Lines Matching +full:hardware +full:- +full:fifo

1 .\"-
2 .\" SPDX-License-Identifier: BSD-2-Clause
53 .Bl -tag -compact -width 0x000000
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)
72 EIA RS-232C (CCITT V.24) serial communications interface.
102 driver has a modular design to allow it to be used on differing hardware and
112 It contains the bus attachments and the low-level interrupt handler.
114 .Ss HARDWARE DRIVERS
115 The core component and the kernel interfaces talk to the hardware through the
116 hardware interface.
117 This interface serves as an abstraction of the hardware and allows varying
121 System devices are UARTs that have a special purpose by way of hardware
139 .Sh HARDWARE
144 .Bl -bullet -compact
146 NS8250: standard hardware based on the 8250, 16450, 16550, 16650, 16750 or
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).
202 In narrow mode the driver uses the hardware's ability to latch a line
203 state change; not all hardware has this capability.
204 The hardware latch provides a reliable indication that a pulse occurred,
208 To prevent spurious events when the hardware is intermittently able to
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
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
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
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
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.
304 driver to not program the baud rate divisor and use the hardware as-is.
315 .Bl -tag -width indent
328 Specifies the physical address of a memory-mapped UART.
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