Revision 0:22c6b94e7da6, committed 2014-03-13

Comitter:

hexley

Date:

Thu Mar 13 17:52:43 2014 +0000

Commit message:

Initial version

Changed in this revision

diff -r 000000000000 -r 22c6b94e7da6 capturet0_11u24.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/capturet0_11u24.cpp	Thu Mar 13 17:52:43 2014 +0000
@@ -0,0 +1,120 @@
+ /* mbed Library - Capture driver for CT32B0
+ * Copyright (c) 2010
+ * released under MIT license http://mbed.org/licence/mit
+ */
+ /***********************************************************************//**
+ * @file        capturet1_11u24.cpp
+ * @brief       Driver file for the CAP1 function of CT32B0 in the  mbed 11U24. 
+ * @version     0.0
+ * @date        05 Feb 2014
+ * @author      
+ **************************************************************************/
+#include "mbed.h"
+#include "capturet0_11u24.h"
+
+Capture *Capture::instance;
+
+/*********************************************************************//**
+ * @brief       Create a Capture object and configure it. 
+ * @param       None   Uses p7 as the Capture input
+ * @return      None
+ **********************************************************************/
+Capture::Capture(void)
+{       
+    /* Set up clock and power, using default peripheral system clock divider */   
+    LPC_SYSCON->SYSAHBCLKCTRL |=   CT32B0_CLK_ENABLE; // See page 30 of the 11U24 User Guide
+    // Check the clock divider ratio by reading   LPC_SYSCON->SYSAHBCLKDIV ls byte
+    LPC_CT32B0->PR  =  0;                           // Prescale counter divide by 1
+       
+    /* Configure IOCON for the proper function of the capture pin. Use a pull-up.     */
+    LPC_IOCON->PIO1_29 = (CT32B0_CAP1 | CAP_PULLUP); // See page 114 of the 11U24 User Guide   
+              
+    // Select the capture edge and int mode
+    LPC_CT32B0->CCR =   CCR_CAP1FE  | CCR_CAP1I;    // Select inputs and interrupts. See page 345
+    
+    // Set up the rising edge clear, using timer mode
+    LPC_CT32B0->CTCR = CTCR_CTM_TIMER | CTCR_ENCC | CTCR_SEICC_CAP1RE; // See page 350
+    
+        
+    // Clear interrupt flag
+    LPC_CT32B0->IR = IR_CR1INT;     // See page 342             
+  
+    /* preemption = 1, sub-priority = 1 */
+//    NVIC_SetPriority(TIMER2_IRQn, ((0x01<<3)|0x01));
+//     NVIC_SetPriority(TIMER2_IRQn, 0);          // Set to top priority to minimize interference from tickers.
+     
+    //* Attach IRQ
+    instance = this;
+    NVIC_SetVector(TIMER_32_0_IRQn, (uint32_t)&_Captureisr);                   
+  
+}
+
+/*********************************************************************//**
+ * @brief        Start capturing data. Average the specified number of samples. 
+ * @param        (int) numsamples    Log base 2 of the number of samples to be averaged
+ * @return        None
+ **********************************************************************/
+void Capture::Start(int numsamples) {
+    Nsamples = numsamples;
+    capturedata = 0;                        // Clear the accumulator
+    flag = 0;                               // No data ready
+    
+    /* Enable interrupt for CAPTURE  */
+    NVIC_EnableIRQ(TIMER_32_0_IRQn); 
+    
+    // Start the timer
+    LPC_CT32B0->TCR =  TCR_CEN; // enable
+}
+
+/*********************************************************************//**
+ * @brief        Read (accumulated) sample count. 
+ * 
+ * @return       (unsigned int) Accumulated capture value
+ **********************************************************************/
+unsigned int Capture::Read(void) {
+    flag = 0;                   // Clear previous status (or error)
+    return capturedata;
+}
+
+/*********************************************************************//**
+ * @brief        Check for accumulation complete (data is ready to read). 
+ * 
+ * @return       (unsigned int) Accumulated capture value
+ **********************************************************************/
+int Capture::Ready(void) {
+    return flag;
+}
+
+
+/* Capture isr instantiator */    
+void Capture::_Captureisr(void)
+{
+    instance->Captureisr();
+}
+
+/*********************************************************************//**
+ * @brief        Capture interrupt service routine. Handles accumulation.
+ * 
+ * @param[in]    none
+ *                                 
+ * @return       none
+ **********************************************************************/
+void Capture::Captureisr(void) {
+    static unsigned int samplecount = 0;   // Counts passes
+    static unsigned int capturesum = 0;    // Accumulates the readings
+    
+    if(LPC_CT32B0->IR & IR_CR1INT) {
+        LPC_CT32B0->IR |= IR_CR1INT;       // Clear the interrupt request
+        capturesum += LPC_CT32B0->CR2;     // Read and accumulate the captured results
+                                            // It is necessary to use "CR2" in order to get the proper
+                                            //  offset from the base address (an issue with CMSIS)
+        if(++samplecount == Nsamples) {
+            capturedata = capturesum;      // Update the output data
+            samplecount = 0;               // Restart the pass counter
+            capturesum = 0;                // Re-initialize the running total
+            if(flag != 0) flag = -1;       // Make flag negative on an overrun
+            else flag = 1;                 // Set flag to 1 if no error
+        }     
+    }
+    return;
+}
\ No newline at end of file

