Wim Huiskamp / SC16IS750

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Dependents:   SC16IS750_Test mbed_SC16IS750 Xadow_SC16IS750_Test Xadow_MPU9150AHRS

Files at this revision

API Documentation at this revision

Revision 5:ff3e57bebb6a, committed 2014-12-24

Comitter:
wim
Date:
Wed Dec 24 01:05:49 2014 +0000
Parent:
4:12446ee9f9c8
Commit message:
Added Repeated Start for I2C readRegister(). Set I2C clock at 100kb/s. Fixed and added some comments.

Changed in this revision

SC16IS750.cpp Show annotated file Show diff for this revision Revisions of this file
SC16IS750.h Show annotated file Show diff for this revision Revisions of this file 
--- a/SC16IS750.cpp	Mon Dec 22 19:04:38 2014 +0000
+++ b/SC16IS750.cpp	Wed Dec 24 01:05:49 2014 +0000
@@ -3,6 +3,7 @@
  *                      https://forum.sparkfun.com/viewtopic.php?f=13&t=21846
  *   v0.2 WH, Feb 2014, Added Doxygen Documentation, Added Hardware Reset pin methods. 
  *   v0.3 WH, Dec 2014, Added support for SC16IS752 dual UART.  
+ *   v0.4 WH, Dec 2014, Added Repeated Start for I2C readRegister(). Set I2C clock at 100kb/s. Fixed and added some comments.
  *
  * 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,
@@ -360,7 +361,6 @@
 }
 
 
-
 /**
   * Check that UART is connected and operational.
   *  @param  none
@@ -376,7 +376,6 @@
 }
 
 
-
 /** Determine if there is a character available to read.
   * This is data that's already arrived and stored in the receive
   * buffer (which holds 64 chars).
@@ -392,7 +391,6 @@
   else {
     return 0; 
   }
-
 }
 
 /** Determine how many characters are available to read.
@@ -585,10 +583,9 @@
 }
 
 
-
-
 /** Set direction of I/O port pins.
   * This method is specific to the SPI-I2C UART and not found on the 16750
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B.
   *   @param  bits Bitpattern for I/O (1=output, 0=input)
   *   @return none
   */
@@ -598,6 +595,7 @@
 
 /** Set bits of I/O port pins.
   * This method is specific to the SPI-I2C UART and not found on the 16750
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B.  
   *   @param  bits Bitpattern for I/O (1= set output bit, 0 = clear output bit)
   *   @return none
   */
@@ -607,6 +605,7 @@
 
 /** Get bits of I/O port pins.
   * This method is specific to the SPI-I2C UART and not found on the 16750
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B.  
   *   @param  none
   *   @return bits Bitpattern for I/O (1= bit set, 0 = bit cleared)
   */
@@ -617,6 +616,7 @@
 
 /** Software Reset SC16IS750 device.
   * This method is specific to the SPI-I2C UART and not found on the 16750
+  * Note: The SC16IS752 does not have separate Reset for Channel_A and Channel_B.  
   *   @param  none
   *   @return none
   */
@@ -675,9 +675,6 @@
    if (_reset != NULL) {delete _reset;}  // Reset pin
 }
 
-
-
-
 /** Write value to internal register.
   * Pure virtual, must be declared in derived class.   
   *   @param registerAddress   The address of the Register (enum RegisterName)
@@ -776,7 +773,8 @@
   */  
 SC16IS750_I2C::SC16IS750_I2C(I2C *i2c, uint8_t deviceAddress, PinName rst) : _i2c(i2c), _slaveAddress(deviceAddress & 0xFE) {
 
-  _i2c->frequency(400000);
+//  _i2c->frequency(400000);
+  _i2c->frequency(100000);  
  
   // The hardware Reset pin is optional. Test and make sure whether it exists or not to prevent illegal access.
   if (rst != NC) {
@@ -832,7 +830,8 @@
     
    w[0] = registerAddress;
     
-   _i2c->write( _slaveAddress, w, 1 );
+//   _i2c->write( _slaveAddress, w, 1 );
+   _i2c->write(_slaveAddress, w, 1, true);   //Repeated Start   
    _i2c->read( _slaveAddress, r, 1 );
 
    return ( r[0] );
@@ -912,6 +911,8 @@
 
 
 /** Create an SC16IS752_SPI object using a specified SPI bus and CS
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B. 
+  * Note: The SC16IS752 does not have separate Reset for Channel_A and Channel_B.     
   *
   * @param SPI &spi the SPI port to connect to 
   * @param cs  Pinname of the CS pin (active low)
@@ -952,8 +953,6 @@
 }
 
 
-
-
 /** Write value to internal register.
   * Pure virtual, must be declared in derived class.   
   *   @param registerAddress   The address of the Register (enum RegisterName)
@@ -1044,6 +1043,8 @@
 //
 
 /** Create a SC16IS752_I2C object for a bridge between I2C and a Serial port
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B. 
+  * Note: The SC16IS752 does not have separate Reset for Channel_A and Channel_B.     
   *
   * @param I2C &i2c the I2C port to connect to 
   * @param char deviceAddress the I2C slave address of the SC16IS750
@@ -1052,8 +1053,9 @@
   */  
 SC16IS752_I2C::SC16IS752_I2C(I2C *i2c, uint8_t deviceAddress, PinName rst, ChannelName channel) : _i2c(i2c), _slaveAddress(deviceAddress & 0xFE), _channel(channel) {
 
