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+CONTENT:
+
+ i2c.h
+ i2c1.c
+ i2c2.s
+
+WHAT ARE THESE FILES:
+
+These files contain MPC8240 (Kahlua) I2C
+driver routines. The driver routines are not
+written for any specific operating system.
+They serves the purpose of code sample, and
+jump-start for using the MPC8240 I2C unit.
+
+For the reason of correctness of C language
+syntax, these files are compiled by Metaware
+C compiler and assembler.
+
+ENDIAN NOTATION:
+
+The algorithm is designed for big-endian mode,
+software is responsible for byte swapping.
+
+USAGE:
+
+1. The host system that is running on MPC8240
+ shall link the files listed here. The memory
+ location of driver routines shall take into
+ account of that driver routines need to run
+ in supervisor mode and they process I2C
+ interrupt.
+
+2. The host system is responsible for configuring
+ the MPC8240 including Embedded Utilities Memory
+ Block. All I2C driver functions require the
+ content of Embedded Utilities Memory Block
+ Base Address Register, EUMBBAR, as the first
+ parameter.
+
+3. Before I2C unit of MPC8240 can be used,
+ initialize I2C unit by calling I2C_Init
+ with the corresponding parameters.
+
+ Note that the I2CFDR register shall be written
+ once during the initialization. If it is written
+ in the midst of transers, or after I2C STOPs or
+ REPEAT STATRs, depending on the data written,
+ a long reset time may be encountered.
+
+4. After I2C unit has been successfully initialized,
+ use the Application level API to send data or
+ receive data upon the desired mode, Master or
+ Slave.
+
+5. If the host system is also using the EPIC unit
+ on MPC8240, the system can register the
+ I2C_ISR with the EPIC including other
+ desired resources.
+
+ If the host system does not using the EPIC unit
+ on MPC8240, I2C_Timer_Event function can
+ be called for each desired time interval.
+
+ In both cases, the host system is free to provide
+ its own timer event handler and interrupt service
+ routine.
+
+6. The I2C driver routines contains a set
+ of utilities, Set and Get, for host system
+ to query and modify the desired I2C registers.
+
+7. It is the host system's responsibility of
+ queueing the I2C I/O request. The host
+ system shall check the I2C_ISR return code
+ for I2C I/O status. If I2C_ISR returns
+ I2CBUFFEMPTY or I2CBUFFFULL, it means
+ I2C unit has completed a I/O request
+ stated by the Application API.
+
+8. If the host system has more than one master
+ mode I2C unit I/O requests but doesn't want
+ to be intervented by being addressed as slave,
+ the host system can use the master mode
+ Application API with stop_flag set to 0 in
+ conjunction with is_cnt flag set to 1.
+ The first API call sets both stop_flag and
+ is_cnt to 0, indicating a START condition
+ shall be generated but when the end of
+ transaction is reached, do not generate a
+ STOP condition. Once the host system is
+ informed that the transaction has been
+ completed, the next Application API call
+ shall set is_cnt flag to 1, indicating a
+ repeated START condition shall be generated.
+ The last Application API call shall set
+ stop_flag
+ to 1.
+
+9. The I2C_Timer_Event function containes
+ a user defined function pointer. It
+ serves the purpose of providing the
+ host system a way to use its own event
+ handler instead of the I2C_ISR provided
+ here.
+
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