Enable digitalRead on output pins, only enable pullup or pulldown in digitalWrite if pin is not output. arduino#56 arduino#79 arduino#94 arduino#101

Author: mattairtech

README.md

@@ -266,18 +266,25 @@ everything else (ie: W) resides in flash (in most cases).
 
 #### Windows
 
-There are currently four USB composite device combinations that include CDC as well as a CDC only device.
-Drivers are required for each of these five devices. The CDC only driver is required by the bootloader.
-The drivers are signed and support both 32 and 64 bit versions of Windows XP (SP3), Vista, 7, 8, and 10.
+Prior to core version 1.6.6-mt1, sketches compiled with both CDC and HID USB code by default, thus requiring a CDC
+driver for the bootloader and a CDC-HID driver for sketches. Now that PluggableUSB is supported, sketches compile
+with only CDC code by default. Thus, only one driver is needed. Since HID and MIDI are currently supported (and
+MSD potentially in the future), driver installation will be required for each different combination of USB devices.
+There are currently four USB composite device combinations that include CDC as well as a CDC only device. Each
+supported combination has a unique USB VID:PID pair, and these are listed in the .inf file. Once the first device
+is installed (the CDC only device), future installations *might* be automatic, otherwise, you may direct the
+installer to the same .inf file. The drivers are signed and support both 32 and 64 bit versions of Windows XP(SP3),
+Vista, 7, 8, and 10.
+
 
 1. If you do not already have the SAM-BA bootloader installed, see below.
 2. Download https://www.mattairtech.com/software/MattairTech_CDC_Driver_Signed.zip and unzip into any folder.
 3. Plug in the board while holding down button A to enter the bootloader. The LED should light.
 4. Windows will detect the board. Point the installer to the folder from above to install the bootloader driver.
 5. If you don't intend on using Arduino, you can skip the rest of this list. See Using Bossac Standalone below.
 6. If you do not already have the test firmware installed (comes preinstalled), see Using Bossac Standalone below.
-7. Press the reset button to run the test firmware (blink sketch with CDC-HID).
-8. Windows will detect the board. Point the installer to the folder from above to install the sketch driver.
+7. Press the reset button to run the test firmware (blink sketch).
+8. Windows will detect the board. Point the installer to the above folder to install the sketch driver (if needed).
 9. Continue with SAMD Core Installation below.
 
 #### Linux
@@ -291,14 +298,17 @@ The drivers are signed and support both 32 and 64 bit versions of Windows XP (SP
 
 #### OS X
 
+UNTESTED
 1. As of this writing, only the 256 KB chip variants work with the OS X version of the upload tool, bossac.
 2. First, you will need to open boards.txt and change mattairtech_mt_d21e_bl8k.upload.tool to equal arduino:bossac.
 3. Open platform.txt and change tools.bossac.path to equal{runtime.tools.bossac-1.6.1-arduino.path}.
-4. No driver installation is needed. You may get a dialog box asking if you wish to open the “Network Preferences”:
+4. No driver installation is needed.
+5. Plug in the board. You may get a dialog box asking if you wish to open the “Network Preferences”:
    * Click the "Network Preferences..." button, then click "Apply".
    * The board will show up as “Not Configured”, but it will work fine.
 5. Continue with SAMD Core Installation below.
 
+
 ### SAMD Core Installation
 
 * To update from a previous version, click on MattairTech SAMD Boards in Boards Manager, then click Update.
@@ -319,6 +329,16 @@ The drivers are signed and support both 32 and 64 bit versions of Windows XP (SP
 13. You can now upload your own sketch.
 
