User guide

Arch Meter Corporation PS1000 Ver1.2
PS1000Rev. 1.2 May 2006
41/ 67
www.archmeter.com
S Slave Address PA/~AAAR Data Data
"0" = Write
"1" = Read
Data Transfer
(n Bytes + Acknowledge)
A = Acknowledge (SDA low)
~A = Not Acknowledge (SDA high)
S = START Condition
P = STOP Condition
From Master to Slave
From Slave to Master
Format of master receiver mode
After a repeated START condition, I
2
C may switch to the Master Transmitter
Mode.
S SLA PAAR Data
"0" = Write
"1" = Read
Data Transfer
(n Bytes + Acknowledge)
A = Acknowledge (SDA low)
~A = Not Acknowledge (SDA high)
S = START Condition
P = STOP Condition
SLA = Slave Address
RS = Repeated START Condition
From Master to Slave
From Slave to Master
Data A RS SLA W A Data A
A master receiver switches to master transmitter after sending restart
9.2.3 Slave Receiver Mode
In the Slave Receiver Mode, data bytes are received from a master transmitter.
To initialize the Slave Receiver Mode, the user should write the slave address to
the Slave Address Register (I2CADRR) and the I
2
C Control Register (I2CCTLR)
should be configured as follows:
7 6 5 4 3 2 1 0
I
2
CEN STA STO SI AA - - -
I
2
CCTLR
1 0 0 0 1 - - -
I2CEN must be set to 1 to enable I
2
C function. AA bit must be set to 1 to
acknowledge its own slave address. STA, STO and SI are cleared to 0.
After I2CADRR and I2CCTLR are initialized, the interface waits until it is
addressed by its own address followed by the data direction bit which is 0 (W). If