CCS C Compiler Manual PCB / PCM / PCH

PreProcessor
SLOW
RESTART_WDT
FORCE_HW
FORCE_SW
NOFLOAT_HIGH
SMBUS
STREAM=id
NO_STRETCH
MASK=nn
I2C1
I2C2
NOINIT
Use the slow I2C specification
Restart the WDT while waiting in I2C_READ
Use hardware I2C functions.
Use software I2C functions.
Does not allow signals to float high, signals are
driven from low to high
Bus used is not I2C bus, but very similar
Associates a stream identifier with this I2C port.
The identifier may then be used in functions like
i2c_read or i2c_write.
Do not allow clock streaching
Set an address mask for parts that support it
Instead of SCL= and SDA= this sets the pins to
the first module
Instead of SCL= and SDA= this sets the pins to
the second module
No initialization of the I2C peripheral is performed.
Use I2C_INIT() to initialize peripheral at run time.
Only some chips allow the following:
DATA_HOLD No ACK is sent until I2C_READ is called for data bytes (slave
only)
ADDRESS_HOLD No ACK is sent until I2C_read is called for the address byte
(slave only)
SDA_HOLD Min of 300ns holdtime on SDA a from SCL goes low
Purpose:
CCS offers support for the hardware-based I2C TM and a software-based master I2C TM
device.(For more information on the hardware-based I2C module, please consult the
datasheet for your target device; not all PICs support I2C TM .
The I2C library contains functions to implement an I2C bus. The #USE I2C remains in
effect for the I2C_START, I2C_STOP, I2C_READ, I2C_WRITE and I2C_POLL functions
until another USE I2C is encountered. Software functions are generated unless the
FORCE_HW is specified. The SLAVE mode should only be used with the built-in SSP.
The functions created with this directive are exported when using multiple compilation
units. To access the correct function use the stream identifier.
Examples:
#use I2C(master, sda=PIN_B0, scl=PIN_B1)
#use I2C(slave,sda=PIN_C4,scl=PIN_C3
address=0xa0,FORCE_HW)
#use I2C(master, scl=PIN_B0, sda=PIN_B1, fast=450000)
//sets the target speed to 450 KBSP
Example
Files:
Also See:
ex_extee.c with 16c74.h
i2c_poll, i2c_speed, i2c_start, i2c_stop, i2c_slaveaddr, i2c_isr_state,
i2c_write, i2c_read, I2C Overview
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