theoretically done display fw

final_project/.gitignore

@@ -0,0 +1,4 @@
+*.map
+*.o
+*.out
+*-bak

final_project/comms/comms.h

@@ -13,7 +13,9 @@
 
 typedef enum {
     COMMS_CMD_CLR = 0U,         //! Clears LCD and all file names
-    COMMS_CMD_ADD_FILE,         //! Adds a file to the list of files to display, data is 1 byte for ID, 1 byte for strlen, n bytes for string
+    COMMS_CMD_NUM,              //! sends the total number of songs to choose from
+    COMMS_CMD_QUERY_NAME,       //! Queries for the name of a given song ID
+    COMMS_CMD_REPLY_NAME,       //! Responds with the name of the given song ID
     COMMS_CMD_SELECT_FILE,      //! selects a file from the given list to play, data is 1 byte for id
     COMMS_CMD_PLAY,             //! Starts playing file
     COMMS_CMD_PAUSE             //! pauses playing file
@@ -21,51 +23,44 @@ typedef enum {
 
 /** @brief Inline function to send commands and values.
  */
-inline void comms_send_command(comms_cmd_t cmd) {
+inline void comms_send(comms_cmd_t cmd) {
     while (! (UCSRA & (1 << UDRE)));
     UDR = cmd;
 }
 
-/** @brief Adds a file to the list on the LCD side.
- */
-inline void comms_add_file(uint8_t id, char* filename) {
-    uint8_t len = strlen(filename);
-
-    comms_send_command(COMMS_CMD_ADD_FILE);
-    comms_send_command((comms_cmd_t) id);
-
-    uint8_t i = 0;
-    while (i < len) {
-        comms_send_command((comms_cmd_t) filename[i]);
-    }
-}
-
 /** @brief Selects a file from the list on the DAC side.
  * 
  * If another song is playing, this will stop
  * that song from playing and select the new one.
  */
 inline void comms_select_file(uint8_t id) {
-    comms_send_command(COMMS_CMD_SELECT_FILE);
-    comms_send_command((comms_cmd_t) id);
+    comms_send(COMMS_CMD_SELECT_FILE);
+    comms_send((comms_cmd_t) id);
+}
+
+/** @brief Queries for the name of the given song ID.
+ */
+inline void comms_query_name(uint8_t id) {
+    comms_send(COMMS_CMD_QUERY_NAME);
+    comms_send(id);
 }
 
 /** @brief Clears the LCD list of files.
  */
 inline void comms_clear() {
-    comms_send_command(COMMS_CMD_CLR);
+    comms_send(COMMS_CMD_CLR);
 }
 
 /** @brief Starts playing song.
  */
 inline void comms_play() {
-    comms_send_command(COMMS_CMD_PLAY);
+    comms_send(COMMS_CMD_PLAY);
 }
 
 /** @brief Pauses playing song.
  */
 inline void comms_pause() {
-    comms_send_command(COMMS_CMD_PLAY);
+    comms_send(COMMS_CMD_PLAY);
 }
 
 #endif

final_project/lcd_disp/fifo.h

@@ -9,7 +9,7 @@ typedef enum {
     FIFO_EMPTY
 } fifo_err_t;
 
-#define FIFO_LEN 50
+#define FIFO_LEN 20
 #define FIFO_TYPE uint8_t
 
 /** @brief Initialises FIFO

final_project/lcd_disp/main.c

@@ -1,52 +1,20 @@
 #include "main.h"
 
 /* ---- Global Flags ---- */
-int16_t display_song = -1;      //! ID of the song currently being displayed, -1 if song list is not initialised
-int16_t selected_song = -1;     //! ID of the selected song. -1 if no song is selected.
-bool update_display = false;    //! flag on whether or not to update display
+int8_t display_song = -1;          //! ID of the song currently being displayed, -1 if song list is not initialised
+int8_t last_displayed_song = -1;
+int8_t selected_song = -1;         //! ID of the selected song. -1 if no song is selected.
+bool update_display = false;        //! flag on whether or not to update display
 
 struct {
-    char* names[MAX_SONGS];     //! array of all song names, names are allocated on heap
-    uint8_t num_songs;      //! Number of songs loaded into display memory
-    bool playing;       //! Whether the currently selected song is playing
+    char name[SONG_NAME_LEN + 1];   //! array of all song names, names are allocated on heap
+    uint8_t num_songs;              //! Number of songs loaded into display memory
+    bool playing;                   //! Whether the currently selected song is playing
 } songs;
 
