Nxp Semiconductors UM10237 ユーザーズマニュアル
UM10237_2
© NXP B.V. 2008. All rights reserved.
User manual
Rev. 02 — 19 December 2008
433 of 792
NXP Semiconductors
UM10237
Chapter 16: LPC24XX Universal Asynchronous Receiver/Transmitter
4.9 UARTn Scratch Pad Register (U0SCR - 0xE000 C01C, U2SCR -
0xE007 801C U3SCR - 0xE007 C01C)
The UnSCR has no effect on the UARTn operation. This register can be written and/or
read at user’s discretion. There is no provision in the interrupt interface that would indicate
to the host that a read or write of the UnSCR has occurred.
read at user’s discretion. There is no provision in the interrupt interface that would indicate
to the host that a read or write of the UnSCR has occurred.
4.10 UARTn Auto-baud Control Register (U0ACR - 0xE000 C020, U2ACR -
0xE007 8020, U3ACR - 0xE007 C020)
The UARTn Auto-baud Control Register (UnACR) controls the process of measuring the
incoming clock/data rate for the baud rate generation and can be read and written at
user’s discretion.
incoming clock/data rate for the baud rate generation and can be read and written at
user’s discretion.
Table 388: UARTn Scratch Pad Register (U0SCR - address 0xE000 C01C,
U2SCR - 0xE007 801C, U3SCR - 0xE007 C01C) bit description
Bit Symbol Description
Reset
Value
Value
7:0 Pad
A readable, writable byte.
0x00
Table 389: UARTn Auto-baud Control Register (U0ACR - 0xE000 C020, U2ACR - 0xE007 8020,
U3ACR - 0xE007 C020) bit description
Bit
Symbol
Value Description
Reset value
0
Start
This bit is automatically cleared after auto-baud
completion.
completion.
0
0
Auto-baud stop (auto-baud is not running).
1
Auto-baud start (auto-baud is running).Auto-baud run
bit. This bit is automatically cleared after auto-baud
completion.
bit. This bit is automatically cleared after auto-baud
completion.
1
Mode
Auto-baud mode select bit.
0
0
Mode 0.
1
Mode 1.
2
AutoRestart 0
No restart.
0
1
Restart in case of time-out (counter restarts at next
UART0 Rx falling edge)
UART0 Rx falling edge)
0
7:3
-
NA
Reserved, user software should not write ones to
reserved bits. The value read from a reserved bit is not
defined.
reserved bits. The value read from a reserved bit is not
defined.
0
8
ABEOIntClr
End of auto-baud interrupt clear bit (write only
accessible). Writing a 1 will clear the corresponding
interrupt in the UnIIR. Writing a 0 has no impact.
accessible). Writing a 1 will clear the corresponding
interrupt in the UnIIR. Writing a 0 has no impact.
0
9
ABTOIntClr
Auto-baud time-out interrupt clear bit (write only
accessible). Writing a 1 will clear the corresponding
interrupt in the UnIIR. Writing a 0 has no impact.
accessible). Writing a 1 will clear the corresponding
interrupt in the UnIIR. Writing a 0 has no impact.
0
31:10 -
NA
Reserved, user software should not write ones to
reserved bits. The value read from a reserved bit is not
defined.
reserved bits. The value read from a reserved bit is not
defined.
0