jbm@eos.arc.nasa.gov (Jeffrey Mulligan) (05/17/89)
I am trying to synchronize the updating of a display on the SUN-4/110 console with the display refresh. In cgfour(4S), the following sentence appears in the discussion of the ioctl FBIOPUTCMAP: The driver uses color board vertical-retrace interrupts to load the color map. I had hoped that this ioctl would cause the program to hang until the retrace interval, but this does not seem to happen. I assume that the ioctl causes the color map change to be queued, and that the hardware gets loaded by the interrupt handler. I also turned up the following lines in /usr/include/sun/fbio.h : /* Vertical retrace support. */ #define FBIOVERTICAL _IOW(F, 9, int) What the heck is this for??? I tried calling ioctl with this code, and nothing happened (i.e., no delays, no data returned). I remember a few months back there was a long posting on undocumented features of the sun framebuffer from someone who was hacking their own operating system. I'm sure what I want to do can be done, but I'd like to do it in the approved fashion if possible. Jeff Mulligan (jbm@aurora.arc.nasa.gov) NASA/Ames Research Ctr., Mail Stop 239-3, Moffet Field CA, 94035 (415) 694-6290