incubator-nuttx/include/nuttx/leds/max7219.h

124 lines
4.9 KiB
C

/****************************************************************************
* include/nuttx/leds/max7219.h
*
* Copyright (C) 2018 Alan Carvalho de Assis. All rights reserved.
* Author: Alan Carvalho de Assis <acassis@gmail.com>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_LEDS_MAX7219_H
#define __INCLUDE_NUTTX_LEDS_MAX7219_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/fs/ioctl.h>
/* Configuration
* CONFIG_SPI - Enables support for SPI drivers
* CONFIG_LEDS_MAX7219 - Enables support for the MAX7219 driver
*/
#if defined(CONFIG_SPI) && defined(CONFIG_LEDS_MAX7219)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* MAX7219 register addresses */
#define MAX7219_NOOP (0x00) /* No Operation */
#define MAX7219_DIGIT0 (0x01) /* Digit 0 register */
#define MAX7219_DIGIT1 (0x02) /* Digit 1 register */
#define MAX7219_DIGIT2 (0x03) /* Digit 2 register */
#define MAX7219_DIGIT3 (0x04) /* Digit 3 register */
#define MAX7219_DIGIT4 (0x05) /* Digit 4 register */
#define MAX7219_DIGIT5 (0x06) /* Digit 5 register */
#define MAX7219_DIGIT6 (0x07) /* Digit 6 register */
#define MAX7219_DIGIT7 (0x08) /* Digit 7 register */
#define MAX7219_DECODE_MODE (0x09) /* Decode Moder register */
#define MAX7219_INTENSITY (0x0a) /* Intensity register */
#define MAX7219_SCAN_LIMIT (0x0b) /* Scan Limit register */
#define MAX7219_SHUTDOWN (0x0c) /* Shutdown register */
#define MAX7219_DISPLAY_TEST (0x0f) /* Display Test register */
/* Default register values */
#define ENABLE_DECODE (0xff) /* Enable decoding of all 7-seg */
#define DISABLE_DECODE (0x00) /* Disable 7-seg decode */
#define DEFAULT_SCAN_LIMIT (0x07) /* Display all digits */
#define DISPLAY_INTENSITY(n) (n & 0xf) /* low nimble defines it */
/* Only two power settings are supported: */
#define MAX7219_POWER_OFF 0
#define MAX7219_POWER_ON 1
/****************************************************************************
* Public Types
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Name: max7219_leds_register
*
* Description:
* Initialize the MAX7219 device as a LEDS interface.
*
* Input Parameters:
* spi - An instance of the SPI interface to use to communicate
* with the MAX7219.
* devno - Device number to identify current display.
*
* Returned Value:
* Zero (OK) on success; a negated errno value on failure.
*
****************************************************************************/
struct spi_dev_s; /* Forward reference */
int max7219_leds_register(FAR const char *devpath, FAR struct spi_dev_s *spi);
#undef EXTERN
#ifdef __cplusplus
}
#endif
#endif /* CONFIG_SPI && CONFIG_MAX7219 */
#endif /* __INCLUDE_NUTTX_LEDS_MAX7219_H */