Lines Matching +full:device +full:- +full:level

1 .\"-
2 .\" SPDX-License-Identifier: BSD-2-Clause
35 .Cd "device uart"
37 .Cd "device puc"
38 .Cd "device uart"
40 .Cd "device scc"
41 .Cd "device uart"
44 .Pa /boot/device.hints :
53 .Bl -tag -compact -width 0x000000
55 device is potential system console
59 set RX FIFO trigger level to ``low'' (NS8250 only)
61 set RX FIFO trigger level to ``medium low'' (NS8250 only)
63 set RX FIFO trigger level to ``medium high'' (default, NS8250 only)
65 set RX FIFO trigger level to ``high'' (NS8250 only)
71 device driver provides support for various classes of UARTs implementing the
72 EIA RS-232C (CCITT V.24) serial communications interface.
83 device drivers.
112 It contains the bus attachments and the low-level interrupt handler.
126 corresponding UART will in turn be a system device so that the kernel can
144 .Bl -bullet -compact
151 device driver.
160 is available on the tty device.
163 symlink the tty callout device
175 sysctl configures the PPS capture mode for a specific uart device;
182 .Bl -tag -compact -offset "mmmm" -width "mmmm"
193 .Bl -tag -compact -offset "mmmm" -width "mmmm"
195 Invert the pulse (RS-232 logic low = ASSERT, high = CLEAR).
214 Add the invert option when the connection to the uart device uses TTL
215 level signals, or when the PPS source emits inverted pulses.
216 RFC 2783 defines an ASSERT event as a higher-voltage line level, and a CLEAR
217 event as a lower-voltage line level, in the context of the RS-232 protocol.
218 The modem control signals on a TTL-level connection are typically
219 inverted from the RS-232 levels.
220 For example, carrier presence is indicated by a high signal on an RS-232
223 TTL and RS-232 line levels in most hardware designs.
224 Generally speaking, a connection to a DB-9 style connector is an RS-232
225 level signal at up to 12 volts.
226 A connection to header pins or an edge-connector on an embedded board
231 driver also supports an initial-state and a lock-state control
232 device for each of the callin and the callout "data" devices.
233 The termios settings of a data device are copied
234 from those of the corresponding initial-state device
238 in the normal way on the initial-state devices to program
245 on the lock-state device.
247 may be locked by setting the corresponding value in the lock-state
248 device to any nonzero value.
251 on the initial-state device and
253 on the lock-state device.
278 .Bl -tag -width indent
283 .Bl -tag -width indent
286 Enable the so-called
288 quirk for the device.
289 For NS 16550-compatible devices, this will use heuristics to ensure that the
291 DesignWare-based UARTs need this due to a design flaw in the UART.
295 When the device clock rate (see below) is set to 0, then the baud rate will be
296 used with the divisor to compute the device clock rate the first time the device
304 driver to not program the baud rate divisor and use the hardware as-is.
313 Device type.
314 Specify the uart class to use for this device.
315 .Bl -tag -width indent
328 Specifies the physical address of a memory-mapped UART.
344 Size of operations to read and write the registers of the device.
349 Device clock (xtal oscillator).
350 Base frequency of the oscillator to use for the device.
358 .Bl -tag -width "/dev/ttyu?.init" -compact
363 corresponding callin initial-state and lock-state devices
369 corresponding callout initial-state and lock-state devices
385 device driver first appeared in
390 device driver and this manual page were written by