CPU
SYSCLKOUT
Low speed
prescaler
System
control
block
PIE
block
RXINT
TXINT
Registers
SCI
SCIENCLK
LSPCLK
SCIRXD
SCITXD
GPIO
MUX
D
a
ta B
u
s
SYSRS
Enhanced SCI Module Overview
980
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
C28 Serial Communications Interface (SCI)
13.1 Enhanced SCI Module Overview
The SCI interfaces are shown in
Figure 13-1. SCI CPU Interface
Features of the SCI module include:
•
Two external pins:
–
SCITXD: SCI transmit-output pin
–
SCIRXD: SCI receive-input pin
Both pins can be used as GPIO if not used for SCI.
•
Baud rate programmable to 64K different rates
•
Data-word format
–
One start bit
–
Data-word length programmable from one to eight bits
–
Optional even/odd/no parity bit
–
One or two stop bits
•
Four error-detection flags: parity, overrun, framing, and break detection
•
Two wake-up multiprocessor modes: idle-line and address bit
•
Half- or full-duplex operation
•
Double-buffered receive and transmit functions
•
Transmitter and receiver operations can be accomplished through interrupt- driven or polled algorithms
with status flags.
•
Separate enable bits for transmitter and receiver interrupts (except BRKDT)
•
NRZ (non-return-to-zero) format
•
13 SCI module control registers located in the control register frame beginning at address 7050h
All registers in this module are 8-bit registers that are connected to Peripheral Frame 2. When a
register is accessed, the register data is in the lower byte (7
−
0), and the upper byte (15
−
8) is read as
zeros. Writing to the upper byte has no effect.
Enhanced features: