Preston Ernst
/
mirror_actuator_VT
-data logging revision
Diff: sw_fifo.cpp
- Revision:
- 2:92c25cb669f4
- Parent:
- 1:25a2b47ca291
diff -r 25a2b47ca291 -r 92c25cb669f4 sw_fifo.cpp --- a/sw_fifo.cpp Thu Aug 05 08:27:51 2021 +0000 +++ /dev/null Thu Jan 01 00:00:00 1970 +0000 @@ -1,285 +0,0 @@ -//////////////////////////////////////////////////////////////////////////////////////// -/* enter necessary header files for proper interrupt vector and UART/USART visibility */ -//////////////////////////////////////////////////////////////////////////////////////// - -#include <sw_fifo.h> -#include "uart_comm_thread.h" - -typedef struct { - uint8_t data_buf[FIFO_BUFFER_SIZE]; // FIFO buffer - uint16_t i_first; // index of oldest data byte in buffer - uint16_t i_last; // index of newest data byte in buffer - uint16_t num_bytes; // number of bytes currently in buffer -}sw_fifo_typedef; - -sw_fifo_typedef rx_fifo = { {0}, 0, 0, 0 }; // declare a receive software buffer -sw_fifo_typedef tx_fifo = { {0}, 0, 0, 0 }; // declare a transmit software buffer - - -/***************************************************************************************************************/ -// UART receive interrupt sub-routine -// - interrupts when valid data exists in rx hardware buffer -// - checks if there's room in the rx software buffer -// - if there's room, it transfers the received data into the sw buffer -// - automatically handles "uart_rx_buffer_full_flag" -// - sets overflow flag upon software buffer overflow (doesn't overwrite existing data) -////////////////////////////////////////////// -/* enter name of UART RX IRQ Handler here */ { -////////////////////////////////////////////// - - /* Explicitly clear the source of interrupt if necessary */ - - if(rx_fifo.num_bytes == FIFO_BUFFER_SIZE) { // if the sw buffer is full - uart_rx_fifo_ovf_flag = 1; // set the overflow flag - }else if(rx_fifo.num_bytes < FIFO_BUFFER_SIZE) { // if there's room in the sw buffer - - /////////////////////////////////////////////////// - /* read error/status reg here if desired */ - /* handle any hardware RX errors here if desired */ - /////////////////////////////////////////////////// - - ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// - rx_fifo.data_buf[rx_fifo.i_last] = /* enter pointer to UART rx hardware buffer here */ // store the received data as the newest data element in the sw buffer - ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// - - rx_fifo.i_last++; // increment the index of the most recently added element - rx_fifo.num_bytes++; // increment the bytes counter - } - if(rx_fifo.num_bytes == FIFO_BUFFER_SIZE) { // if sw buffer just filled up - uart_rx_fifo_full_flag = 1; // set the RX FIFO full flag - } - if(rx_fifo.i_last == FIFO_BUFFER_SIZE) { // if the index has reached the end of the buffer, - rx_fifo.i_last = 0; // roll over the index counter - } - uart_rx_fifo_not_empty_flag = 1; // set received-data flag -} // end UART RX IRQ handler -/***************************************************************************************************************/ - - -/***************************************************************************************************************/ -// UART transmit interrupt sub-routine -// - interrupts when the tx hardware buffer is empty -// - checks if data exists in the tx software buffer -// - if data exists, it places the oldest element of the sw buffer into the tx hardware buffer -// - if the sw buffer is emptied, it disables the "hw buffer empty" interrupt -// - automatically handles "uart_tx_buffer_full_flag" -////////////////////////////////////////////// -/* enter name of UART TX IRQ Handler here */ { -////////////////////////////////////////////// - - /* Explicitly clear the source of interrupt if necessary */ - - if(tx_fifo.num_bytes == FIFO_BUFFER_SIZE) { // if the sw buffer is full - uart_tx_fifo_full_flag = 0; // clear the buffer full flag because we are about to make room - } - if(tx_fifo.num_bytes > 0) { // if data exists in the sw buffer - - /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// - /* enter pointer to UART tx hardware buffer here */ = tx_fifo.data_buf[tx_fifo.i_first]; // place oldest data element in the TX hardware buffer - /////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// - - tx_fifo.i_first++; // increment the index of the oldest element - tx_fifo.num_bytes--; // decrement the bytes counter - } - if(tx_fifo.i_first == FIFO_BUFFER_SIZE) { // if the index has reached the end of the buffer, - tx_fifo.i_first = 0; // roll over the index counter - } - if(tx_fifo.num_bytes == 0) { // if no more data exists - - uart_tx_fifo_not_empty_flag = 0; // clear flag - - ////////////////////////////////////////////////////////////////////////// - /* disable UART "TX hw buffer empty" interrupt here */ - /* if using shared RX/TX hardware buffer, enable RX data interrupt here */ - ////////////////////////////////////////////////////////////////////////// - - } -}// end UART TX IRQ handler -/***************************************************************************************************************/ - - -/***************************************************************************************************************/ -// UART data transmit function -// - checks if there's room in the transmit sw buffer -// - if there's room, it transfers data byte to sw buffer -// - automatically handles "uart_tx_buffer_full_flag" -// - sets the overflow flag upon software buffer overflow (doesn't overwrite existing data) -// - if this is the first data byte in the buffer, it enables the "hw buffer empty" interrupt -void uart_send_byte(uint8_t byte) { - - /////////////////////////////////////////////////////////// - /* disable interrupts while manipulating buffer pointers */ - /////////////////////////////////////////////////////////// - - if(tx_fifo.num_bytes == FIFO_BUFFER_SIZE) { // no room in the sw buffer - uart_tx_fifo_ovf_flag = 1; // set the overflow flag - }else if(tx_fifo.num_bytes < FIFO_BUFFER_SIZE) { // if there's room in the sw buffer - tx_fifo.data_buf[tx_fifo.i_last] = byte; // transfer data byte to sw buffer - tx_fifo.i_last++; // increment the index of the most recently added element - tx_fifo.num_bytes++; // increment the bytes counter - } - if(tx_fifo.num_bytes == FIFO_BUFFER_SIZE) { // if sw buffer is full - uart_tx_fifo_full_flag = 1; // set the TX FIFO full flag - } - if(tx_fifo.i_last == FIFO_BUFFER_SIZE) { // if the "new data" index has reached the end of the buffer, - tx_fifo.i_last = 0; // roll over the index counter - } - - /////////////////////// - /* enable interrupts */ - /////////////////////// - - if(tx_fifo.num_bytes > 0) { // if there is data in the buffer - - uart_tx_fifo_not_empty_flag = 1; // set flag - - /////////////////////////////////////////////////////////////////////////// - /* if using shared RX/TX hardware buffer, disable RX data interrupt here */ - /* enable UART "TX hw buffer empty" interrupt here */ - /////////////////////////////////////////////////////////////////////////// - - } -} -/***************************************************************************************************************/ - - -/***************************************************************************************************************/ -// UART data receive function -// - checks if data exists in the receive sw buffer -// - if data exists, it returns the oldest element contained in the buffer -// - automatically handles "uart_rx_buffer_full_flag" -// - if no data exists, it clears the uart_rx_flag -uint8_t uart_get_byte(void) { - - /////////////////////////////////////////////////////////// - /* disable interrupts while manipulating buffer pointers */ - /////////////////////////////////////////////////////////// - - uint8_t byte = 0; - if(rx_fifo.num_bytes == FIFO_BUFFER_SIZE) { // if the sw buffer is full - uart_rx_fifo_full_flag = 0; // clear the buffer full flag because we are about to make room - } - if(rx_fifo.num_bytes > 0) { // if data exists in the sw buffer - byte = rx_fifo.data_buf[rx_fifo.i_first]; // grab the oldest element in the buffer - rx_fifo.i_first++; // increment the index of the oldest element - rx_fifo.num_bytes--; // decrement the bytes counter - }else{ // RX sw buffer