NTWOC(4) BSD Kernel Interfaces Manual NTWOC(4)NAME
ntwoc -- Riscom/N2, N2pci, WANic 400 synchronous serial interfaces
SYNOPSIS
ntwoc* at pci? dev ? function ? flags 0
ntwoc0 at isa? port 0x300 irq 5 iomem 0xc8000 flags 1
DESCRIPTION
The ntwoc device driver supports bit-synchronous serial communication using Cisco HDLC framing. The cards are capable of being driven by the
line clock or from an internal baud rate generator. The devices all use the Hitachi hd64570 serial chip. The hd64570 supports 2 asynchro-
nous/byte-synchronous/bit-synchronous serial ports, and has a 4-channel DMA controller for loading the serial port FIFOs.
The ISA Riscom/N2 card has a jumper block to set the IRQ and a DIP switch to set the port address the card will use. The values programmed
into the card must be specified with the port and irq locators in the kernel configuration line. The iomem locator must be specified and
must occur on a 16k boundary. The driver uses a 16k region of io memory. Bit 0 of the flags locator indicates if there is a second serial
port available on the card.
Currently clock source and speed information is specified with the flags locator in the kernel configuration file. The flags field has the
following format.
3 2 1
1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0
+-------------+ +-----+ +-----+ + +---+ +-+ + +---+ +-+ +
tmc tdiv rdiv e1 rxs1 ts1 e0 rxs0 txs0 np(*)
tmc Defines the timer constant. The base clock frequency is divided by tmc to generate the main clock for receiving and sending.
Further division is possible with the tdiv and rdiv divisor options. A value of 0 is treated as 256.
tdiv Defines the transmit divisor as 2^(tdiv). The internal transmit clock frequency is determined by dividing the base clock fre-
quency by tmc and then dividing by 2^(tdiv).
rdiv Defines the receive divisor as 2^(rdiv). The internal receive clock frequency is determined by dividing the base clock frequency
by tmc and then dividing by 2^(rdiv).
e0 e1 If true the internal clock source is used to drive the line clock for port 0 or port 1 respectively.
rxs0 rxs1 Specifies which clock source to use for receiving data on port 0 and port 1 respectively. The following values are accepted:
0
Line clock.
1
Line clock with noise suppression.
2
Internal clock.
txs0 txs1 Specifies which clock source to use for transmitting data on port 0 and port 1 respectively. The following values are accepted:
0
Line clock.
1
Internal clock.
2
Receive clock.
np (For the ISA card only) A value of 1 indicates there is a second serial port present on the card. This is auto-detected on the
PCI card and need not be specified.
HARDWARE
Cards supported by the ntwoc driver include:
SDL Communications Riscom/N2
SDL Communications N2pci
SDL Communications WANic 400 (untested)
DIAGNOSTICS
ntwoc0: TXDMA underrun - fifo depth maxed Indicates that the serial port's FIFO is being drained faster than DMA can fill it. The driver
automatically increases the low-water mark at which to begin DMA transfers when underruns occur. This diagnostic is issued when the low-
water mark is maximized (i.e., 1 less than the depth of the FIFO).
ntwoc0: RXDMA buffer overflow Indicates that a frame is being received by the card, but there are no free receive buffers.
SEE ALSO intro(4), isa(4), pci(4), ifconfig(8)HISTORY
The PCI driver first appeared in NetBSD 1.4. Much of the ISA driver was adapted from the FreeBSD sr driver and first appeared in NetBSD 1.5.
BUGS
Use of the flags locator for setting the clock sources and speeds should be replaced with ioctl's and a control program.
BSD October 2, 1998 BSD
Check Out this Related Man Page
syncinit(1M) System Administration Commands syncinit(1M)NAME
syncinit - set serial line interface operating parameters
SYNOPSIS
/usr/sbin/syncinit device [ [baud_rate] | [keyword=value,...] | [single-word option]]
DESCRIPTION
The syncinit utility allows the user to modify some of the hardware operating modes common to synchronous serial lines. This can be useful
in troubleshooting a link, or necessary to the operation of a communications package.
