Make examples friendlier for non GCC compilers and fixed slave_mem_i2c.c to compile on boards without I2C pins (#336)

i2c/bmp280_i2c/bmp280_i2c.c

@@ -214,6 +214,7 @@ int main() {
 #if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
     #warning i2c / bmp280_i2c example requires a board with I2C pins
         puts("Default I2C pins were not defined");
+    return 0;
 #else
     // useful information for picotool
     bi_decl(bi_2pins_with_func(PICO_DEFAULT_I2C_SDA_PIN, PICO_DEFAULT_I2C_SCL_PIN, GPIO_FUNC_I2C));
@@ -248,7 +249,5 @@ int main() {
         // poll every 500ms
         sleep_ms(500);
     }
-
 #endif
-    return 0;
 }

i2c/ht16k33_i2c/ht16k33_i2c.c

@@ -224,7 +224,5 @@ again:
     ht16k33_set_blink(0);
 
     goto again;
-
-    return 0;
 #endif
 }

i2c/lcd_1602_i2c/lcd_1602_i2c.c

@@ -163,7 +163,5 @@ int main() {
             lcd_clear();
         }
     }
-
-    return 0;
 #endif
 }

i2c/lis3dh_i2c/lis3dh_i2c.c

@@ -122,8 +122,7 @@ int main() {
         sleep_ms(500);
 
         // Clear terminal 
-        printf("\e[1;1H\e[2J");
+        printf("\033[1;1H\033[2J");
     }
 #endif
-    return 0;
 }

i2c/mma8451_i2c/mma8451_i2c.c

@@ -121,7 +121,7 @@ int main() {
         sleep_ms(500);
 
         // Clear terminal 
-        printf("\e[1;1H\e[2J");
+        printf("\033[1;1H\033[2J");
     }
 
 #endif

i2c/mpl3115a2_i2c/mpl3115a2_i2c.c

@@ -148,12 +148,15 @@ void mpl3115a2_convert_fifo_batch(uint8_t start, volatile uint8_t buf[], struct
 
     // 3 altitude registers: MSB (8 bits), CSB (8 bits) and LSB (4 bits, starting from MSB)
     // first two are integer bits (2's complement) and LSB is fractional bits -> makes 20 bit signed integer
-    int32_t h = (int32_t) ((uint32_t) buf[start] << 24 | buf[start + 1] << 16 | buf[start + 2] << 8);
+    int32_t h = (int32_t) buf[start] << 24;
+    h |= (int32_t) buf[start + 1] << 16;
+    h |= (int32_t) buf[start + 2] << 8;
     data->altitude = ((float)h) / 65536.f;
 
     // 2 temperature registers: MSB (8 bits) and LSB (4 bits, starting from MSB)
     // first 8 are integer bits with sign and LSB is fractional bits -> 12 bit signed integer
-    int16_t t = (int16_t) (((uint16_t) buf[start + 3]) << 8 | buf[start + 4]);
+    int16_t t = (int16_t) buf[start + 3] << 8;
+    t |= (int16_t) buf[start + 4];
     data->temperature = ((float)t) / 256.f;
 }
 
@@ -162,6 +165,7 @@ int main() {
 #if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
 #warning i2c / mpl3115a2_i2c example requires a board with I2C pins
     puts("Default I2C pins were not defined");
+    return 0;
 #else
     printf("Hello, MPL3115A2. Waiting for something to interrupt me!...\n");
 
@@ -202,5 +206,4 @@ int main() {
     };
 
 #endif
-    return 0;
 }

i2c/mpu6050_i2c/mpu6050_i2c.c

@@ -82,6 +82,7 @@ int main() {
 #if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
     #warning i2c/mpu6050_i2c example requires a board with I2C pins
     puts("Default I2C pins were not defined");
+    return 0;
 #else
     printf("Hello, MPU6050! Reading raw data from registers...\n");
 
@@ -111,7 +112,5 @@ int main() {
 
         sleep_ms(100);
     }
-
 #endif
-    return 0;
 }

i2c/pa1010d_i2c/pa1010d_i2c.c

@@ -24,7 +24,7 @@
 */
 
 const int addr = 0x10;
-const int max_read = 250;
+#define MAX_READ 250
 
 #ifdef i2c_default
 
@@ -44,24 +44,24 @@ void pa1010d_parse_string(char output[], char protocol[]) {
     int p = com_index - output;
 
