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ARM_TWI.h
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ARM_TWI.h
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/*
TWD0 PA3 Peripheral A
TWCK0 PA4 Peripheral A
*/
#ifndef ARM_TWI_H
#define ARM_TWI_H
#include "stdint.h"
/*
Settings for TWI speed.
T_high = (CHDIV * 2^CKDIV + 4) * (1 / MCK)
T_low = (CLDIV * 2^CKDIV + 4) * (1 / MCK)
F_twi = 1 / (T_high + T_low)
64MHz MCK
(79 * 2^2 + 4) * (1 / 64000000) = 0.000005
1 / (0.000005 + 0.000005) = 100000kHz
2MHz MCK
(3 * 2^1 + 4) * (1 / 2000000) = 0.000005
1 / (0.000005 + 0.000005) = 100000kHz
*/
#define CHDIV 3 // 0-255
#define CLDIV 3 // 0-255
#define CKDIV 1 // 0-7
#define TWI_TIMEOUT 1000 // shorter timeout during 2MHz PLL operation
static uint8_t nack = 0;
// Functions
void TWI_init_master(void);
void TWI_deinit(void);
void TWI_write(uint8_t addr, uint8_t intaddrlen, uint8_t intaddr16, uint8_t intaddr8, uint8_t intaddr0, uint8_t *data, uint8_t datalen);
uint8_t TWI_read(uint8_t addr, uint8_t intaddrlen, uint8_t intaddr16, uint8_t intaddr8, uint8_t intaddr0, uint8_t *data, uint8_t datalen);
#endif // ARM_TWI_H