Specifications

CHAPTER 4
Software Support
Control and Status Calls 65
rsEnableVideo 4
You can use the rsEnableVideo control routine to enable the VGA display output. You
use this routine when you have a shared video monitor and want to switch it from the
Mac OS to the PC system.
The control call for this routine is rsEnableVideo = 705.
Parameter block
—> indicates input to the driver
<— indicates output from the driver
rsDisableVideo 4
You can use the rsDisableVideo control routine to disable the VGA display output
when the Macintosh video output is connected to the video connector. If the Macintosh
video is not connected, this call does nothing.
The control call for this routine is rsDisableVideo = 706.
4 1 = disk mounting enabled (rsDiskMountEnabled)
5 1 = shared memory enabled (rsSharedEnabled)
6 1 = DMA enabled (rsDMAEnabled)
7 1 = video cable enabled (rsCableInstalled)
8 1 = modem port is used by COM1
9 1 = printer port is used by COM1
10 1 = modem port is used by COM2
11 1 = printer port is used by COM2
24–31 Reserved
—> ioCompletion long Pointer to the completion routine.
<— ioResult word Device driver’s result code.
—> ioRefNum word Device driver’s reference number.
—> csCode word Equals rsEnableVideo.
Table 4-1 PC status word (continued)
Bit Meaning