Calibre UK PICA93LV user manual Int ErrCode, Int wrData

CALIBRE

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	This is a period of time (in micro seconds) to wait for the required bus status.
	If this time-out expires the I2C functions will exit returning an error code.
	int sclk
	This is the clock rate (bit rate for the I2C serial bus) when operating as a
	master.
	Value of sclk	Approximate SCL-KHz
	0	90
	1	45
	2	11
	3	1.5
Parameters returned	None.
Prerequisites	None.
Functional description	This function	characterises the PC and initialise adapter ready for I2C
	transfers.

4.4.5.sendaddress

Function specification		Int sendaddress(int slaveaddress, int setnack)
Parameters are:		int slaveaddress
		This is the address to be accessed via the I2C, e.g. A0H.
		int setnack
		This controls whether the Parallel I2C Communications Adapter transmits an
		Acknowledge down the I2C Bus on reception of a byte. The last byte received
		during a transfer must not be acknowledged, in all other cases acknowledge
		must be enabled. If setnack = 0 then acknowledge is enabled, if setnack = 1
		then acknowledge is disabled. Therefore, if a read (odd numbered) address is
		being sent AND only 1 Byte is to be read, setnack should be set to = 1; in all
		other cases it must be clear = 0.
Parameters returned		int ErrCode.
		If the transfer time out occurs error code 8001H is returned otherwise the
		status is returned.
Prerequisites		The adapter must be configured for PC and application by running setup.
Functional description		The function waits for the bus to be free. Then sends the slave address with
		the appropriate acknowledge.
		The acknowledge is set ready for the data transfer after the address and
		hence in read mode (odd address being sent) if only one byte is to be read
		the setnack parameter must equal 1. If more than one byte is to be read or if
		in write mode (even address being sent) then setnack must equal 0.
		The function waits for the address to be sent. Should a time-out occur during
		the sending of an address then an error code 8001H is returned, otherwise
		the status is returned.
4.4.6.	writebyte
Function specification		Int writebyte(int wrData)
Parameters are:		int wrData
		This is the byte of data to be written.
Issue 1.3		Page 21

22/07/99