Added a timeout value to the TWI_StartTransmission() function, within which the addre...

Fixed TWI_StartTransmission() corrupting the contents of the GPIOR0 register.

diff --git a/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h b/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h
index 13db86e..2d8e6df 100644 (file)
--- a/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h
+++ b/LUFA/Drivers/Peripheral/AVRU4U6U7/TWI.h
@@ -56,6 +56,7 @@
                #include <avr/io.h>\r
                #include <stdbool.h>\r
                #include <util/twi.h>\r
+               #include <util/delay.h>\r
                \r
        /* Enable C linkage for C++ Compilers: */\r
                #if defined(__cplusplus)\r
@@ -131,10 +132,11 @@
                        /** Begins a master mode TWI bus communication with the given slave device address.\r
                         *\r
                         *  \param[in] SlaveAddress  Address of the slave TWI device to communicate with\r
+                        *  \param[in] TimeoutMS     Timeout period within which the slave must respond, in milliseconds\r
                         *\r
                         *  \return Boolean true if the device is ready for data, false otherwise\r
                         */\r
-                       bool TWI_StartTransmission(uint8_t SlaveAddress);\r
+                       bool TWI_StartTransmission(uint8_t SlaveAddress, uint8_t TimeoutMS);\r
 \r
        /* Disable C linkage for C++ Compilers: */\r
                #if defined(__cplusplus)\r

diff --git a/LUFA/Drivers/Peripheral/TWI.c b/LUFA/Drivers/Peripheral/TWI.c
index 6028bba..eb513c4 100644 (file)
--- a/LUFA/Drivers/Peripheral/TWI.c
+++ b/LUFA/Drivers/Peripheral/TWI.c
@@ -7,39 +7,58 @@
 \r
 #include "TWI.h"\r
 \r
-bool TWI_StartTransmission(uint8_t SlaveAddress)\r
+bool TWI_StartTransmission(uint8_t SlaveAddress, uint8_t TimeoutMS)\r
 {\r
        for (;;)\r
        {\r
-               uint8_t IterationsRemaining = 50;\r
-               bool    BusCaptured = false;\r
+               bool     BusCaptured = false;\r
+               uint16_t TimeoutRemaining;\r
 \r
-               while (IterationsRemaining-- && !BusCaptured)\r
+               TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));     \r
+\r
+               TimeoutRemaining = (TimeoutMS * 100);\r
+               while (TimeoutRemaining-- && !BusCaptured)\r
                {\r
-                       TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));     \r
-                       while (!(TWCR & (1 << TWINT)));\r
-                               \r
-                       switch (TWSR & TW_STATUS_MASK)\r
+                       if (TWCR & (1 << TWINT))\r
                        {\r
-                               case TW_START:\r
-                               case TW_REP_START:\r
-                                       BusCaptured = true;\r
-                                       break;\r
-                               case TW_MT_ARB_LOST:\r
-                                       continue;\r
-                               default:\r
-                                       return false;\r
+                               switch (TWSR & TW_STATUS_MASK)\r
+                               {\r
+                                       case TW_START:\r
+                                       case TW_REP_START:\r
+                                               BusCaptured = true;\r
+                                               break;\r
+                                       case TW_MT_ARB_LOST:\r
+                                               TWCR = ((1 << TWINT) | (1 << TWSTA) | (1 << TWEN));     \r
+                                               continue;\r
+                                       default:\r
+                                               TWCR = (1 << TWEN);\r
+                                               return false;\r
+                               }\r
                        }\r
+                       \r
+                       _delay_us(10);\r
                }\r
                \r
                if (!(BusCaptured))\r
-                 return false;\r
-                 \r
+               {\r
+                       TWCR = (1 << TWEN);\r
+                       return false;\r
+               }\r
+               \r
                TWDR = SlaveAddress;\r
                TWCR = ((1 << TWINT) | (1 << TWEN));\r
-               while (!(TWCR & (1 << TWINT)));\r
                \r
-               GPIOR0 = (TWSR & TW_STATUS_MASK);\r
+               TimeoutRemaining = (TimeoutMS * 100);\r
+               while (TimeoutRemaining--)\r
+               {\r
+                       if (TWCR & (1 << TWINT))\r
+                         break;\r
+                         \r
+                       _delay_us(10);\r
+               }\r
+               \r
+               if (!(TimeoutRemaining))\r
+                 return false;\r
 \r
                switch (TWSR & TW_STATUS_MASK)\r
                {\r
@@ -49,6 +68,6 @@ bool TWI_StartTransmission(uint8_t SlaveAddress)
                        default:\r
                                TWI_StopTransmission();\r
                                break;\r
-               }                 \r
+               }\r
        }\r
 }\r

diff --git a/LUFA/ManPages/ChangeLog.txt b/LUFA/ManPages/ChangeLog.txt
index 14f1a25..155afa0 100644 (file)
--- a/LUFA/ManPages/ChangeLog.txt
+++ b/LUFA/ManPages/ChangeLog.txt
@@ -15,9 +15,11 @@
   *  - AVRISP programmer project now has a more robust timeout system, allowing for a doubling of the software USART speed\r
   *    for PDI and TPI programming\r
   *  - Increased the speed of both software and hardware TPI/PDI programming modes of the AVRISP project\r
+  *  - Added a timeout value to the TWI_StartTransmission() function, within which the addressed device must respond\r
   *\r
   *  <b>Fixed:</b>\r
   *  - Fixed software PDI/TPI programming mode in the AVRISP project not correctly toggling just the clock pin\r
+  *  - Fixed TWI_StartTransmission() corrupting the contents of the GPIOR0 register\r
   *\r
   *  \section Sec_ChangeLog100219 Version 100219\r
   *\r

