UART Modules
Freescale Semiconductor
32-14
NOTE
True status is provided in the UISR
n
regardless of UIMR
n
settings. UISR
n
is cleared when the UART module is reset.
Address: 0xFC06_0014 (UISR0)
0xFC06_4014 (UISR1)
0xFC06_8014 (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 32-12. UART Interrupt Status/Mask Registers (UISR
n
/UIMR
n
)
Table 32-10. 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 U
n
CTS 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 32.3.5, “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] and 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 is cleared 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
Summary of Contents for MCF54455
Page 33: ...xxviii Freescale Semiconductor ...
Page 67: ...Freescale Semiconductor 1 ...
Page 125: ...Freescale Semiconductor 1 ...
Page 145: ...Enhanced Multiply Accumulate Unit EMAC 5 21 Freescale Semiconductor ...
Page 173: ...Cache 6 28 Freescale Semiconductor ...
Page 179: ...Static RAM SRAM 7 6 Freescale Semiconductor ...
Page 207: ...Power Management 9 16 Freescale Semiconductor ...
Page 323: ...Reset Controller Module 13 8 Freescale Semiconductor ...
Page 389: ...Pin Multiplexing and Control 16 44 Freescale Semiconductor ...
Page 575: ...PCI Bus Controller 22 58 Freescale Semiconductor ...
Page 600: ...Advanced Technology Attachment ATA Freescale Semiconductor 23 25 ...
Page 601: ...Freescale Semiconductor 1 ...
Page 842: ...I2 C Interface Freescale Semiconductor 33 16 ...
Page 843: ...Freescale Semiconductor 1 ...
Page 921: ...Revision History A 6 Freescale Semiconductor ...