pc87591l National Semiconductor Corporation, pc87591l Datasheet - Page 158

• Manufacturer Part Number: pc87591l
• Description: Lpc Mobile Embedded Controllers
• Manufacturer: National Semiconductor Corporation

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Embedded Controller Modules
4.9.4
For a summary of the abbreviations used for Register Type, see “Register Abbreviations and Access” on page 34.
USART Register Map
Receive Data Buffer Register (URBUF)
Location: 00 FD22
Type: RO
Transmit Data Buffer Register (UTBUF)
Location: 00 FD20
Type: R/W
Baud Rate Pre-Scaler Register (UPSR)
Byte-wide read/write register containing the 5-bit pre-scaler value in bit 7 (MSB) through bit 3 (LSB) and the upper three bits
of the baud divisor in bit 2 (MSB) through bit 0 (LSB). The register is cleared (00
Location: 00 FD2E
Type: R/W
Baud Rate Divisor Register (UBAUD)
This byte-wide read/write register contains the lower eight bits of the baud rate divisor. The UPSR register contains the upper
three bits. The register is cleared (00
Location: 00 FD2C
Type: R/W
Bit
Name
Bit
Name
Bit
Name
Reset
Bit
Name
Reset
USART Registers
16
16
16
16
7
7
7
0
7
0
URBUF
UTBUF
UPSR
UBAUD
UFRS
UMDSL
USTAT
UICTRL
Mnemonic
6
6
6
0
6
0
16
Receive Data Buffer Register
Transmit Data Buffer Register
Baud Rate Pre-Scaler Register
Baud Rate Divisor Register
Frame Select Register
Mode Select Register
Status Register
Interrupt Control Register
) on reset.
(Continued)
UPSC
5
5
5
0
5
0
Register Name
UDIV[7]: UDIV[0]
158
4
4
4
0
4
0
URBUF
UTBUF
3
3
3
0
3
0
16
) on reset.
Varies per bit
2
2
2
0
2
0
Type
R/W
R/W
R/W
R/W
R/W
RO
RO
UDIV[10]: UDIV[8]
1
1
1
0
1
0
Revision 1.07
0
0
0
0
0
0