DSPIC30F3011 Microchip Technology Inc., DSPIC30F3011 Datasheet - Page 113

• Manufacturer Part Number: DSPIC30F3011
• Description: Dspic30f3010/3011 Enhanced Flash 16-bit Digital Signal Controller
• Manufacturer: Microchip Technology Inc.

17.7
The I
(I
Interrupt Flag). The MI2CIF interrupt flag is activated
on completion of a master message event. The SI2CIF
interrupt flag is activated on detection of a message
directed to the slave.
17.8
The I
and SCL signals for Fast Mode (400 kHz). The control
bit, DISSLW, enables the user to disable slew rate
control, if desired. It is necessary to disable the slew
rate control for 1 MHz mode.
17.9
The control bit IPMIEN enables the module to support
Intelligent Peripheral Management Interface (IPMI).
When this bit is set, the module accepts and acts upon
all addresses.
17.10 General Call Address Support
The general call address can address all devices.
When this address is used, all devices should, in
theory, respond with an acknowledgement.
The general call address is one of eight addresses
reserved for specific purposes by the I
consists of all 0’s with R_W = 0.
The general call address is recognized when the Gen-
eral Call Enable (GCEN) bit is set (I2CCON<7> = 1).
Following a start bit detection, 8 bits are shifted into
I2CRSR and the address is compared with I2CADD,
and is also compared with the general call address
which is fixed in hardware.
If a general call address match occurs, the I2CRSR is
transferred to the I2CRCV after the eighth clock, the
RBF flag is set, and on the falling edge of the ninth bit
(ACK bit), the master event interrupt flag (MI2CIF) is
set.
When the interrupt is serviced, the source for the
interrupt can be checked by reading the contents of the
I2CRCV to determine if the address was device
specific, or a general call address.
© 2007 Microchip Technology Inc.
2
C Master Interrupt Flag) and SI2CIF (I
2
2
C module generates two interrupt flags, MI2CIF
C standard requires slope control on the SDA
Interrupts
Slope Control
IPMI Support
2
C protocol. It
2
C Slave
Confidential
17.11 I
As a Master device, six operations are supported:
• Assert a Start condition on SDA and SCL
• Assert a Restart condition on SDA and SCL
• Write to the I2CTRN register initiating
• Generate a Stop condition on SDA and SCL
• Configure the I
• Generate an ACK condition at the end of a
17.12 I
The master device generates all of the serial clock
pulses and the Start and Stop conditions. A transfer is
ended with a Stop condition or with a Repeated Start
condition. Since the Repeated Start condition is also
the beginning of the next serial transfer, the I
not be released.
In Master Transmitter mode, serial data is output
through SDA, while SCL outputs the serial clock. The
first byte transmitted contains the slave address of the
receiving device (7 bits) and the data direction bit. In
this case, the data direction bit (R_W) is logic ‘0’. Serial
data is transmitted 8 bits at a time. After each byte is
transmitted, an ACK bit is received. Start and Stop
conditions are output to indicate the beginning and the
end of a serial transfer.
In Master Receive mode, the first byte transmitted
contains the slave address of the transmitting device
(7 bits) and the data direction bit. In this case, the data
direction bit (R_W) is logic ‘1’. Thus, the first byte
transmitted is a 7-bit slave address, followed by a ‘1’ to
indicate receive bit. Serial data is received via SDA,
while SCL outputs the serial clock. Serial data is
received 8 bits at a time. After each byte is received,
an ACK bit is transmitted. Start and Stop conditions
indicate the beginning and end of transmission.
17.12.1
Transmission of a data byte, a 7-bit address or the
second half of a 10-bit address is accomplished by
simply writing a value to I2CTRN register. The user
should only write to I2CTRN when the module is in a
WAIT state. This action will set the buffer full flag (TBF)
and allow the Baud Rate Generator to begin counting
and start the next transmission. Each bit of address/
data will be shifted out onto the SDA pin after the falling
edge of SCL is asserted. The Transmit Status Flag,
TRSTAT (I2CSTAT<14>), indicates that a master
transmit is in progress.
transmission of data/address
received byte of data
dsPIC30F3010/3011
2
2
C Master Support
C Master Operation
I
2
C MASTER TRANSMISSION
2
C port to receive data
DS70141D-page 111
2
C bus will