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UART Modules
32-5
Freescale Semiconductor
32.3.1
UART Mode Registers 1 (UMR1
n
)
The UMR1
n
registers control UART module configuration. UMR1
n
can be read or written when the mode
register pointer points to it, at RESET or after a
RESET
MODE
REGISTER
POINTER
command using
UCR
n
[MISC]. After UMR1
n
is read or written, the pointer points to UMR2
n
.
Address: 0xFC06_0000 (UMR10)
0xFC06_4000 (UMR11)
0xFC06_8000 (UMR12)
Access: User read/write
7
6
5
4
3
2
1
0
R
RXRTS
RXIRQ/
FFULL
ERR
PM
PT
B/C
W
Reset:
0
0
0
0
0
0
0
0
1
After UMR1
n
is read or written, the pointer points to UMR2
n
Figure 32-3. UART Mode Registers 1 (UMR1
n
)
Table 32-3. UMR1
n
Field Descriptions
Field
Description
7
RXRTS
Receiver request-to-send. Allows the U
n
RTS output to control the U
n
CTS input of the transmitting device to prevent
receiver overrun. If the receiver and transmitter are incorrectly programmed for U
n
RTS control, U
n
RTS control is
disabled for both. Transmitter RTS control is configured in UMR2
n
[TXRTS].
0 The receiver has no effect on U
n
RTS.
1 When a valid start bit is received, U
n
RTS is negated if the UART's FIFO is full. U
n
RTS is reasserted when the
FIFO has an empty position available.
6
RXIRQ/
FFULL
Receiver interrupt select.
0 RXRDY is the source generating interrupt or DMA requests.
1 FFULL is the source generating interrupt or DMA requests.
5
ERR
Error mode. Configures the FIFO status bits, USR
n
[RB,FE,PE].
0 Character mode. The USR
n
values reflect the status of the character at the top of the FIFO. ERR must be 0 for
correct A/D flag information when in multidrop mode.
1 Block mode. The USR
n
values are the logical OR of the status for all characters reaching the top of the FIFO since
the last
RESET
ERROR
STATUS
command for the UART was issued. See
.”
4–3
PM
Parity mode. Selects the parity or multidrop mode for the UART. The parity bit is added to the transmitted character,
and the receiver performs a parity check on incoming data. The value of PM affects PT, as shown below.
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 ...