If run without options, syncinit reports the options as presently set on the port. If options are specified, the new settings are reported
after they have been made.
OPTIONS
Options to syncinit normally take the form of a keyword, followed by an equal sign and a value. The exception is that a baud rate may be
specified as a decimal integer by itself. Keywords must begin with the value shown in the options table, but may contain additional letters
up to the equal sign. For example, loop= and loopback= are equivalent.
The following options are supported:
Keyword Value Effect
loop yes Set the port to operate in internal
loopback mode. The receiver is elec-
trically disconnected from the DCE
receive data input and tied to the
outgoing transmit data line. Transmit
data is available to the DCE. The Dig-
ital Phase-Locked Loop (DPLL) may not
be used as a clock source in this
mode. If no other clocking options
have been specified, perform the
equivalent of txc=baud and rxc=baud.
no Disable internal loopback mode. If no
other clocking options have been spec-
ified, perform the equivalent of
txc=txc and rxc=rxc.
echo yes Set the port to operate in auto-echo
mode. The transmit data output is
electrically disconnected from the
transmitter and tied to the receive
data input. Incoming receive data is
still visible. Use of this mode in
combination with local loopback mode
has no value, and should be rejected
by the device driver.
The auto-echo mode is useful to make
a system become the endpoint of a
remote loopback test.
no Disable auto-echo mode.
nrzi yes Set the port to operate with NRZI data
encoding.
no Set the port to operate with NRZ data
encoding.
txc txc Transmit clock source will be the TxC
signal (pin 15).
rxc Transmit clock source will be the RxC
signal (pin 17).
baud Transmit clock source will be the
internal baud rate generator.
pll Transmit clock source will be the out-
put of the DPLL circuit.
rxc rxc Receive clock source will be the RxC
signal (pin 17).
txc Receive clock source will be the TxC
signal (pin 15).
baud Receive clock source will be the
internal baud rate generator.
pll Receive clock source will be the out-
put of the DPLL circuit.
speed integer Set the baud rate to integer bits per
second.
There are also several single-word options that set one or more paramaters at a time:
Keyword Equivalent to Options:
external txc=txc rxc=rxc loop=no
sender txc=baud rxc=rxc loop=no
internal txc=pll rxc=pll loop=no
stop speed=0
EXAMPLES
Example 1: Using syncinit
The following command sets the first CPU port to loop internally, using internal clocking and operating at 38400 baud:
example# syncinit zsh0 38400 loop=yes
device: /dev/zsh ppa: 0
speed=38400, loopback=yes, echo=no, nrzi=no, txc=baud, rxc=baud
The following command sets the same port's clocking, local loopback and baud rate settings to their default values:
example# syncinit zsh0 stop loop=no
device: /dev/zsh ppa: 0
speed=0, loopback=no, echo=no, nrzi=no, txc=txc, rxc=rxc
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
+-----------------------------+-----------------------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+-----------------------------+-----------------------------+
|Availability |SUNWcsu |
+-----------------------------+-----------------------------+
SEE ALSO syncloop(1M), syncstat(1M), intro(2), ioctl(2), attributes(5), zsh(7D)DIAGNOSTICS
device missing minor device number The name device does not end in a decimal number that can be used as a minor device number.
bad speed: arg The string arg that accompanied the speed= option could not be interpreted as a decimal integer.
Bad arg: arg The string arg did not make sense as an option.
ioctl failure code = errno An ioctl(2) system called failed. The meaning of the value of errno may be found in intro(2).
WARNINGS
Do not use syncinit on an active serial link, unless needed to resolve an error condition. Do not use this command casually or without
being aware of the consequences.
SunOS 5.10 9 Mar 1993 syncinit(1M)