QNX RTOS v4 Knowledge Base
QNX RTOS v4 Knowledge Base
| Title |
Setting text colour attributes from code |
| Ref. No. |
QNX.000001700 |
| Category(ies) |
Development |
| Issue |
I am using console write, and I would like to have different colours, cursor control and specifically bright backgrounds. By default, the video card is set for blinking foreground, not bright background. This is an attribute bit in the mode control register on the VGA card.
How to get these attributes from code?
|
| Solution |
Here is a sample application, showing the input and output stuff for toggling the hardware display abilities.
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/console.h>
#include <conio.h>
#define BRIGHT 0
#define BLINK 1
void set_blink_bit(int mode)
{
unsigned short val;
inp(0x3da); // an IN to 0x3da (VGA) clears the 0x3c0 flip flop
outp(0x3c0,0x10); // load the control register with the reg num
val = inp(0x3c1); // grab the reg num value for later restore
outp(0x3c1, 0x20); // give control of the register back (set bit 0x20)
if(mode == BRIGHT)
val &= ~0x08; // bit 3 of the 0x10 register toggles blink/bright
if(mode == BLINK)
val |= 0x08; // bit 3 of the 0x10 register toggles blink/bright
inp(0x3da); // an IN to 0x3da (VGA) clears the 0x3c0 flip flop
outp(0x3c0,0x10); // load the control register with the reg num
outp(0x3c0, val);
outp(0x3C0, 0x20); // give control of the register back (set bit 0x20)
inp(0x3DA); // clear the flip flop - leave a happy state.
} |
|
