UART Modules
MCF52110 ColdFire® Integrated Microcontroller Reference Manual, Rev. 1
23-14
Freescale Semiconductor
Preliminary
NOTE
True status is provided in the UISR
n
regardless of UIMR
n
settings. UISR
n
is cleared when the UART module is reset.
IPSBAR
Offset:
0x00_0214 (UISR0)
0x00_0254 (UISR1)
0x00_0294 (UISR2)
Access: User read/write
7
6
5
4
3
2
1
0
R
(UISR
n
)
COS
0
0
0
0
DB
FFULL/
RXRDY
TXRDY
W
(UIMR
n
)
COS
0
0
0
0
DB
FFULL/
RXRDY
TXRDY
Reset:
0
0
0
0
0
0
0
0
Figure 23-12. UART Interrupt Status/Mask Registers (UISR
n
/UIMR
n
)
Table 23-10. UISR
n
/UIMR
n
Field Descriptions
Field
Description
7
COS
Change-of-state.
0 UIPCR
n
[COS] is not selected.
1 Change-of-state occurred on UCTS
n
and was programmed in UACR
n
[IEC] to cause an interrupt.
6–3
Reserved, must be cleared.
2
DB
Delta break.
0 No new break-change condition to report.
Section 23.3.5, “UART Command Registers (UCRn)
,” describes the
RESET
BREAK
-
CHANGE
INTERRUPT
command.
1 The receiver detected the beginning or end of a received break.
1
FFULL/
RXRDY
Status of FIFO or receiver, depending on UMR1[FFULL/RXRDY] bit. Duplicate of USR
n
[FIFO] & USR
n
[RXRDY]
0
TXRDY
Transmitter ready. This bit is the duplication of USR
n
[TXRDY].
0 The transmitter holding register was loaded by the CPU or the transmitter is disabled. Characters loaded into the
transmitter holding register when TXRDY equaling to 0 are not sent.
1 The transmitter holding register is empty and ready to be loaded with a character.
UIMR
n
[FFULL/RXRDY]
UISR
n
[FFULL/RXRDY]
UMR1
n
[FFULL/RXRDY]
0 (RXRDY)
1 (FIFO)
0
0
Receiver not ready
FIFO not full
1
0
Receiver not ready
FIFO not full
0
1
Receiver is ready,
Do not interrupt
FIFO is full,
Do not interrupt
1
1
Receiver is ready,
interrupt
FIFO is full,
interrupt