
SCI Control Registers
1359
SPNU503C – March 2018
Copyright © 2018, Texas Instruments Incorporated
Serial Communication Interface (SCI) Module
26.7.12.3 Transmit Data Buffer Register (SCITD)
Data to be transmitted is written to the SCITD register.
and
illustrate this
register.
NOTE:
Data written to the SCITD register that is fewer than eight bits long must be right justified, but
it does not need to be padded with leading zeros.
Figure 26-21. Transmit Data Buffer Register (SCITD) [offset = 38h]
31
16
Reserved
R-0
15
8
7
0
Reserved
TD
R-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 26-20. Transmit Data Buffer Register (SCITD) Field Descriptions
Bit
Field
Value
Description
31-8
Reserved
0
Reads return 0. Writes have no effect.
7-0
TD
0-FFh
Transmit data. Data to be transmitted is written to the SCITD register. The transfer of data from
this register to the transmit shift register SCITXSHF sets the TXRDY flag, which indicates that
SCITD is ready to be loaded with another byte of data.
Note: If TX INT ENA is set, this data transfer also causes an interrupt.
26.7.13 SCI Pin I/O Control Register 0 (SCIPIO0)
and
illustrate this register.
Figure 26-22. SCI Pin I/O Control Register 0 (SCIPIO0) [offset = 3Ch]
31
8
Reserved
R-0
7
3
2
1
0
Reserved
TX FUNC
RX FUNC
Reserved
R-0
R/W-0
R/W-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 26-21. SCI Pin I/O Control Register 0 (SCIPIO0) Field Descriptions
Bit
Field
Value
Description
31-3
Reserved
0
Reads return 0. Writes have no effect.
2
TX FUNC
Transfer function. This bit defines the function of pin SCITX.
0
SCITX is a general-purpose digital I/O pin.
1
SCITX is the SCI transmit pin.
1
RX FUNC
Receive function. This bit defines the function of pin SCIRX.
0
SCIRX is a general-purpose digital I/O pin.
1
SCIRX is the SCI receive pin.
0
Reserved
0
Reads return 0. Writes have no effect.