Diff: Max7221.h

Revision:

7:a160cb7cdd86

Parent:

6:191569a26f50

Child:

8:3f5901f2f813

--- a/Max7221.h	Thu Nov 19 23:58:07 2015 +0000
+++ b/Max7221.h	Mon Nov 23 11:28:44 2015 +0000
@@ -1,179 +1,108 @@
 /**
 * @file Max7221.h
-* @brief This file contains the class defnition of Max7221 and define statements related to the class, and max7221 device
-* The methods in this class are derived from posts on the mbed forum written by Igor Skochinsky on October 2009
+* @brief Header file for the MAX7219/7221 driver class.
 * 
-* @author Dwayne S. Dilbeck
-*
-* @date 8/6/2013
+* @author Grzegorz Kaczmarek
+* @comment Code inspired on erlier Dwayne S. Dilbeck's work
+* @date 20/11/2015
 */
+
 #ifndef Max7221_H
 #define Max7221_H
 
-
-// define max7219/max7221 registers
+// MAX7219/7221 register map
 #define max7219_reg_noop         0x00
-#define max7219_reg_digit0       0x01
-#define max7219_reg_digit1       0x02
-#define max7219_reg_digit2       0x03
-#define max7219_reg_digit3       0x04
-#define max7219_reg_digit4       0x05
-#define max7219_reg_digit5       0x06
-#define max7219_reg_digit6       0x07
-#define max7219_reg_digit7       0x08
 #define max7219_reg_decodeMode   0x09
 #define max7219_reg_intensity    0x0a
 #define max7219_reg_scanLimit    0x0b
 #define max7219_reg_shutdown     0x0c
 #define max7219_reg_displayTest  0x0f
 
-#define LOW 0
-#define HIGH 1
-#define MHZ 1000000
-#define NUMDIGITS 8
-
-#ifdef NUMDIGITS 
-#define UPPERBOUND 99999999
-#define LOWERBOUND -9999999
-#endif
+// Logical values
+#define LOG_0 0
+#define LOG_1 1
 
-/**
- * Max7221 Example
- * @code
- * #include "mbed.h"
- * #include "Max7221.h"
- *  
- * 
- * // p5: DIN, p7: CLK, p8: LOAD/CS
- * Max7221 max7221disp1(p5, p7, p8);
- * //Max7221 max7221disp2(p5, p7, p8);
- * //Max7221 max7221disp3(p11, p13, p14);
- * //Max7221 max7221disp4(p11, p13, p14);
- * 
- * int count=-99;
- * 
- * void loop(void) {
- *    max7221disp1.WriteInt(count);
- *    if (count < 100)
- *       count=count+1;
- *    else 
- *      count=-99; 
- * }
- * 
- * int main() {  
- *     max7221disp1.Setup();
- *     //Max7221::SetupALl();
- *     max7221disp1.WriteFloat(123.125);
- *     wait(1.0);  
- * 
- *     while (1) {
- *         loop(); 
- *         wait(1.0);
- *     }
- * }
- * @endcode
- */
 class Max7221 {
+private:
+   SPI *mp_spi;             // SPI used for this display (no data transmission when NULL)
+   DigitalOut *mp_cs;       // CS signal (it should be handled manually when NULL)
+   unsigned int m_position; // Display position on SPI chain (0 = 1'st)
+
 public:
     /**
-    *  Constructor. This is the default constructor
-    *  @author Dwayne S. Dilbeck
-    *  @param msoi  The SPI pin used as input to the device.       Valid values for LPC1768 are p5 or p11
-    *  @param mclk  The SPI pin used as clock for the device.      Valid values for LPC1768 are p7 or p13
-    *  @param load  The pin used to control load for the device.   Any pin capable for DigitalOut can be used, but the same load pin must be used for 
-    *    device that share the same msoi and mclk pins
-    *  @date 8/6/2013
+    *  Default constructor.
+    *  @param spi       Initialized SPI port used for communication with MAX7219/7221.
+    *  @param cs        Initialized output pin used as SW CS signal or NULL when HW one is used.
+    *  @param position  Position on SPI port (for displays connected in daisy-chain: DOUT-DIN). 0=1st.
+    */
+    Max7221(SPI *spi, DigitalOut *cs, unsigned int position=0);
+
+    /**
+    *  Method for setting /CS signal LOW (enable data reception).
     */
-    Max7221(PinName msoi=PTC6, PinName mclk=PTC5, PinName load=PTC4);
+    void CsLow(void);
+
+    /**
+    *  Method for setting /CS signal HIGH (received data is latched and processed).
+    */
+    void CsHigh(void);
+
+    /**
+    *  Method used to send data over SPI (no use of /CS signal).
+    *  To be used with display chains and when building display libraries
+    *  where amount of data needs to be pushed via SPI in one transaction.
+    */
+    void WriteRaw(unsigned int reg, unsigned int data);
    