 
+### Uploading the First Sketch
+
+1. In the Arduino IDE 1.6.7 (or above), open File->Examples->01.Basics->Blink.
+2. Change the three instances of '13' to 'LED_BUILTIN'.
+3. Be sure the correct options are selected in the Tools menu (see AVR Core Installation above).
+4. With the board plugged in, select the correct port from Tools->Port.
+5. Click the Upload button. After compiling, the sketch should be transferred to the board.
+6. Once the bootloader exits, the blink sketch should be running.
+
+
 ## SAM-BA USB CDC Bootloader (Arduino compatible)
 
 The SAM-BA bootloader has both a CDC USB interface, and a UART interface (MT-D21E: TX: pin 10, RX: pin 11). It is
@@ -361,6 +381,7 @@ When the Arduino IDE initiates the bootloader, the following procedure is used:
 3. The board is reset. The bootloader (which always runs first) detects the blank flah row, so bootloader operation resumes.
 4. Opening and closing the port at a baud rate other than 1200bps will not erase or reset the SAMD.
 
+
 ### Bootloader Firmware Installation
 
 #### Bootloader Installation Using the Arduino IDE
@@ -383,6 +404,7 @@ When the Arduino IDE initiates the bootloader, the following procedure is used:
    * You can optionally set the EEPROM bits or anything else. The Arduino installation method uses factory defaults.
 4. Continue with driver installation above.
 
+
 ### Using Bossac Standalone
 
 When using Bossac standalone, you will need to ensure that your application starts at 0x00002000 for 8 KB bootloaders,
@@ -408,13 +430,13 @@ As an example, bossac will be used to upload the test firmware (blink sketch):
 1. Download firmware from https://www.mattairtech.com/software/SAM-BA-bootloader-test-firmware.zip and unzip.
 2. If you have not already installed the bootloader driver, see Driver Installation above.
 3. Be sure there is a binary that matches your chip. On the command line (change the binary to match yours):
-4. On Linux --port might be /dev/ttyACM0. If the device is not found, remove the --port argument for auto-detection.
 
 ```
 bossac.exe -d --port=COM5 -U true -i -e -w -v Blink_Demo_ATSAMD21E18A.bin -R
 ```
+4. On Linux --port might be /dev/ttyACM0. If the device is not found, remove the --port argument for auto-detection.
 5. See http://manpages.ubuntu.com/manpages/vivid/man1/bossac.1.html for details.
-6. Continue with the CDC-HID driver installation above (optional).
+6. The board should reset automatically and the sketch should be running.
 
 
 
@@ -504,25 +526,29 @@ bossac.exe -d --port=COM5 -U true -i -e -w -v Blink_Demo_ATSAMD21E18A.bin -R
 
 ## Possible Future Additions
 
-* USB Host mode CDC ACM
+* SAML21 support in the works
+* Timer library in the works (like TimerOne, plus input capture and possibly waveform extensions)
+* USB Host mode CDC ACM (partially complete; BSD-like license?)
 * Features for lower power consumption (library?)
 * Enhanced SD card library
 * Optional use of single on-board LED as USB activity LED
 * Replace pulse with timer capture
 * MSC (Mass Storage) USB Device Class
 * Polyphonic tone
 * Better OS X support
+* Wired-AND, Wired-OR for port pins
+* High-speed port pin access (IOBUS)
 * Libraries for some hardware I plan on using:
-  TFT LCD
-  Motor controller
+  TFT LCD (CFAF128128B-0145T)
+  Motor controller (LV8711T)
   IR decoder
   I2S DAC/AMP and I2S MEMS microphone
   Battery management IC
   XBee/Xbee Pro devices
   RS485
   Several I2C (Wire) sensor devices: 
-    Accelerometer/gyro/magnetometer
-    Barometer/altimeter
+    Accelerometer/magnetometer (LSM303CTR)
+    Barometer/altimeter (LPS22HBTR)
     Humidity/temperature
     Light/color sensor
 

cores/arduino/Uart.cpp

@@ -36,7 +36,6 @@ void Uart::begin(unsigned long baudrate)
 
 void Uart::begin(unsigned long baudrate, uint8_t config)
 {
-  pinMode(uc_pinRX,INPUT_PULLUP);//Rx pin set INPUT_PULLUP mode
   pinPeripheral(uc_pinRX, PIO_SERCOM);
   pinPeripheral(uc_pinTX, PIO_SERCOM);
 

cores/arduino/WVariant.h

@@ -161,6 +161,8 @@ typedef enum _EPioType
   PIO_AC_GCLK=12,                     /* The pin is controlled by the AC_GCLK peripheral (output). */
 
