significant one turns 42 on highlight (or sometimes blinking -- it depends on the configuration 43 of your VGA). 44 45 third parameter 46 consists of character attribute bits you want to set. 47 48 Bit setting takes place before bit toggling, so you can simply clear a 49 bit by including it in both the set mask and the toggle mask. 50 51 .. [#f1] see ``#define TRIDENT_GLITCH`` in ``drivers/video/vgacon.c``. 52 53 Examples 54 -------- 55 56 To get normal blinking underline, use:: 57 58 echo -e '\033[?2c' 59 60 To get blinking block, use:: 61 62 echo -e '\033[?6c' 63 64 To get red non-blinking block, use:: 65 66 echo -e '\033[?17;0;64c' 67