     /**
-    *  This method is used to write a byte of data to a specified register for only the device defined in this class instance
-    *  @author Dwayne S. Dilbeck
-    *  @param reg  The register to write to.
-    *  @param data The value to be written.
-    *  @date 8/6/2013   
+    *  Method for sending register-value pair for this diasplay.
+    *  Supports display chain on single SPI (m_position > 0).
     */
-    void Write( unsigned int reg, unsigned int data);
+    void Write(unsigned int reg, unsigned int data);
 
     /**
-    *  This method is used to display an integer to the specified device instance. Underflow and overflow result in '-' written to all digits
-    *  @author Dwayne S. Dilbeck
-    *  @param value  An integer value to display
-    *  @date 8/6/2013   
-    */   
-    void WriteInt( int value );
+    *  Sets test mode which causes all display LEDs to emit light with full brightess.
+    *  @param mode  true - test mode, false - normal operation.
+    */
+    void TestMode(bool mode);
+    
+    /**
+    *  Sets amount of digits to be used by this display.
+    *  @param digits_no  1 - one digit, (2-7), 8 - all 8 digits.
+    */
+    void UseDigitsNo(unsigned int digits_no);
 
     /**
-    *  This method is used to display a floating point number to the specified device instance. 
-    *   Underflow and overflow result in '-' written to all digits. The digits after the decimal 
-    *   point are truncated to fit the display.
-    *  @author Dwayne S. Dilbeck
-    *  @param value  A float value to display
-    *  @date 8/6/2013   
-    */   
-    void WriteFloat( float value);
-   
-    /**
-    *  Overload of the EQUALS operator to provide easy use of the class.
-    *  @author Dwayne S. Dilbeck
-    *  @param value  An integer value to display
-    *  @date 8/6/2013   
-    */      
-    Max7221& operator= (int value){ 
-        WriteInt(value); 
-        return *this;
-        };
-    /**
-    *  Overload of the EQUALS operator to provide easy use of the class.
-    *  @author Dwayne S. Dilbeck
-    *  @param value  A float value to display
-    *  @date 8/6/2013   
-    */   
-    Max7221& operator= (float value){ 
-        WriteFloat(value); 
-        return *this; 
-        };
+    *  Selects for which digits Code-B data decoding is used.
+    *  @param mode  0x00 - no decoding, 0x0F - digits 0-3, 0xFF - all digits.
+    */
+    void DecodeMode(unsigned int mode);
 
     /**
-    *  This method is used to write an  intial set off values to the device to prepare it for use.
-    *  @author Dwayne S. Dilbeck
-    *  @date 8/6/2013   
-    */   
-    void Setup (void);
-
-    /**
-    *  This method is used to write a byte of data to a specified register for all the devices instantiated.
-    *  @author Dwayne S. Dilbeck
-    *  @param reg  The register to write to.
-    *  @param data The value to be written.
-    *  @date 8/6/2013   
-    */   
-    static void WriteAll (unsigned int reg, unsigned int data);
+    *  Sends data to selected digit.
+    *  @param digit_no  Selected digit (0-7).
+    *  @param digit_no  Data to display.
+    */
+    void WriteDigit(unsigned int digit_no, unsigned int value);
 
     /**
-    *  This method is used to write an intial set off values to ALL device to prepare them for use.
-    *  @author Dwayne S. Dilbeck
-    *  @date 8/6/2013   
+    *  Sets display brightness.
+    *  @param intensity  0x00 - minimum brightness, 0x0F - maximum brightness.
+    */
+    void Intensity(unsigned int intensity);
+
+    /**
+    *  Sets display operation mode.
+    *  @param mode  true - normal operation, false - shutdown mode.
+    */
+    void OperationMode(bool mode);
+    
+    /**
+    *  Initial setup of this display.
+    *  8-digit blank decimal display set to nimimal brightness.
+    *  Supports display chain on single SPI (m_position > 0).
     */   
-    static void SetupAll (void);
-   
-private:
-   /// Pointer for the class instance to a particular SPI bus
-   SPI *max7221_spi;
-   /// pointer for the class instance of a particular load signal
-   DigitalOut *max7221_cs;
-   ///  id of the class instance
-   int id;
-   /// pointer to the number of devices connected to the SPI bus instance this device instance is connected to.
-   int *maxInUse;
-   
-   ///For the class we have a static set of values.  There are 2 SPI buses, 2 load signals, and 2 counters of the number of devices connected to a SPI bus.
-   static SPI *spi;
-//   static SPI *spi2;
-   static DigitalOut *cs;
-//   static DigitalOut *load2;
-   static int maxInUseSPI;
-//   static int maxInUseSPI2;
+    void Setup(void);
 };
 
 #endif
\ No newline at end of file