is empty - uart_rx_fifo_not_empty_flag = 0; // clear the rx flag - } - if(rx_fifo.i_first == FIFO_BUFFER_SIZE) { // if the index has reached the end of the buffer, - rx_fifo.i_first = 0; // roll over the index counter - } - - /////////////////////// - /* enable interrupts */ - /////////////////////// - - return byte; // return the data byte -} -/***************************************************************************************************************/ -sw_fifo.h -sw_fifo.h (1.5 KB) -#define FIFO_BUFFER_SIZE 128 // software buffer size (in bytes) - -// UART data transmit function -// - checks if there's room in the transmit sw buffer -// - if there's room, it transfers data byte to sw buffer -// - automatically handles "uart_tx_buffer_full_flag" -// - sets the overflow flag upon software buffer overflow (doesn't overwrite existing data) -// - if this is the first data byte in the buffer, it enables the "hw buffer empty" interrupt -void uart_send_byte(uint8_t byte); - - -// UART data receive function -// - checks if data exists in the receive sw buffer -// - if data exists, it returns the oldest element contained in the buffer -// - automatically handles "uart_rx_buffer_full_flag" -// - if no data exists, it clears the uart_rx_flag -uint8_t uart_get_byte(void); - -volatile extern uint8_t uart_rx_fifo_not_empty_flag; // this flag is automatically set and cleared by the software buffer -volatile extern uint8_t uart_rx_fifo_full_flag; // this flag is automatically set and cleared by the software buffer -volatile extern uint8_t uart_rx_fifo_ovf_flag; // this flag is not automatically cleared by the software buffer -volatile extern uint8_t uart_tx_fifo_full_flag; // this flag is automatically set and cleared by the software buffer -volatile extern uint8_t uart_tx_fifo_ovf_flag; // this flag is not automatically cleared by the software buffer -volatile extern uint8_t uart_tx_fifo_not_empty_flag; // this flag is automatically set and cleared by the software buffer - -// What I should post into the main: -///////////////////////////////////////////////////////////////////////// -///////////////////////////////////////////////////////////////////////// - -/* -#include <sw_fifo.h> // make software buffer visible to this file - -volatile uint8_t uart_rx_fifo_not_empty_flag = 0; -volatile uint8_t uart_rx_fifo_full_flag = 0; -volatile uint8_t uart_rx_fifo_ovf_flag = 0; -volatile uint8_t uart_tx_fifo_full_flag = 0; -volatile uint8_t uart_tx_fifo_ovf_flag = 0; -volatile uint8_t uart_tx_fifo_not_empty_flag = 0; - -int main (void) { - uint8_t i = 0; - uint8_t rx_data = 0; - - // initialize clocks - // disable global interrupts - // initialize gpio - // initialize uart/usart - - // enable "UART RX" interrupt and "TX hardware buffer empty" interrupt - // enable global interrupts - - while(uart_tx_fifo_full_flag); // wait for room to open up in the software buffer - uart_send_byte('A'); // transmit ASCII character 'A' - while(uart_tx_fifo_full_flag); - uart_send_byte(0x41); // transmit ASCII character 'A' - - // transmit ASCII characters 1-5 - for(i=0; i<5; i++) { - while(uart_tx_fifo_full_flag); - uart_send_byte(i+48); - } - - while(1) { - // enter sleep mode if supported (wake from UART Rx) - - while(uart_rx_fifo_not_empty_flag) { // if data exists in software buffer - rx_data = uart_get_byte(); // grab first data byte from software buffer - - /* handle received byte as desired */ - - - uart_send_byte(rx_data); // example of how to echo received ASCII characters - } - - // check for rx overflow condition - if(uart_rx_fifo_ovf_flag) { - - /* handle rx overflow condition as desired */ - - uart_rx_fifo_ovf_flag = 0; // clear the rx overflow flag - } - - // check for tx overflow condition - if(uart_tx_fifo_ovf_flag) { - - /* handle tx overflow condition as desired */ - - uart_tx_fifo_ovf_flag = 0; // clear the tx overflow flag - } - - // if you need to disable global interrupts, you should wait until the tx fifo is empty - while(uart_tx_fifo_not_empty_flag); - /* Disable global interrupts */ - - /* Do something */ - - /* Re-enable global interrupts */ - } // end while -} // end main -*/ - - - -