   PIO_MULTI,                          /* The pin can be configured to any type based on the attributes. */
+  
+  PIO_STARTUP,                        /* Used as parameter to pinPeripheral() only to set startup state (enable INEN only) */
 } EPioType ;
 
 /**
@@ -228,6 +230,10 @@ typedef enum _EPioPeripheral
 #define PER_ATTR_OUTPUT_TYPE_BUSKEEPER      (3UL<<3)
 #define PER_ATTR_OUTPUT_TYPE_MASK           (3UL<<3)
 
+#define PER_ATTR_INPUT_SYNCHRONIZER_ON_DEMAND     (0UL<<5)
+#define PER_ATTR_INPUT_SYNCHRONIZER_ALWAYS_ON     (1UL<<5)
+#define PER_ATTR_INPUT_SYNCHRONIZER_MASK          (1UL<<5)
+
 
 /* Types used for the table below
  * This struct MUST be 12 bytes long (elements are ordered to prevent unaligned access).

cores/arduino/wiring.c

@@ -96,11 +96,11 @@ void init( void )
   // Clock ADC/DAC for Analog
   PM->APBCMASK.reg |= PM_APBCMASK_ADC | PM_APBCMASK_DAC ;
 
-  // Setup all pins (digital and analog) in INPUT mode (default is nothing)
-  // for ( ul = 0 ; ul < NUM_DIGITAL_PINS ; ul++ )
-  // {
-  //	  pinMode( ul, INPUT ) ;
-  // }
+  //Setup all pins (digital and analog) in STARTUP mode (enable INEN only)
+  for ( ul = 0 ; ul < NUM_DIGITAL_PINS ; ul++ )
+  {
+  	pinMode( ul, PIO_STARTUP ) ;
+  }
 
   // Initialize Analog Controller
   // Setting clock

cores/arduino/wiring_digital.c

@@ -39,29 +39,38 @@ void digitalWrite( uint32_t ulPin, uint32_t ulVal )
   uint32_t pinAttribute = g_APinDescription[ulPin].ulPinAttribute;
   uint8_t pinPort = g_APinDescription[ulPin].ulPort;
   uint8_t pinNum = g_APinDescription[ulPin].ulPin;
-  uint8_t pullConfig = PORT->Group[pinPort].PINCFG[pinNum].reg;
-  
-  // Enable pull resistor if pin attributes allow
-  if ( (ulVal == HIGH && (pinAttribute & PIN_ATTR_INPUT_PULLUP)) || (ulVal == LOW && (pinAttribute & PIN_ATTR_INPUT_PULLDOWN)) )
-  {
-    pullConfig |= (uint8_t)(PORT_PINCFG_PULLEN) ;
+  uint8_t pinConfig = PORT->Group[pinPort].PINCFG[pinNum].reg;
+  uint8_t pinDir = PORT->Group[pinPort].DIR[pinNum].reg;
+  uint8_t pinOut = PORT->Group[pinPort].OUT[pinNum].reg;
+
+  // Enable pull resistor if pin attributes allow and only if pin is not configured as output
+  // Note that most pins should use PIN_ATTR_DIGITAL, which includes both PIN_ATTR_INPUT_PULLUP and PIN_ATTR_INPUT_PULLDOWN.
+  if ( pinDir == 0 ) { // pin DIR is input
+     if ( ulVal == HIGH )
+     {
+       if ( (pinOut == 1 && (pinAttribute & PIN_ATTR_INPUT_PULLUP)) || (pinOut == 0 && (pinAttribute & PIN_ATTR_INPUT_PULLDOWN)) )
+       {
+         pinConfig |= (uint8_t)(PORT_PINCFG_PULLEN) ;
+       }
+     }
+     else
+     {
+       pinConfig &= ~(uint8_t)(PORT_PINCFG_PULLEN) ;
+     }
+     
+     PORT->Group[pinPort].PINCFG[pinNum].reg = pinConfig ;
   }
+  // Set or clear OUT register only when pin DIR is set to output.
+  // Pull direction (pullup or pulldown) is now set with pinMode only.
   else
   {
-    pullConfig &= ~(uint8_t)(PORT_PINCFG_PULLEN) ;
-  }
-
-  PORT->Group[pinPort].PINCFG[pinNum].reg = pullConfig ;
-
-  switch ( ulVal )
-  {
-    case LOW:
-      PORT->Group[pinPort].OUTCLR.reg = (1ul << pinNum) ;
-    break ;
-
-    default:
+    if ( ulVal == HIGH ) {
       PORT->Group[pinPort].OUTSET.reg = (1ul << pinNum) ;
-    break ;
+    }
+    else
+    {
+      PORT->Group[pinPort].OUTCLR.reg = (1ul << pinNum) ;
+    }
   }
 
