MAGMA(4) | Device Drivers Manual (sparc) | MAGMA(4) |
magma
— Magma Sp
Serial/Parallel board device driver
magma* at sbus? slot ? offset ?
mtty* at magma?
mbpp* at magma?
The magma
driver provides an interface to
Magma LC2+1Sp, 2+1Sp, 4+1Sp, 8+2Sp, 4Sp, 8Sp, 12Sp, 16Sp, 1P and 2P boards.
These boards are based around the Cirrus Logic CD1400 serial/parallel
communications engine and the Cirrus Logic CD1190 parallel communications
engine.
The device minor numbers for this driver are encoded as follows:
+---+---+---+---+---+---+---+---+ | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | +---+---+---+---+---+---+---+---+ | | | | | | | | | | | | +---+---+---+---> port number | | | | | | | +-------------------> dial-out (on tty ports) | | | | | +-----------------------> unused | | +---+---------------------------> card number
Up to four cards are supported in the system.
All tty ports have full automatic hardware (RTS/CTS) flow control available and a 12 byte FIFO on the chip in each direction so errors should be minimal.
If need be you can make the ring buffer bigger by changing the
MAGMA_RBUF_SIZE
#define to something bigger, but
it should be a multiple of two.
Reducing the value of either the
MTTY_RX_FIFO_THRESHOLD
or
MTTY_RX_DTR_THRESHOLD
#define's to something
smaller may help slow machines avoid this problem.
The driver was loosely based upon the cy(4) Cyclades Cyclom device driver written by Andrew Herbert and Timo Rossi.
The driver was written by Iain Hibbert.
CD1190 parallel support.
"bpp" input.
Dial-out (cua) devices are not yet supported.
"mdmbuf" is unsupported (see tty(4) and termios(4)).
Automatic XON/XOFF handshaking could be implemented fairly easily.
It would be good if the tty port waited for the FIFO to empty before allowing a close, so that I could turn off the channel interrupts at that time. It can be done.
April 21, 1998 | NetBSD 10.99 |