Registers
1527
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Universal Asynchronous Receiver/Transmitter (UART)
Table 31-17. Line Status Register (LSR) Field Descriptions (continued)
Bit
Field
Value
Description
0
DR
Data-ready (DR) indicator for the receiver. If the DR bit is set and the corresponding interrupt enable bit
is set (ERBI = 1 in IER), an interrupt request is generated.
In non-FIFO mode:
0
Data is not ready, or the DR bit was cleared because the character was read from the receiver buffer
register (RBR).
1
Data is ready. A complete incoming character has been received and transferred into the receiver buffer
register (RBR).
In FIFO mode:
0
Data is not ready, or the DR bit was cleared because all of the characters in the receiver FIFO have
been read.
1
Data is ready. There is at least one unread character in the receiver FIFO. If the FIFO is empty, the DR
bit is set as soon as a complete incoming character has been received and transferred into the FIFO.
The DR bit remains set until the FIFO is empty again.