Library for the MAX7219 LED display driver
Dependents: MAXREFDES99_demo MAXREFDES99_RTC_Display nucleo_spi_max7219_led8x8 max7219 ... more
max7219.h
- Committer:
- j3
- Date:
- 2016-05-12
- Revision:
- 2:9150a0dc77a3
- Parent:
- 1:90a7cf4e7d26
- Child:
- 3:c245060379b9
File content as of revision 2:9150a0dc77a3:
/******************************************************************//** * @file max7219.h * Copyright (C) 2016 Maxim Integrated Products, Inc., All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. * * Except as contained in this notice, the name of Maxim Integrated * Products, Inc. shall not be used except as stated in the Maxim Integrated * Products, Inc. Branding Policy. * * The mere transfer of this software does not imply any licenses * of trade secrets, proprietary technology, copyrights, patents, * trademarks, maskwork rights, or any other form of intellectual * property whatsoever. Maxim Integrated Products, Inc. retains all * ownership rights. **********************************************************************/ #ifndef MAX7219_H #define MAX7219_H #include "mbed.h" /** * @brief Structure for device configuration * @code * #include "max7219.h" * * max7219_configuration_t cfg = { * .device_number = 1, * .decode_mode = 0, * .intensity = Max7219::MAX7219_INTENSITY_8, * .scan_limit = Max7219::MAX7219_SCAN_8 * }; * @endcode */ typedef struct { uint8_t device_number; uint8_t decode_mode; uint8_t intensity; uint8_t scan_limit; }max7219_configuration_t; /** * @brief Serially Interfaced, 8-Digit, LED Display Driver * * @details The MAX7219/MAX7221 are compact, serial input/output common-cathode * display drivers that interface microprocessors (µPs) to 7-segment numeric * LED displays of up to 8 digits, bar-graph displays, or 64 individual LEDs. * Included on-chip are a BCD code-B decoder, multiplex scan circuitry, segment * and digit drivers, and an 8x8 static RAM that stores each digit. Only one * external resistor is required to set the segment current for all LEDs. * The MAX7221 is compatible with SPI™, QSPI™, and MICROWIRE™, and has * slew-rate-limited segment drivers to reduce EMI. * * @code * #include "mbed.h" * #include "max7219.h" * * Max7219 max7219(SPI0_MOSI, SPI0_MISO, SPI0_SCK, SPI0_SS); * * int main() * { * max7219_configuration_t cfg = { * .device_number = 1, * .decode_mode = 0, * .intensity = Max7219::MAX7219_INTENSITY_8, * .scan_limit = Max7219::MAX7219_SCAN_8 * }; * * max7219.init_device(cfg); * max7219.enable_device(1); * max7219.set_display_test(); * wait(1); * max7219.clear_display_test(); * * while (1) { * max7219.write_digit(1, Max7219::MAX7219_DIGIT_0, ... * } * } * @endcode */ class Max7219 { public: /** * @brief Digit and Control Registers * @details The 14 addressable digit and control registers. */ typedef enum { MAX7219_NO_OP = 0, MAX7219_DIGIT_0, MAX7219_DIGIT_1, MAX7219_DIGIT_2, MAX7219_DIGIT_3, MAX7219_DIGIT_4, MAX7219_DIGIT_5, MAX7219_DIGIT_6, MAX7219_DIGIT_7, MAX7219_DECODE_MODE, MAX7219_INTENSITY, MAX7219_SCAN_LIMIT, MAX7219_SHUTDOWN, MAX7219_DISPLAY_TEST = 15 }max7219_register_e; /** * @brief Intensity values * @details Digital control of display brightness is provided by an * internal pulse-width modulator, which is controlled by * the lower nibble of the intensity register. */ typedef enum { MAX7219_INTENSITY_0 = 0, MAX7219_INTENSITY_1, MAX7219_INTENSITY_2, MAX7219_INTENSITY_3, MAX7219_INTENSITY_4, MAX7219_INTENSITY_5, MAX7219_INTENSITY_6, MAX7219_INTENSITY_7, MAX7219_INTENSITY_8, MAX7219_INTENSITY_9, MAX7219_INTENSITY_A, MAX7219_INTENSITY_B, MAX7219_INTENSITY_C, MAX7219_INTENSITY_D, MAX7219_INTENSITY_E, MAX7219_INTENSITY_F }max7219_intensity_e; /** * @brief Scan limit for mutiplexing digits * @details The scan-limit register sets how many digits are * displayed, from 1 to 8. They are displayed in a multiplexed * manner with a typical display scan rate of 800Hz with 8 * digits displayed. */ typedef enum { MAX7219_SCAN_1 = 0, MAX7219_SCAN_2, MAX7219_SCAN_3, MAX7219_SCAN_4, MAX7219_SCAN_5, MAX7219_SCAN_6, MAX7219_SCAN_7, MAX7219_SCAN_8 }max7219_scan_limit_e; /**********************************************************//** * @brief Constructor for Max7219 Class. * * @details Allows user to pass pointer to existing SPI bus * * On Entry: * @param[in] spi_bus - pointer to existing SPI object * @param[in] cs - pin to use for cs * * On Exit: * @return none **************************************************************/ Max7219(SPI *spi_bus, PinName cs); /**********************************************************//** * @brief Constructor for Max7219 Class. * * @details Allows user to specify SPI peripheral to use * * On Entry: * @param[in] mosi - pin to use for mosi * @param[in] miso - pin to use for miso * @param[in] sclk - pin to use for sclk * @param[in] cs - pin to use for cs * * On Exit: * @return none **************************************************************/ Max7219(PinName mosi, PinName miso, PinName sclk, PinName cs); /**********************************************************//** * @brief Default destructor for Max7219 Class. * * @details Destroys SPI object if owner * * On Entry: * * On Exit: * @return none **************************************************************/ ~Max7219(); /**********************************************************//** * @brief Sets the number of MAX7219 devices being used. * Defaults to one * * @details * * On Entry: * @param[in] num_devices - number of MAX7219 devices being * used, max of 255 * * On Exit: * @return returns number of devices **************************************************************/ int32_t set_num_devices(uint8_t num_devices); /**********************************************************//** * @brief Tests all devices being used * * @details Sets bit0 of DISPLAY_TEST regiser in all devices * * On Entry: * * On Exit: * @return none **************************************************************/ void set_display_test(void); /**********************************************************//** * @brief Stops test * * @details Clear bit0 of DISPLAY_TEST regiser in all devices * * On Entry: * * On Exit: * @return none **************************************************************/ void clear_display_test(void); /**********************************************************//** * @brief initializes specific device in display with given * config data * * @details * * On Entry: * @param[in] config - Structure containing configuration * data of device * * On Exit: * @return returns 0 on success * returns -1 if device number is > _num_devices * returns -2 if device number is 0 **************************************************************/ int32_t init_device(max7219_configuration_t config); /**********************************************************//** * @brief initializes all devices with given config data * * @details all devices are configured with given data * * On Entry: * @param[in] config - Structure containing configuration * data * On Exit: * @return none **************************************************************/ void init_display(max7219_configuration_t config); /**********************************************************//** * @brief enables specific device in display * * @details * * On Entry: * @param[in] device_number - device to enable * * On Exit: * @return returns 0 on success * returns -1 if device number is > _num_devices * returns -2 if device number is 0 **************************************************************/ int32_t enable_device(uint8_t device_number); /**********************************************************//** * @brief enables all device in display * * @details * * On Entry: * * On Exit: * @return none **************************************************************/ void enable_display(void); /**********************************************************//** * @brief disables specific device in display * * @details * * On Entry: * @param[in] device_number - device to disable * * On Exit: * @return returns 0 on success, * returns -1 if device number is > _num_devices * returns -2 if device number is 0 **************************************************************/ int32_t disable_device(uint8_t device_number); /**********************************************************//** * @brief disables all devices in display * * @details * * On Entry: * * On Exit: * @return none **************************************************************/ void disable_display(void); /**********************************************************//** * @brief writes digit of given device with given data, user * must enter correct data for decode_mode chosen * * @details * * On Entry: * @param[in] device_number - device to write too * @param[in] digit - digit to write * @param[in] data - data to write * * On Exit: * @return returns 0 on success, * returns -1 if device number is > _num_devices * returns -2 if device number is 0 * returns -3 if digit > 8 * returns -4 if digit < 1 **************************************************************/ int32_t write_digit(uint8_t device_number, uint8_t digit, uint8_t data); /**********************************************************//** * @brief clears digit of given device * * @details * * On Entry: * @param[in] device_number - device to write too * @param[in] digit - digit to clear * * On Exit: * @return returns 0 on success, * returns -1 if device number is > _num_devices * returns -2 if device number is 0 * returns -3 if digit > 8 * returns -4 if digit < 1 **************************************************************/ int32_t clear_digit(uint8_t device_number, uint8_t digit); /**********************************************************//** * @brief turns on all segments/digits of given device * * @details * * On Entry: * @param[in] device_number - device to write too * * On Exit: * @return returns 0 on success, * returns -1 if device number is > _num_devices * returns -2 if device number is 0 **************************************************************/ int32_t device_all_on(uint8_t device_number); /**********************************************************//** * @brief turns off all segments/digits of given device * * @details * * On Entry: * @param[in] device_number - device to write too * * On Exit: * @return returns 0 on success, * returns -1 if device number is > _num_devices * returns -2 if device number is 0 **************************************************************/ int32_t device_all_off(uint8_t device_number); /**********************************************************//** * @brief turns on all segments/digits of display * * @details * * On Entry: * * On Exit: * @return none **************************************************************/ void display_all_on(void); /**********************************************************//** * @brief turns off all segments/digits of display * * @details * * On Entry: * * On Exit: * @return none **************************************************************/ void display_all_off(void); private: SPI *_p_spi; DigitalOut *_p_cs; bool _spi_owner; uint8_t _num_devices; }; #endif /* MAX7219_H*/