diff -r 000000000000 -r 22c6b94e7da6 capturet0_11u24.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/capturet0_11u24.h	Thu Mar 13 17:52:43 2014 +0000
@@ -0,0 +1,133 @@
+ /* mbed Library - CaptureT0_11U24
+ * Copyright (c) 2014
+ * released under MIT license http://mbed.org/licence/mit
+ */
+ 
+/***********************************************************************//**
+ * @file        capturet1_11u24.h
+ * @brief       Header file for the CaptureT0_11U24 library. 
+ * @version     0.0
+ * @date        5 Feb 2014
+ * @author      
+ **************************************************************************/
+/***************************************************************************
+ * Revision     Date        Comments
+ *----------    --------    -----------------------------------------------
+ *
+ *  0.0         2/5/14    Initial creation
+ ***************************************************************************/
+
+#ifndef CAPTURET0_H
+#define CAPTURET0_H
+
+/* Includes ------------------------------------------------------------------- */
+#include "mbed.h"
+
+
+/* Public Types --------------------------------------------------------------- */
+
+
+/* Public Functions ----------------------------------------------------------- */
+/** @defgroup Capture_Public_Functions Capture Public Functions
+*/
+class Capture {
+public:
+
+/** Create a Capture object and configure it
+ *
+ * @param none
+ */
+Capture(void);
+
+/** Start capturing data. Accumulate the specified number of samples. 
+ * @param numsamples    The number of samples to be accumulated
+ * @return        None
+ */
+void Start(int numsamples);
+
+/** Check to see if a new count is ready. 
+ * 
+ * @return       (int) Status value. Negative means overrun.
+ */
+int Ready(void);
+
+/** Read (accumlated) sample count. 
+ * 
+ * @return       (unsigned int) Accumulated capture value
+ */
+unsigned int Read(void);
+
+
+
+/* Public Macros -------------------------------------------------------------- */
+
+
+
+
+private:
+static void _Captureisr(void);
+void Captureisr(void);  
+static Capture *instance;
+int flag;
+int channel;
+//int capturecount;
+unsigned int capturedata;
+int Nsamples;
+//int Nsamplebits;
+//int *flagaddresspointer;
+
+
+
+/* Private Macros ------------------------------------------------------------- */
+/* --------------------- BIT DEFINITIONS -------------------------------------- */
+/* Timer Capture Register Definitions --------------------- */
+
+/*********************************************************************//**
+ * Macro defines for CT32B0->IR Interrupt tegister
+ **********************************************************************/
+#define IR_CR1INT                   ((uint32_t)(1<<6))        /**< Interrupt flag for capture channel 1 */
+
+/*********************************************************************//**
+ * Macro defines for IOCON->PIO1_29 register bits LPC11U24
+ **********************************************************************/
+#define PIN_PULL_UP                     2UL
+#define PIN_REPEATER                    3UL
+#define PIN_NORESISTOR                  0UL
+#define PIN_PULL_DOWN                   1UL 
+
+/* FUNC bits */
+#define CT32B0_CAP1                     2UL
+
+/* MODE bits */
+#define CAP_PULLUP                 ((uint32_t)(PIN_PULL_UP<<3))          // Pull up on the CT32B0_CAP1 input pin
+
+/*********************************************************************//**
+ * Macro defines for SYSCON->SYSAHBCLKDIV register  bits LPC11U24
+ **********************************************************************/
+#define CT32B0_CLK_ENABLE          ((uint32_t)(1<<9))        /**< CT32B0 clock enable */ 
+
+/*********************************************************************//**
+ * Macro defines for CT32B0->TCR register  bits LPC11U24
+ **********************************************************************/
+#define TCR_CEN                         1UL
+
+
+/*********************************************************************//**
+ * Macro defines for CT32B0->CCR register  bits LPC11U24
+ **********************************************************************/
+#define CCR_CAP1RE                     ((uint32_t)(1<<6)) 
+#define CCR_CAP1FE                     ((uint32_t)(1<<7))
+#define CCR_CAP1I                      ((uint32_t)(1<<8))  
+
+/*********************************************************************//**
+ * Macro defines for CT32B0->CTCR register  bits LPC11U24
+ **********************************************************************/
+#define CTCR_CTM_TIMER                  0UL
+#define CTCR_ENCC                       ((uint32_t)(1<<4))
+#define CTCR_SEICC_CAP1RE               ((uint32_t)(4<<5))
+
+
+
+}; // End of Capture class information
+#endif /* CAPTURE_H */
+/* --------------------------------- End Of File ------------------------------ */