Cmsemicon CMS32L051 - 12.2 Structure of universal serial communication unit

V1.2.2
CMS32L051 User Manual |Chapter 12 Universal Serial Communication Unit
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12.2 Structure of universal serial communication unit
The universal serial communication unit consists of the following hardware.
Table 12-1 Structure of universal serial communication unit
Project
Structure
Shift register
8-bit or 9-bit
Note 1
Buffer register
The serial data register mn (SDRmn) is 8 bits low or 9 bits
Note 1 and 2
Serial clock input/output
SCLK00, SCLK01, SCLK10, SCLK11, SCLK20, SCLK21 pins (for 3-wire serial I/O).
SCL00, SCL01, SCL10, SCL11, SCL20, SCL21 pins (for Easy I
2
C)
Serial data input
SDI00, SDI01, SDI10, SDI11, SDI20, SDI21 pins (for 3-wire serial I/O),
RxD0, RxD1, RxD2 pins (for UART).
Serial data output
SDO00, SDO01, SDO10, SDO11, SDO20, SDO21 pins (for 3-wire serial I/O),
TxD0, TxD1, TxD2 pins (for UART).
Serial data input/output
SDA00, SDA01, SDA10, SDA11, SDA20, SDA21 pins (for Simplified I
2
C)
Slave Select Input
SS00 pin (for slave select input function).
Control registers
< Register of Unit Setting Section >
 0 (PER0).
 m (SPSm).
enable status register m (SEm).
 m (SSm).
 m (STm).
 m (SOEm).
 m (SOm).
 m (SOLm).
switch control register (ISC).
enable register 0 (NFEN0).
< register for each channel >
 mn (SDRmn).
 mn (SMRmn).
operation setting register mn (SCRmn).
 mn (SSRmn).
 mn (SIRmn).
Port multiplexing function configuration register (PxxCFG).
output mode register (POMxx).


Note 1 The number of bits used as shift registers and buffer registers varies by unit and channel.
= 00, 01: low 9-bit
Others: low 8-bit
2. Depending on the communication mode, the lower 8 bits of the serial data register mn (SDRmn) can be read and
written with the following SFR name.
 SSPIp communication... SIOp (SSPIp Data Register).
 UARTq receives... RXDq (UARTq Receive Data Register).
 UARTq sends... TXDq (UARTq Transmit Data Register).
 IICr Communications... SIOr (IICr Data Register).
Remark m: Unit number (m=0, 1) n: Channel number (n=0~3) p: SSPI number (p=00, 01, 10, 11, 20, 21)
q: UART number (q=0~2) r: IIC number (r=00, 01, 10, 11, 20, 21)