     // Splits components of output sentence into array
-    int no_of_fields = 14;
-    int max_len = 15;
+#define NO_OF_FIELDS 14
+#define MAX_LEN 15
 
     int n = 0;
     int m = 0;
 
-    char gps_data[no_of_fields][max_len];
+    char gps_data[NO_OF_FIELDS][MAX_LEN];
     memset(gps_data, 0, sizeof(gps_data));
 
     bool complete = false;
-    while (output[p] != '$' && n < max_len && complete == false) {
+    while (output[p] != '$' && n < MAX_LEN && complete == false) {
         if (output[p] == ',' || output[p] == '*') {
             n += 1;
             m = 0;
         } else {
             gps_data[n][m] = output[p];
             // Checks if sentence is complete
-            if (m < no_of_fields) {
+            if (m < NO_OF_FIELDS) {
                 m++;
             } else {
                 complete = true;
@@ -92,15 +92,15 @@ void pa1010d_parse_string(char output[], char protocol[]) {
 }
 
 void pa1010d_read_raw(char numcommand[]) {
-    uint8_t buffer[max_read];
+    uint8_t buffer[MAX_READ];
 
     int i = 0;
     bool complete = false;
 
-    i2c_read_blocking(i2c_default, addr, buffer, max_read, false);
+    i2c_read_blocking(i2c_default, addr, buffer, MAX_READ, false);
 
     // Convert bytes to characters
-    while (i < max_read && complete == false) {
+    while (i < MAX_READ && complete == false) {
         numcommand[i] = buffer[i];
         // Stop converting at end of message 
         if (buffer[i] == 10 && buffer[i + 1] == 10) {
@@ -119,7 +119,7 @@ int main() {
     puts("Default I2C pins were not defined");
 #else
 
-    char numcommand[max_read];
+    char numcommand[MAX_READ];
 
     // Decide which protocols you would like to retrieve data from
     char init_command[] = "$PMTK314,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0*29\r\n";
@@ -140,7 +140,7 @@ int main() {
 
     while (1) {
         // Clear array
-        memset(numcommand, 0, max_read);
+        memset(numcommand, 0, MAX_READ);
         // Read and re-format
         pa1010d_read_raw(numcommand);
         pa1010d_parse_string(numcommand, "GNRMC");
@@ -149,8 +149,7 @@ int main() {
         sleep_ms(1000);
 
         // Clear terminal 
-        printf("\e[1;1H\e[2J");
+        printf("\033[1;1H\033[2J");
     }
 #endif
-    return 0;
 }

i2c/pcf8523_i2c/pcf8523_i2c.c

@@ -156,9 +156,8 @@ int main() {
         sleep_ms(500);
 
         // Clear terminal 
-        printf("\e[1;1H\e[2J");
+        printf("\033[1;1H\033[2J");
     }
 #endif
-    return 0;
 }
 

i2c/slave_mem_i2c/slave_mem_i2c.c

@@ -14,6 +14,7 @@
 static const uint I2C_SLAVE_ADDRESS = 0x17;
 static const uint I2C_BAUDRATE = 100000; // 100 kHz
 
+#ifdef i2c_default
 // For this example, we run both the master and slave from the same board.
 // You'll need to wire pin GP4 to GP6 (SDA), and pin GP5 to GP7 (SCL).
 static const uint I2C_SLAVE_SDA_PIN = PICO_DEFAULT_I2C_SDA_PIN; // 4
@@ -124,11 +125,18 @@ static void run_master() {
         sleep_ms(2000);
     }
 }
+#endif
 
 int main() {
     stdio_init_all();
+#if !defined(i2c_default) || !defined(PICO_DEFAULT_I2C_SDA_PIN) || !defined(PICO_DEFAULT_I2C_SCL_PIN)
+#warning i2c / slave_mem_i2c example requires a board with I2C pins
+    puts("Default I2C pins were not defined");
+    return 0;
+#else
     puts("\nI2C slave example");
 
     setup_slave();
     run_master();
+#endif
 }