38.3 UART signal descriptions
The UART signals are shown in the following table.
Table 38-1. UART signal descriptions
Signal
Description
I/O
RXD
Receive data
I
TXD
Transmit data
O
38.3.1 Detailed signal descriptions
The detailed signal descriptions of the UART are shown in the following table.
Table 38-2. UART—Detailed signal descriptions
Signal
I/O
Description
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.
38.4 Memory map and registers
This section provides a detailed description of all memory and registers.
Only byte accesses are supported.
UART memory map
Absolute
address
(hex)
Register name
Width
(in bits)
Access Reset value
Section/
page
4006_C000 UART Baud Rate Registers: High (UART2_BDH)
8
R/W
00h
Table continues on the next page...
UART signal descriptions
KL27 Sub-Family Reference Manual , Rev. 5, 01/2016
680
Freescale Semiconductor, Inc.