diff --git a/LUFA/ManPages/MigrationInformation.txt b/LUFA/ManPages/MigrationInformation.txt
index 2623640..8467e00 100644 (file)
--- a/LUFA/ManPages/MigrationInformation.txt
+++ b/LUFA/ManPages/MigrationInformation.txt
@@ -12,8 +12,11 @@
  *\r
  * \section Sec_MigrationXXXXXX Migrating from 100219 to XXXXXX\r
  *\r
+ *  <b>Non-USB Library Components</b>\r
+ *    - The \ref TWI_StartTransmission() function now takes in a timeout period, expressed in milliseconds, within which the addressed\r
+ *      device must respond or the function will abort.\r
+ *\r
  * \section Sec_Migration100219 Migrating from 091223 to 100219\r
- *    - (None)\r
  *\r
  *  <b>Non-USB Library Components</b>\r
  *    - Due to some ADC channels not being identical to their ADC MUX selection masks for single-ended conversions on some AVR models,\r

diff --git a/Projects/TemperatureDataLogger/Lib/DS1307.c b/Projects/TemperatureDataLogger/Lib/DS1307.c
index 64e03df..0c1d98f 100644 (file)
--- a/Projects/TemperatureDataLogger/Lib/DS1307.c
+++ b/Projects/TemperatureDataLogger/Lib/DS1307.c
@@ -21,7 +21,7 @@ void DS1307_SetDate(uint8_t Day, uint8_t Month, uint8_t Year)
        CurrentRTCDate.Byte3.TenYear  = (Year / 10);\r
        CurrentRTCDate.Byte3.Year     = (Year % 10);\r
 \r
-       if (TWI_StartTransmission(DS1307_ADDRESS_WRITE))\r
+       if (TWI_StartTransmission(DS1307_ADDRESS_WRITE, 10))\r
        {\r
                TWI_SendByte(DS1307_DATEREG_START);\r
                TWI_SendByte(CurrentRTCDate.Byte1.IntVal);\r
@@ -48,7 +48,7 @@ void DS1307_SetTime(uint8_t Hour, uint8_t Minute, uint8_t Second)
        CurrentRTCTime.Byte3.Hour    = (Hour % 10);\r
        CurrentRTCTime.Byte3.TwelveHourMode = false;\r
        \r
-       if (TWI_StartTransmission(DS1307_ADDRESS_WRITE))\r
+       if (TWI_StartTransmission(DS1307_ADDRESS_WRITE, 10))\r
        {\r
                TWI_SendByte(DS1307_TIMEREG_START);\r
                TWI_SendByte(CurrentRTCTime.Byte1.IntVal);\r
@@ -68,7 +68,7 @@ void DS1307_GetDate(uint8_t* Day, uint8_t* Month, uint8_t* Year)
        return;\r
 #endif\r
 \r
-       if (TWI_StartTransmission(DS1307_ADDRESS_WRITE))\r
+       if (TWI_StartTransmission(DS1307_ADDRESS_WRITE, 10))\r
        {\r
                TWI_SendByte(DS1307_DATEREG_START);\r
                \r
@@ -77,7 +77,7 @@ void DS1307_GetDate(uint8_t* Day, uint8_t* Month, uint8_t* Year)
 \r
        DS1307_DateRegs_t CurrentRTCDate;\r
 \r
-       if (TWI_StartTransmission(DS1307_ADDRESS_READ))\r
+       if (TWI_StartTransmission(DS1307_ADDRESS_READ, 10))\r
        {\r
                TWI_ReceiveByte(&CurrentRTCDate.Byte1.IntVal, false);\r
                TWI_ReceiveByte(&CurrentRTCDate.Byte2.IntVal, false);\r
@@ -100,7 +100,7 @@ void DS1307_GetTime(uint8_t* Hour, uint8_t* Minute, uint8_t* Second)
        return;\r
 #endif\r
 \r
-       if (TWI_StartTransmission(DS1307_ADDRESS_WRITE))\r
+       if (TWI_StartTransmission(DS1307_ADDRESS_WRITE, 10))\r
        {\r
                TWI_SendByte(DS1307_TIMEREG_START);\r
                \r
@@ -109,7 +109,7 @@ void DS1307_GetTime(uint8_t* Hour, uint8_t* Minute, uint8_t* Second)
        \r
        DS1307_TimeRegs_t CurrentRTCTime;\r
 \r
-       if (TWI_StartTransmission(DS1307_ADDRESS_READ))\r
+       if (TWI_StartTransmission(DS1307_ADDRESS_READ, 10))\r
        {\r
                TWI_ReceiveByte(&CurrentRTCTime.Byte1.IntVal, false);\r
                TWI_ReceiveByte(&CurrentRTCTime.Byte2.IntVal, false);\r

diff --git a/Projects/TemperatureDataLogger/makefile b/Projects/TemperatureDataLogger/makefile
index 8fd2c29..f48e155 100644 (file)
--- a/Projects/TemperatureDataLogger/makefile
+++ b/Projects/TemperatureDataLogger/makefile
@@ -193,7 +193,7 @@ CSTANDARD = -std=gnu99
 \r
 # Place -D or -U options here for C sources\r
 CDEFS  = -DF_CPU=$(F_CPU)UL -DF_CLOCK=$(F_CLOCK)UL -DBOARD=BOARD_$(BOARD) $(LUFA_OPTS)\r
-CDEFS += -DDUMMY_RTC\r
+#CDEFS += -DDUMMY_RTC\r
 \r
 \r
 # Place -D or -U options here for ASM sources\r