SN8P275X Series
8-bit micro-controller build-in 12-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 119
Version 0.7
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MAIN SERIAL PORT (MSP)
10.1 OVERVIEW
The MSP (Main Serial Port) is a serial communication interface for data exchanging from one MCU to one MCU or
other hardware peripherals. These peripheral devices may be serial EEPROM, A/D converters, Display device, etc.
The MSP module can operate in one of two modes
z
Master Tx,Rx Mode
z
Slave Tx,Rx mode (with general address call)
z
Support Single mast,
mutiplex slave.
The MSP features include the following:
z
2-wire synchronous data transfer / receiver.
z
Master (SCL is clock output) or Slave (SC is clock input) operation.
z
SCL, SDA are programmable open-drain output pin for multiple salve devices application.
z
Support 400K clock rate @ Fcpu=4MIPs.
z
End-of-Transfer/Reciver interrupt.
Note. Use ICE emulation MSP function, reference Ch15.1.1
10.2 MSP STATUS REGISTER
MSPSTAT initial value = X000 00X0
090H
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
MSPSTAT
- CKE
D_A P S
RED_WRT
- BF
Read/Write
- R/W
R R R R - R
After
reset
- 0 0 0 0 0 - 0
Bit 6
CKE:
Slave Clock Edge Control bit
In Slave Mode: Receive Address or Data byte
0= Latch Data on SCL Rising Edge. (Default)
1= Latch Data on SCL Falling Edge.
Note 1. In Slave Transmit mode, Address Received depended on CKE setting. Data Transfer on SCL
Falling Edge.
Note 2. In Slave Receiver mode, Address and Data Received depended on CKE setting.
Bit 5
D_A_:
Data/Address_ bit
0=Indicates the last byte received or transmitted was address.
1= Indicates the last byte received or transmitted was data.
Bit 4
P:
Stop bit
0 = Stop bit was not detected.
1 = Indicates that a stop bit has been detected last.
Note1. It will be cleared when Start bit was detected.
Bit 3
S:
Start bit.
0 = Start bit was not detected.
1 = Indicates that a start bit has been detected last
Note1. It will be cleared when STOP bit was detected.
Bit 2
RED_WRT:
Read/Write bit information.