-/** @brief Adds song to list of songs
- * 
- * Allocates a new piece of memory for the name.
+
+/** @brief Handles right button press
  */
-/*
-void add_song(char* name) {
-    // Error out on too many songs
-    if (songs.num_songs == MAX_SONGS) {
-        lcd_gotoxy(0,0);
-        lcd_puts("Too many songs!");
-        while(1);
-    }
-
-    // Allocate memory to store name, and increase number
-    uint8_t name_len = strlen(name);
-    songs.names[songs.num_songs] = malloc(name_len);
-    songs.num_songs++;
-}
-*/
-
-/** @brief Clears list of songs
- * 
- * Frees all memory used for name storage
- */
-/*
-void clear_songs() {
-    // Free all memory
-    for (uint8_t i = 0; i < songs.num_songs; i++) {
-        free(songs.names[i]);
-    }
-
-    songs.num_songs = 0;
-}
-*/
-
-
 void handle_left_press() {
     if (songs.num_songs == 0) {
         lcd_clrscr();
@@ -60,6 +28,8 @@ void handle_left_press() {
     }
 }
 
+/** @brief Handles left button press
+ */
 void handle_right_press() {
     if (songs.num_songs == 0) {
         lcd_clrscr();
@@ -120,6 +90,21 @@ int main() {
     while (1) {
         // Handle incoming messages
         if (fifo_pop(&incoming_cmd) == FIFO_SUCCESS) {
+            switch (incoming_cmd) {
+                // Clear songs, so there are none to display
+                case (COMMS_CMD_CLR):
+                    songs.num_songs = 0;
+                    display_song = -1;
+                    break;
+                // change number of songs
+                case (COMMS_CMD_NUM):
+                    while(fifo_pop((FIFO_TYPE*) &songs.num_songs) != FIFO_SUCCESS);
+                    break;
+                default:
+                    lcd_clrscr();
+                    lcd_puts("Incorrect command!");
+                    break;
+            }
             
         }
 
@@ -143,16 +128,44 @@ int main() {
 
         // Update display periodically
         if (update_display) {
+            // check if song has changed
+            if (last_displayed_song != display_song) {
+                comms_query_name(display_song);
+
+                char tmp_chr;
+
+                // Wait for command to come in
+                while (fifo_pop((FIFO_TYPE*) &tmp_chr) != FIFO_SUCCESS);
+
+                // TODO add error handling here
+
+                // Wait for length info to come in
+                while (fifo_pop((FIFO_TYPE*) &tmp_chr) != FIFO_SUCCESS);
+                uint8_t len = tmp_chr;
+
+                // Read in string
+                for (uint8_t i = 0; i < len; i++) {
+                    // Hold until fifo returns successfully
+                    while(fifo_pop((FIFO_TYPE*) &songs.name[i]) != FIFO_SUCCESS);
+                }
+            }
             lcd_clrscr();
-            lcd_gotoxy(0,0);
-            lcd_puts(songs.names[display_song]);
-            lcd_gotoxy(0, 1);
-            //char tmp_string[17];
-            //sprintf(tmp_string, "%1d         %2d/%2d",
-            //        display_song, display_song, songs.num_songs);
-            //lcd_puts(tmp_string);
+
+            if (display_song != -1) {
+                lcd_puts(songs.name);
+                lcd_gotoxy(0, 1);
+                lcd_putc('1' + display_song);
+                lcd_gotoxy(13,1);
+                lcd_putc('1' + display_song);
+                lcd_putc('/');
+                lcd_putc('0' + songs.num_songs);
+
+            } else {
+                lcd_puts("No song!");
+            }
 
             update_display = false;
+            last_displayed_song = display_song;
         }
     }
 

final_project/lcd_disp/main.h

@@ -15,7 +15,7 @@
 #include "comms.h"
 #include "periph.h"
 
-#define MAX_SONGS 16
+#define SONG_NAME_LEN 16
 
 /* ---- Globally available flags ---- */
 extern bool update_display;