   return ;

cores/arduino/wiring_private.c

@@ -37,14 +37,14 @@ int pinPeripheral( uint32_t ulPin, uint32_t ulPeripheral )
     return -1 ;
   }
 
-  // If pinType is not PIO_MULTI in the pinDescription table, then it must match ulPeripheral
-  if ( pinType != PIO_MULTI && pinType != ulPeripheral )
+  // If pinType is not PIO_MULTI or PIO_STARTUP in the pinDescription table, then it must match ulPeripheral
+  if ( pinType != PIO_MULTI && pinType != PIO_STARTUP && pinType != ulPeripheral )
   {
     return -1 ;
   }
 
   // Make sure ulPeripheral is listed in the attributes
-  if ( !(pinAttribute & (1UL << ulPeripheral)) )
+  if ( !(pinAttribute & (1UL << ulPeripheral)) && pinType != PIO_STARTUP )
   {
     return -1 ;
   }
@@ -123,10 +123,14 @@ int pinPeripheral( uint32_t ulPin, uint32_t ulPeripheral )
 
   uint8_t pinPort = g_APinDescription[ulPin].ulPort;
   uint8_t pinNum = g_APinDescription[ulPin].ulPin;
-  uint8_t pinCfg = PORT_PINCFG_INEN;
+  uint8_t pinCfg = PORT_PINCFG_INEN;	// INEN should be enabled for both input and output (but not analog)
 
   switch ( ulPeripheral )
   {
+    case PIO_STARTUP:
+      PORT->Group[pinPort].PINCFG[pinNum].reg=(uint8_t)pinCfg ; // Just enable INEN
+    break;
+    
     // Set pin mode according to chapter '22.6.3 I/O Pin Configuration'
     case PIO_INPUT:
     case PIO_INPUT_PULLUP:
@@ -151,7 +155,6 @@ int pinPeripheral( uint32_t ulPin, uint32_t ulPeripheral )
     break ;
 
     case PIO_OUTPUT:
-      pinCfg = 0;
       if ( (peripheralAttribute & PER_ATTR_DRIVE_MASK) == PER_ATTR_DRIVE_STRONG )
       {
         pinCfg |= PORT_PINCFG_DRVSTR;
@@ -162,10 +165,12 @@ int pinPeripheral( uint32_t ulPin, uint32_t ulPeripheral )
     break ;
 
 
-    case PIO_EXTINT:
     case PIO_ANALOG_ADC:
     case PIO_ANALOG_DAC:
     case PIO_ANALOG_REF:
+	pinCfg = 0;	// Disable INEN with analog
+	
+    case PIO_EXTINT:
     case PIO_TIMER_PWM:
     case PIO_TIMER_CAPTURE:
     case PIO_SERCOM: