Calibre UK ICA93LV user manual Using the Utilities, Routines 1. I2C Setup/Initialisation Routine

5.Using the Utilities

Each utility is documented in a standard format, which lists its name, usage, function, and effect on the adapter is given. Following a reset, the adapter should be setup prior to any data transfer.

5.1.C Routines

5.1.1.I2C Setup/Initialisation Routine

Name:	setup(base, own, sclk)
Usage:	setup(base, own, sclk);
Function:	procedure to set up I2C Communications Adapter.
Parameters are:
int base	base address of adapter set by links on circuit board.
int own	I2C address to which the adapter is to respond in slave mode. This forms the
	upper 7 bits of the 8 bit address; the lowest bit being the Read (1) or Write (0) bit.
	This means that if own = 0x57, the card will respond to a Write to address 0xAE
	and a Read to address 0xAF. Be sure not to select an address that is already in
	use by any other device in your I2C system. If own = 0x00 the adapter will monitor
	all I2C bus information but will not affect any data transfers, thus acting as a bus
	monitor.
int sclk	the SCL clock rate (bit rate for I2C serial bus).
	Value of sclk	Approximate SCL (kHz)
	0	90
	1	45
	2	11
	3	1.5

Value Returned:none.

I2C status on exit from routine:

	The I2C Communications Adapter will have the serial interface enabled; also data
	reception acknowledge will be enabled. The status register will contain 0x81
	(assuming that no other masters exist on the I2C system, if this is not the case
	then the contents of the status register will also depend on externally generated
	bus activity).
Example Usage: (see also sample programs)
#include <stdio.h>
#include <dos.h>	/*Optional, but recommended if your compiler */
	/*supports DOS I/O functions */
#include <i2c.h>	/*This contains the I2C routines */
main

{
int base, own, sclk;
base = 0x310;	/* Adapter’s base address = 0x310 (hex) */
own = 0x57;	/* Own slave address set to 0x57 (hex) */
sclk = 1;	/* Serial clock rate set to 45KHz */
setup(base, own sclk);

printf(“I2C Communications Adapter initialised\n”);

}

/* This will set up the I2C Communications Adapter with a base */ /* address of 0x310, an I2C slave address of 0xAE and a SCL */ /* clock rate of approximately 45KHz */

5.1.2.I2C Status Checking Routine

Name:	getstatus(controladdress)
Usage:	status = getstatus(controladdress);
Function:	function to read status register of I2C Communications Adapter.
Revision 1.7	Page 6 of 27
09/12/1999