UART1 buffered serial driver, requires RTOS
Dependents: Serial_interrupts_buffered HARP2 HARP3
Buffered serial UART1 - Setup to work with UART1 (p13,p14)
Uses RTOS to block current thread.
Reference: http://mbed.org/users/tylerjw/notebook/buffered-serial-with-rtos/
Revision 4:d3122119f92b, committed 2012-12-17
- Comitter:
- tylerjw
- Date:
- Mon Dec 17 22:35:51 2012 +0000
- Parent:
- 3:a4a21e18acd1
- Commit message:
- naming conventions and documentation
Changed in this revision
buffered_serial.cpp | Show annotated file Show diff for this revision Revisions of this file |
buffered_serial.h | Show annotated file Show diff for this revision Revisions of this file |
diff -r a4a21e18acd1 -r d3122119f92b buffered_serial.cpp --- a/buffered_serial.cpp Thu Dec 13 06:53:43 2012 +0000 +++ b/buffered_serial.cpp Mon Dec 17 22:35:51 2012 +0000 @@ -1,11 +1,38 @@ +/* + * @file buffered_serial.cpp + * @author Tyler Weaver + * + * @section LICENSE + * + * 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, + * including without limitation the rights to use, copy, modify, merge, publish, distribute, + * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or + * substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING + * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * @section DESCRIPTION + * + * Buffered serial UART1 - Setup to work with UART1 (p13,p14) + * + * Uses RTOS to block current thread. + */ #include "buffered_serial.h" -BufferedSerial::BufferedSerial(PinName tx, PinName rx) : Serial(tx,rx), /*led1(LED1), led2(LED2),*/ rx_sem(0), tx_sem(0) +BufferedSerial::BufferedSerial() : Serial(p13,p14), /*led1(LED1), led2(LED2),*/ rx_sem_(0), tx_sem_(0) { - tx_in=0; - tx_out=0; - rx_in=0; - rx_out=0; + tx_in_=0; + tx_out_=0; + rx_in_=0; + rx_out_=0; device_irqn = UART1_IRQn; @@ -15,33 +42,33 @@ } // Copy tx line buffer to large tx buffer for tx interrupt routine -void BufferedSerial::send_line(char *c) +void BufferedSerial::put_line(char *c) { int i; char temp_char; bool empty; i = 0; - strncpy(tx_line,c,LINE_SIZE); + strncpy(tx_line_,c,LINE_SIZE); // Start Critical Section - don't interrupt while changing global buffer variables NVIC_DisableIRQ(device_irqn); - empty = (tx_in == tx_out); - while ((i==0) || (tx_line[i-1] != '\n')) { + empty = (tx_in_ == tx_out_); + while ((i==0) || (tx_line_[i-1] != '\n')) { // Wait if buffer full if (IS_TX_FULL) { // End Critical Section - need to let interrupt routine empty buffer by sending NVIC_EnableIRQ(device_irqn); //while (IS_TX_FULL) ; // buffer is full - tx_sem.wait(); + tx_sem_.wait(); // Start Critical Section - don't interrupt while changing global buffer variables NVIC_DisableIRQ(device_irqn); } - tx_buffer[tx_in] = tx_line[i]; + tx_buffer_[tx_in_] = tx_line_[i]; i++; - tx_in = NEXT(tx_in); + tx_in_ = NEXT(tx_in_); } if (Serial::writeable() && (empty)) { - temp_char = tx_buffer[tx_out]; - tx_out = NEXT(tx_out); + temp_char = tx_buffer_[tx_out_]; + tx_out_ = NEXT(tx_out_); // Send first character to start tx interrupts, if stopped LPC_UART1->THR = temp_char; } @@ -50,40 +77,39 @@ } // Read a line from the large rx buffer from rx interrupt routine -void BufferedSerial::read_line(char *c) +void BufferedSerial::get_line(char *c) { int i; i = 0; // Start Critical Section - don't interrupt while changing global buffer variables NVIC_DisableIRQ(device_irqn); // Loop reading rx buffer characters until end of line character - while ((i==0) || (rx_line[i-1] != '\n')) { + while ((i==0) || (rx_line_[i-1] != '\n')) { // Wait if buffer empty if (IS_RX_EMPTY) { // buffer empty // End Critical Section - need to allow rx interrupt to get new characters for buffer NVIC_EnableIRQ(device_irqn); - //while (rx_in == rx_out) ; // buffer empty - rx_sem.wait(); + + rx_sem_.wait(); // Start Critical Section - don't interrupt while changing global buffer variables NVIC_DisableIRQ(device_irqn); } else { - rx_sem.wait(); + rx_sem_.wait(); } - rx_line[i] = rx_buffer[rx_out]; + rx_line_[i] = rx_buffer_[rx_out_]; i++; - rx_out = NEXT(rx_out); - + rx_out_ = NEXT(rx_out_); + // prevent overflow on rx_line - if(i == LINE_SIZE) - { + if(i == LINE_SIZE) { i--; break; } } - rx_line[i++] = 0; + rx_line_[i++] = 0; // End Critical Section NVIC_EnableIRQ(device_irqn); - strncpy(c,rx_line,i); + strncpy(c,rx_line_,i); } // Interupt Routine to read in data from serial port @@ -92,9 +118,9 @@ uint32_t IRR1 = LPC_UART1->IIR; // led1=1; while (readable() && !