-  _i2c->frequency(400000);
- 
+//  _i2c->frequency(400000);
+  _i2c->frequency(100000);
+   
   // The hardware Reset pin is optional. Test and make sure whether it exists or not to prevent illegal access.
   if (rst != NC) {
     _reset = new DigitalOut(rst);   //Construct new pin 
@@ -1108,8 +1110,9 @@
     
    w[0] = registerAddress | _channel;
     
-   _i2c->write( _slaveAddress, w, 1 );
-   _i2c->read( _slaveAddress, r, 1 );
+//   _i2c->write( _slaveAddress, w, 1 );
+   _i2c->write(_slaveAddress, w, 1, true);   //Repeated Start
+   _i2c->read(_slaveAddress, r, 1 );
 
    return ( r[0] );
 }

--- a/SC16IS750.h	Mon Dec 22 19:04:38 2014 +0000
+++ b/SC16IS750.h	Wed Dec 24 01:05:49 2014 +0000
@@ -3,6 +3,7 @@
  *                      https://forum.sparkfun.com/viewtopic.php?f=13&t=21846
  *   v0.2 WH, Feb 2014, Added Doxygen Documentation, Added Hardware Reset pin methods.
  *   v0.3 WH, Dec 2014, Added support for SC16IS752 dual UART. 
+ *   v0.4 WH, Dec 2014, Added Repeated Start for I2C readRegister(). Set I2C clock at 100kb/s. Fixed and added some comments. 
  *
  * 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,
@@ -349,7 +350,7 @@
         TXLVL       = 0x08 << 3, /* TX FIFO Level register - Read only    */
         RXLVL       = 0x09 << 3, /* RX FIFO Level register - Read only    */
         IODIR       = 0x0A << 3, /* IO Pin Direction reg   - RD/WR access */
-        IOSTATE     = 0x0B << 3, /* IO Pin State reg       - Read only    */
+        IOSTATE     = 0x0B << 3, /* IO Pin State reg       - RD/WR access */
         IOINTENA    = 0x0C << 3, /* IO Interrupt Enable    - RD/WR access */
 //        reserved    = 0x0D << 3,
         IOCTRL      = 0x0E << 3, /* IO Control register    - RD/WR access */
@@ -568,6 +569,7 @@
 
 /** Set direction of I/O port pins.
   * This method is specific to the SPI-I2C UART and not found on the 16750
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B.    
   *   @param  bits Bitpattern for I/O (1=output, 0=input)
   *   @return none
   */
@@ -575,6 +577,7 @@
 
 /** Set bits of I/O port pins.
   * This method is specific to the SPI-I2C UART and not found on the 16750
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B.    
   *   @param  bits Bitpattern for I/O (1= set output bit, 0 = clear output bit)
   *   @return none
   */
@@ -582,6 +585,7 @@
 
 /** Get bits of I/O port pins.
   * This method is specific to the SPI-I2C UART and not found on the 16750
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B.    
   *   @param  none
   *   @return bits Bitpattern for I/O (1= bit set, 0 = bit cleared)
   */
@@ -590,6 +594,7 @@
 
 /** Software Reset SC16IS750 device.
   * This method is specific to the SPI-I2C UART and not found on the 16750
+  * Note: The SC16IS752 does not have separate Reset for Channel_A and Channel_B.    
   *   @param  none
   *   @return none
   */
@@ -784,7 +789,7 @@
  * #include "SC16IS750.h"
  *
  * I2C i2c(PTE0, PTE1);       //SDA, SCL
- * SC16IS750_I2C serial_i2c(&i2c, DEFAULT_SC16IS750_ADDR);
+ * SC16IS750_I2C serial_i2c(&i2c, SC16IS750_DEFAULT_ADDR);
  *
  * Serial pc(USBTX,USBRX);
  *
@@ -903,6 +908,8 @@
 public:
 
 /** Create an SC16IS752_SPI object using a specified SPI bus and CS
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B.  
+  * Note: The SC16IS752 does not have separate Reset for Channel_A and Channel_B.    
   *
   * @param SPI &spi the SPI port to connect to 
   * @param cs  Pinname of the CS pin (active low)
@@ -965,7 +972,6 @@
 
 // Save Channel setting
   ChannelName _channel; 
-
 };
 
 
@@ -977,7 +983,7 @@
  * #include "SC16IS750.h"
  *
  * I2C i2c(PTE0, PTE1);       //SDA, SCL
- * SC16IS752_I2C serial_i2c(&i2c, DEFAULT_SC16IS750_ADDR, NC, SC16IS750::Channel_A);
+ * SC16IS752_I2C serial_i2c(&i2c, SC16IS750_DEFAULT_ADDR, NC, SC16IS750::Channel_A);
  *
  * Serial pc(USBTX,USBRX);
  *
@@ -1000,6 +1006,8 @@
 public:
 
 /** Create an SC16IS752_I2C object using a specified I2C bus, slaveaddress and Channel
+  * Note: The SC16IS752 does not have separate GPIOs for Channel_A and Channel_B. 
+  * Note: The SC16IS752 does not have separate Reset for Channel_A and Channel_B.     
   *
   * @param I2C &i2c the I2C port to connect to 
   * @param char deviceAddress the address of the SC16IS750