em78f644nso28s ELAN Microelectronics Corp, em78f644nso28s Datasheet - Page 45

• Manufacturer Part Number: em78f644nso28s
• Description: Flash Series 8-bit Microcontroller
• Manufacturer: ELAN Microelectronics Corp

Product Specification (V1.0) 05.05.2010
(This specification is subject to change without further notice)
6.1.32 Bank 2 RD URRD (UART_RD Data Buffer)
Bits 7 ~ 0 (URRD7 ~ URRD0): UART receive data buffer. Read only.
6.1.33 Bank 2 RE URTD (UART_TD Data Buffer)
Bits 7 ~ 0 (URTD7 ~ URTD0): UART transmit data buffer. Write only.
6.1.34 Bank 2 RF (Pull-high Control Register 1)
Bit 7 (/PH77): Control bit used to enable pull-high on the P77 pin
Bit 6 (/PH76): Control bit used to enable pull-high on the P76 pin.
Bit 5 (/PH75): Control bit used to enable pull-high on the P75 pin.
Bit 4 (/PH74): Control bit used to enable pull-high on the P74 pin.
Bit 3 (/PH73): Control bit used to enable pull-high on the P73 pin.
Bit 2 (/PH72): Control bit used to enable pull-high on the P72 pin.
Bits 1 ~ 0:
URRD7
URTD7
/PH77
Bit 7
Bit 7
Bit 7
The RF Register is both readable and writable.
For F642/542N, Bit 6 ~ Bit 5, Bit 3 ~ Bit 0 are unused. Set to “1” all the time.
For F641/541N, Bit 7 ~ Bit 0 are unused. Set to “1” all the time.
URRD6
URTD6
/PH76
Bit 6
Bit 6
Bit 6
Not used, set to “1” all the time.
0: Enable internal pull-high
1: Disable internal pull-high
For F642/542N, F641/541N, this register is reserved.
For F642/542N, F641/541N, this register is reserved.
URRD5
URTD5
/PH75
Bit 5
Bit 5
Bit 5
EM78F648/644/642/641/548/544/542/541N
URRD4
URTD4
/PH74
Bit 4
Bit 4
Bit 4
NOTE
NOTE
NOTE
URRD3
URTD3
/PH73
Bit 3
Bit 3
Bit 3
URRD2
URTD2
/PH72
Bit 2
Bit 2
Bit 2
8-Bit Microcontroller
URRD1
URTD1
Bit 1
Bit 1
Bit 1
“1”
URRD0
URTD0
Bit 0
Bit 0
Bit 0
“1”
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