(IS_RX_FULL)) { - rx_buffer[rx_in] = LPC_UART1->RBR; - rx_in = NEXT(rx_in); - rx_sem.release(); + rx_buffer_[rx_in_] = LPC_UART1->RBR; + rx_in_ = NEXT(rx_in_); + rx_sem_.release(); } // led1=0; } @@ -104,11 +130,11 @@ { uint32_t IRR = LPC_UART1->IIR; // led2=1; - while ((writeable()) && (tx_in != tx_out)) { // while serial is writeable and there are still characters in the buffer - LPC_UART1->THR = tx_buffer[tx_out]; // send the character - tx_out = NEXT(tx_out); + while ((writeable()) && (tx_in_ != tx_out_)) { // while serial is writeable and there are still characters in the buffer + LPC_UART1->THR = tx_buffer_[tx_out_]; // send the character + tx_out_ = NEXT(tx_out_); } if(!IS_TX_FULL) // if not full - tx_sem.release(); + tx_sem_.release(); // led2=0; } \ No newline at end of file
diff -r a4a21e18acd1 -r d3122119f92b buffered_serial.h --- a/buffered_serial.h Thu Dec 13 06:53:43 2012 +0000 +++ b/buffered_serial.h Mon Dec 17 22:35:51 2012 +0000 @@ -1,6 +1,30 @@ /* - Buffered serial 1 - Setup to work with UART1 (p13,p14) -*/ + * @file buffered_serial.h + * @author Tyler Weaver + * + * @section LICENSE + * + * 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, + * including without limitation the rights to use, copy, modify, merge, publish, distribute, + * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all copies or + * substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING + * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * @section DESCRIPTION + * + * Buffered serial UART1 - Setup to work with UART1 (p13,p14) + * + * Uses RTOS to block current thread. + */ #ifndef BUFFERED_SERIAL_H #define BUFFERED_SERIAL_H @@ -8,20 +32,37 @@ #define BUFFER_SIZE 255 #define LINE_SIZE 80 #define NEXT(x) ((x+1)&BUFFER_SIZE) -#define IS_TX_FULL (((tx_in + 1) & BUFFER_SIZE) == tx_out) -#define IS_RX_FULL (((rx_in + 1) & BUFFER_SIZE) == rx_out) -#define IS_RX_EMPTY (rx_in == rx_out) +#define IS_TX_FULL (((tx_in_ + 1) & BUFFER_SIZE) == tx_out_) +#define IS_RX_FULL (((rx_in_ + 1) & BUFFER_SIZE) == rx_out_) +#define IS_RX_EMPTY (rx_in_ == rx_out_) #include "mbed.h" #include "rtos.h" - +/** Buffered serial UART1 - Setup to work with UART1 (p13,p14) + * + * Uses RTOS to block current thread. + */ class BufferedSerial : public Serial { public: - BufferedSerial(PinName tx, PinName rx); + /** Default Constructor + * Initialize UART1 - Serial(p13,p14) + * Initialize Semaphores + * Attach Serial Interrupts + */ + BufferedSerial(); - void send_line(char*); - void read_line(char*); + /** Put cstring in buffer/output + * + * @param cstring to put in buffer for printing (max length = 80 characters) + */ + void put_line(char*); + + /** Gets a cstring from the buffer/input + * + * @param buffer cstring to put line from buffer in (ends at '\n' or 80 characters) + */ + void get_line(char*); private: void Tx_interrupt(); @@ -32,23 +73,23 @@ // Circular buffers for serial TX and RX data - used by interrupt routines // might need to increase buffer size for high baud rates - char tx_buffer[BUFFER_SIZE]; - char rx_buffer[BUFFER_SIZE]; + char tx_buffer_[BUFFER_SIZE]; + char rx_buffer_[BUFFER_SIZE]; // Circular buffer pointers // volatile makes read-modify-write atomic - volatile int tx_in; - volatile int tx_out; - volatile int rx_in; - volatile int rx_out; + volatile int tx_in_; + volatile int tx_out_; + volatile int rx_in_; + volatile int rx_out_; // Line buffers for sprintf and sscanf - char tx_line[LINE_SIZE]; - char rx_line[LINE_SIZE]; + char tx_line_[LINE_SIZE]; + char rx_line_[LINE_SIZE]; //DigitalOut led1; // debug //DigitalOut led2; - Semaphore rx_sem; - Semaphore tx_sem; + Semaphore rx_sem_; + Semaphore tx_sem_; }; #endif \ No newline at end of file