NXP Semiconductors K22F series User Manual

Table 47-2. UART—Detailed signal descriptions (continued)
Signal I/O Description
Negation—When transmitting device's RTS deasserts.
RTS O Request to send. When driven by the receiver, indicates whether the UART is ready to
receive data. When driven by the transmitter, can enable an external transceiver during
transmission.
State
meaning
Asserted—When driven by the receiver, ready to receive data. When
driven by the transmitter, enable the external transmitter.
Negated—When driven by the receiver, not ready to receive data. When
driven by the transmitter, disable the external transmitter.
Timing
Assertion—Can occur at any time; can assert asynchronously to the other
input signals.
Negation—Can occur at any time; can deassert asynchronously to the
other input signals.
RXD I Receive data. Serial data input to receiver.
State meaning
Whether RXD is interpreted as a 1 or 0 depends on the bit encoding
method along with other configuration settings.
Timing
Sampled at a frequency determined by the module clock divided by the
baud rate.
TXD O Transmit data. Serial data output from transmitter.
State meaning
Whether TXD is interpreted as a 1 or 0 depends on the bit encoding
method along with other configuration settings.
Timing
Driven at the beginning or within a bit time according to the bit encoding
method along with other configuration settings. Otherwise, transmissions
are independent of reception timing.
47.3 Memory map and registers
This section provides a detailed description of all memory and registers.
Accessing reserved addresses within the memory map results in a transfer error. None of
the contents of the implemented addresses are modified as a result of that access.
Only byte accesses are supported.
UART memory map
Absolute
address
(hex)
Register name
Width
(in bits)
Access Reset value
Section/
page
4006_A000 UART Baud Rate Registers: High (UART0_BDH) 8 R/W 00h 47.3.1/1224
4006_A001 UART Baud Rate Registers: Low (UART0_BDL) 8 R/W 04h 47.3.2/1225
4006_A002 UART Control Register 1 (UART0_C1) 8 R/W 00h 47.3.3/1226
4006_A003 UART Control Register 2 (UART0_C2) 8 R/W 00h 47.3.4/1227
Table continues on the next page...
Chapter 47 Universal Asynchronous Receiver/Transmitter (UART)
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
NXP Semiconductors 1219

NXP Semiconductors K22F series Specifications

General

Brand	NXP Semiconductors
Model	K22F series
Category	Controller
Language	English