sg(4)sg(4)Namesg - Small VAX color video subsystem
Syntax
device sg0 at uba0 csr 0x3c000000 flags 0x0f vector sgaint sgfint
Description
A small VAX color video subsystem provides a half-page or full-page,
user-accessible bitmap display for graphics applications. The device
consists of a 128-Kbyte block of dual port RAM, a VSXXX-AA mouse or
VSXXX-AB tablet, and a 19-inch video monitor.
The subsystem device driver supports a hybrid terminal with three minor
devices. The first device emulates a glass tty with a screen that
appears as a 120-column by 80-row page that scrolls from the bottom.
This device is capable of being configured as the system console.
The second minor device number is reserved for the mouse. This device
is a source of mouse state changes. (A state change is defined as an
X/Y axis mouse movement or button change.) When opened, the driver
couples movements of the mouse with the cursor. Mouse position changes
are filtered and translated into cursor position changes in an exponen‐
tial manner. Rapid movements result in large cursor position changes.
All cursor positions are range checked to ensure that the cursor
remains on the display.
The third minor device is opened in the raw mode by default. Opening
the third device makes the driver function like a pseudo-tty in that
the output destined for the first minor device is channeled to the
third instead.
If there is not a special cable (BCC08) on serial port 3 (printer
port), the system will then use the color video as the system console.
All input/output destined for will use the color video instead. (This
is done by overwriting the device switch tables.) There is a second
set of device switch entries configured that may be used as an addi‐
tional terminal, (hardwire, modem, or autodialer) connection, or user
dial-up access. For further information, see
The Hold Screen key is supported. The Small VAX color driver treats
this key as if CTRL/S or CTRL/Q is typed. Pressing the Hold Screen key
suspends the output if it is not already suspended. The output will be
resumed by pressing this key again (if the output was suspended).
FilesSee Alsoss(4), ttys(5), MAKEDEV(8)
VAX sg(4)