Revision 2:7c27fb9785be, committed 2013-01-29

Comitter:

Yann

Date:

Tue Jan 29 15:02:08 2013 +0000

Parent:

1:cf3cee91eb87

Child:

3:0acab5201dd8

Commit message:

Add /CS supported by library

Changed in this revision

--- a/MCP4xxxx_SPI.cpp	Sun Jan 27 17:04:05 2013 +0000
+++ b/MCP4xxxx_SPI.cpp	Tue Jan 29 15:02:08 2013 +0000
@@ -23,7 +23,7 @@
 
     unsigned char CMCP4xxxx_SPI::SPIModuleRefCounter = 0;
 
-    CMCP4xxxx_SPI::CMCP4xxxx_SPI(const PinName p_mosi, const PinName p_miso, const PinName p_sclk, const PinName p_reset, const PinName p_shdn, const unsigned int p_frequency) : _internalId("") {
+    CMCP4xxxx_SPI::CMCP4xxxx_SPI(const PinName p_mosi, const PinName p_miso, const PinName p_sclk, const PinName p_cs, const PinName p_reset, const PinName p_shdn, const unsigned int p_frequency) : _internalId("") {
         DEBUG_ENTER("CMCP4xxxx_SPI")
 
         if (CMCP4xxxx_SPI::SPIModuleRefCounter != 0) {
@@ -36,6 +36,15 @@
         CMCP4xxxx_SPI::SPIModuleRefCounter += 1;
         DEBUG_ENTER("CMCP4xxxx_SPI: refCounter=%d", CMCP4xxxx_SPI::SPIModuleRefCounter)
 
+        if (p_cs != NC) {
+            DEBUG("CMCP4xxxx_SPI: /CS managed");
+            _cs = new DigitalOut(p_cs);
+            _cs->write(1); // Disable chip
+        } else {
+            DEBUG("CMCP4xxxx_SPI: /CS not managed");
+            _cs = NULL; // Not used
+        }
+    
         if (p_reset != NC) {
             DEBUG("CMCP4xxxx_SPI: /RESET managed");
             _reset = new DigitalOut(p_reset);
@@ -68,11 +77,16 @@
             _spiInstance = NULL;
         }
         // Release _reset if required
+        if (_cs != NULL) {
+            _cs->write(0);
+            delete _cs;
+        }
+        // Release _reset if required
         if (_reset != NULL) {
             _reset->write(0);
             delete _reset;
         }
-         // Release _shdn if required
+        // Release _shdn if required
         if (_shdn != NULL) {
             _shdn->write(0);
             delete _shdn;
@@ -103,7 +117,13 @@
         } // End of 'switch' statement
         
         DEBUG("CMCP4xxxx_SPI: Send command: 0x%04x", command)
+        if (_cs != NULL) {
+            _cs->write(0);
+        }
         unsigned short result = _spiInstance->write(command);
+        if (_cs != NULL) {
+            _cs->write(1);
+        }
         
         DEBUG_LEAVE("CMCP4xxxx_SPI::Write: %d", result)
         return result;
@@ -131,7 +151,13 @@
         } // End of 'switch' statement
         
         DEBUG("CMCP4xxxx_SPI: Send command: 0x%04x", command)
+        if (_cs != NULL) {
+            _cs->write(0);
+        }
         unsigned short result = _spiInstance->write(command);
+        if (_cs != NULL) {
+            _cs->write(1);
+        }
         
         DEBUG_LEAVE("CMCP4xxxx_SPI::Write: %d", result)
         return result;
@@ -148,7 +174,7 @@
         
         _reset->write(0); // Set level low to activate reset 
         wait_us(1); // Wait for 1us
-         _reset->write(1); // Set level low to de-activate reset 
+        _reset->write(1); // Set level low to de-activate reset 
        
         return true;
     }

--- a/MCP4xxxx_SPI.h	Sun Jan 27 17:04:05 2013 +0000
+++ b/MCP4xxxx_SPI.h	Tue Jan 29 15:02:08 2013 +0000
@@ -41,12 +41,18 @@
          */
         static unsigned char SPIModuleRefCounter;
         
-        /** Reset state indicator (pin 11); true to reset device, false otherwise (DS11195C-page 21 Clause 5.5 Reset (RS) Pin Operation)
+        /** ChipSelect (pin 1) see DS11195C-page 12 Clause 3.4 Chip Select (CS)
+         */
+        DigitalOut *_cs;
+        
+        /** Reset state indicator (pin 11), see DS11195C-page 21 Clause 5.5 Reset (RS) Pin Operation
          */
         DigitalOut *_reset;
-        /** Shutdown state indicator (pin 12); true to shutdown device, false otherwise (DS11195C-page 21 5.6 Shutdown (SHDN) Pin Operation)
+        
+        /** Shutdown state indicator (pin 12) see DS11195C-page 21 5.6 Shutdown (SHDN) Pin Operation
          */
         DigitalOut *_shdn;
+        
         /** An unique instance of SPI class
          */
         SPI *_spiInstance;
@@ -68,11 +74,12 @@
          * @param p_mosi: MBed pin for SDI
          * @param p_miso: MBed pin for SDO. Note that this pin does not exist for MCP41xxx
          * @param p_sclk: MBed pin for CLK
+         * @param p_cs  : MBed pin for Chip Select. If NC, assumes that application manage /CS, default value is NC, not connected
          * @param p_reset: MBed pin to manage /RESET input. If NC, /RESET is not managed, default value is NC, not connected
          * @param p_shdn: MBed pin to manage /SHDN input. If NC, /SHDN is not managed, default value is NC, not connected
          * @param p_frequency: Frequency of the SPI interface (SCK), default value is 1MHz
          */
-        CMCP4xxxx_SPI(const PinName p_mosi, const PinName p_miso, const PinName p_sclk, const PinName p_reset = NC, const PinName p_shdn = NC, const unsigned int p_frequency = 1000000);
+        CMCP4xxxx_SPI(const PinName p_mosi, const PinName p_miso, const PinName p_sclk, const PinName p_cs = NC, const PinName p_reset = NC, const PinName p_shdn = NC, const unsigned int p_frequency = 1000000);
     
         /** Destructor
          */
@@ -86,7 +93,7 @@
          *
          * @param p_command The command to execute: Write or Shutdown (See DS11195C-page 18)
          * @param p_value The potentiometer selection bits (See DS11195C-page 14 Clause 4.1 Modes of Operation)
-         * @return 0x00 on success, 0Xffff otherwise
+         * @return 0x0000 on success, 0Xffff otherwise
          * Exemple:
          * @code
          * unsigned char potLevel;
@@ -103,7 +110,7 @@
          *
          * @param p_command The command to execute: Write or Shutdown (See DS11195C-page 18)
          * @param p_value The potentiometer selection bits (See DS11195C-page 14 Clause 4.1 Modes of Operation)
-         * @return 0x00 on success, 0Xffff otherwise
+         * @return 0x0000 on success, 0Xffff otherwise
          * Exemple:
          * @code
          * ...