ISV(4) | Device Drivers Manual | ISV(4) |
isv
—
isv0 at isa? port 0x2f0
isv0 at isa? port 0x2e0
isv0 at isa? port 0x3f0
isv0 at isa? port 0x3e0
isv
is a driver for the IDEC Supervision/16, an image
capture board that plugs into a 16-bit ISA bus. The IDEC Supervision/16
digitizes an NTSC television signal, storing a 512 x 480-pixel, 8-bit
grayscale image in its 256kB dynamic RAM array every 1/30th of a second. The
host reads frames from the DRAM using 122881 16-bit I/O reads. Reading frames
from the Supervision/16 is quite slow: after the host reads a 16-bit word from
the DRAM, the Supervision/16 state machine takes approximately 0.5
microseconds to get ready for the next read. Theoretically, a frame rate of
approximately 10 frames per second is possible. isv
achieves a frame rate of approximately 6 frames per second.
Programming the Supervision/16 Image Capture Board, IDEC, circa 1991.
isv
device first appeared in NetBSD
5.0.
isv
driver was written by David
Young
<dyoung@NetBSD.org>.
isv
will not detect the capture board if
it is not attached to an active video source. To force
NetBSD to detect the capture board at any time,
re-scan the ISA bus using, e.g., drvctl
-r
isa0.
April 1, 2008 | NetBSD 9.4 |