Squashed commit of the following:

configs/stm32f4discovery/src: Add board support to MAX7219 as numeric display controller drivers/leds/max7219.c: Add support to MAX7219 to control 7-segment displays
2026-06-08 01:42:58 +08:00 · 2018-07-22 15:13:39 -06:00
parent d77df925a3
commit f887bdb6d6
9 changed files with 588 additions and 2 deletions
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+/****************************************************************************
+ * 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 */