Class _swtwimaster: software-emulated TWI (master only)

Detailed Description

This class implements a software-emulated TWI master.

Attention

This class may not be supported by all devices.

Header file:

#include <hwa/ext/swtwimaster.h>

Interface

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HW_SWTWIMASTER( scl, <scl>, sda, <sda>, bps, <bps> ) defines a SWTWIMASTER object:

• <scl>: an I/O for the SCL signal;
• <sds>: an I/O for the SDA signal;
• <bps>: the SCL frequency.

Example:

#define TWI     HW_SWTWIMASTER( scl, (portc,5),
                                sda, (portc,4),
                                bps, 400000 )

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HW_DECLARE( TWI ) declares the functions that implement the TWI object:

HW_DECLARE( TWI );

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HW_IMPLEMENT( TWI ) declares the functions that implement the TWI object:

HW_IMPLEMENT( TWI );

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hw( configure, TWI ) and hwa( configure, TWI ) configure the object:

hw( configure, TWI );

hwa( configure, TWI );

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hw( xfr_start, TWI ) sends a start condition on the TWI bus:

hw( xfr_start, TWI );

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hw( xfr_slar, TWI, slave_address ) sends slave address + read bit:

hw( xfr_slar, TWI, slave_address );

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hw( xfr_slaw, TWI, slave_address ) sends slave address + write bit:

hw( xfr_slaw, TWI, slave_address );

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hw( xfr_read, TWI, data, ack|nack ) receive one data byte:

uint8_t r = hw( xfr_read, TWI, ack );

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hw( xfr_write, TWI, data ) transmit one data byte:

uint8_t r = hw( xfr_write, TWI, data ); // r = ack|nack

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hw( xfr_stop, TWI ) sends a start condition on the TWI bus:

hw( xfr_stop, TWI );

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hw( stat, TWI ) get the status byte of the object:

uint8_t st = hw( stat, TWI );

Macros
#define	HW_SWTWIMASTER(...)