neorv32_twi.h

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// ================================================================================ //
// The NEORV32 RISC-V Processor - https://github.com/stnolting/neorv32              //
// Copyright (c) NEORV32 contributors.                                              //
// Copyright (c) 2020 - 2024 Stephan Nolting. All rights reserved.                  //
// Licensed under the BSD-3-Clause license, see LICENSE for details.                //
// SPDX-License-Identifier: BSD-3-Clause                                            //
// ================================================================================ //
 
#ifndef neorv32_twi_h
#define neorv32_twi_h
 
#include <stdint.h>
 
 
/**********************************************************************/
typedef volatile struct __attribute__((packed,aligned(4))) {
  uint32_t CTRL;  
  uint32_t DCMD;  
} neorv32_twi_t;
 
#define NEORV32_TWI ((neorv32_twi_t*) (NEORV32_TWI_BASE))
 
enum NEORV32_TWI_CTRL_enum {
  TWI_CTRL_EN       =  0, 
  TWI_CTRL_PRSC0    =  1, 
  TWI_CTRL_PRSC1    =  2, 
  TWI_CTRL_PRSC2    =  3, 
  TWI_CTRL_CDIV0    =  4, 
  TWI_CTRL_CDIV1    =  5, 
  TWI_CTRL_CDIV2    =  6, 
  TWI_CTRL_CDIV3    =  7, 
  TWI_CTRL_CLKSTR   =  8, 
  TWI_CTRL_FIFO_LSB = 15, 
  TWI_CTRL_FIFO_MSB = 18, 
  TWI_CTRL_TX_FULL  = 29, 
  TWI_CTRL_RX_AVAIL = 30, 
  TWI_CTRL_BUSY     = 31  
};
 
enum NEORV32_TWI_DCMD_enum {
  TWI_DCMD_LSB    =  0, 
  TWI_DCMD_MSB    =  7, 
  TWI_DCMD_ACK    =  8, 
  TWI_DCMD_CMD_LO =  9, 
  TWI_DCMD_CMD_HI = 10  
};
/**********************************************************************/
#define TWI_CMD_NOP   (0b00) // no operation
#define TWI_CMD_START (0b01) // generate start condition
#define TWI_CMD_STOP  (0b10) // generate stop condition
#define TWI_CMD_RTX   (0b11) // transmit+receive data byte
/**********************************************************************/
int  neorv32_twi_available(void);
void neorv32_twi_setup(int prsc, int cdiv, int clkstr);
int  neorv32_twi_get_fifo_depth(void);
void neorv32_twi_disable(void);
void neorv32_twi_enable(void);
 
int  neorv32_twi_busy(void);
int  neorv32_twi_get(uint8_t *data);
 
int  neorv32_twi_trans(uint8_t *data, int mack);
void neorv32_twi_generate_stop(void);
void neorv32_twi_generate_start(void);
 
void neorv32_twi_send_nonblocking(uint8_t data, int mack);
void neorv32_twi_generate_stop_nonblocking(void);
void neorv32_twi_generate_start_nonblocking(void);
#endif // neorv32_twi_h