MS6821
MOSA
4 Stereo inputs / 2W PA output integrated Audio DAC and Volume Control
I2C CONTROL INTERFACE
DataꢀareꢀtransmittedꢀtoꢀandꢀfromꢀtheꢀMCUꢀtoꢀtheꢀMS6821ꢀviaꢀtheꢀSDAꢀandꢀSCL.ꢀTheꢀSDAꢀandꢀSCLꢀmakeꢀupꢀtheꢀ
BUSꢀinterface.ꢀItꢀshouldꢀbeꢀnotedꢀthatꢀpullꢂupꢀresistorsꢀmustꢀbeꢀconnectedꢀtoꢀtheꢀpositiveꢀsupplyꢀvoltage.ꢀ
VDD
Rp
Rp
Pullꢀupꢀresistors
SDAꢀ(SerialꢀDataꢀLine)
SCLꢀ(SerialꢀClockꢀLine)
MCU
MS6821
I2C interface protocol
Theꢀformatꢀconsistsꢀofꢀtheꢀfollowing:ꢀ
•AꢀSTARTꢀconditionꢀ
•Aꢀchipꢀaddressꢀbyteꢀincludingꢀtheꢀchipꢀaddress.ꢀ(7bits)ꢀ
•Theꢀ8thꢀbitꢀofꢀtheꢀbyteꢀmustꢀbeꢀ“0”.(write=0,ꢀread=1)ꢀ
•Theꢀchipꢀmustꢀalwaysꢀacknowledgeꢀtheꢀendꢀofꢀeachꢀtransmittedꢀbyte.ꢀ
•Aꢀdataꢀsequenceꢀ(Nꢂbytesꢀ+ꢀAcknowledge)ꢀ
•AꢀSTOPꢀconditionꢀ
ꢀ
SDA
SCL
1ꢁ7
8
9
1ꢁ7
8
9
1ꢁ7
8
9
S
P
STOP
ADDRESS
ACK
DATA
ACK
DATA
ACK
R / W
START
CONDITION ꢀ
CONDITION
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
I2C chip address
88H
1
0
0
0
1
0
0
0
7ꢀbitsꢀaddress
W
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
REVꢀ 1.0
ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ 14ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ ꢀ www.mosanalog.comꢀ
MOSA [ MOSA ELECTRONICS ]
