fix(spi): update examples after SPI rework

Signed-off-by: Frederic Pillon <frederic.pillon@st.com>

Author: fpistm

examples/NonReg/SPI_loop/SPI_loop.ino

@@ -24,34 +24,46 @@
 #warning "LED_BUILTIN is not defined."
 #endif
 
-#define MOSI_PIN  PIN_SPI_MOSI
-#define MISO_PIN  PIN_SPI_MISO
-#define SCK_PIN   PIN_SPI_SCK
-#define CS_PIN    PIN_SPI_SS
+/* Set to 1 if CS have to be managed by the hardware */
+#define CS_HARDWARE_CONTROL 0
+
+#define MOSI_PIN PIN_SPI_MOSI
+#define MISO_PIN PIN_SPI_MISO
+#define SCK_PIN PIN_SPI_SCK
+#define CS_PIN PIN_SPI_SS
 
 uint8_t buffer_tx[] = "Thequickbrownfoxjumpsoverthelazydog\0";
-#define BUF_SIZE  sizeof(buffer_tx)
+#define BUF_SIZE sizeof(buffer_tx)
 uint8_t buffer_rx[BUF_SIZE] = {};
 
 /* SPI transfer loop nb */
 #define TEST_LOOP_NB 9
 
 void setup() {
-  uint8_t tested_ok = 0; // test result
+  uint8_t tested_ok = 0;  // test result
 
   SPI.setMOSI(MOSI_PIN);
   SPI.setMISO(MISO_PIN);
   SPI.setSCLK(SCK_PIN);
-  // Don't set CS_PIN to have Software ChipSelect management
-  // Instead, CS_PIN is passed as argument to SPI.transfer(CS_PIN)
-  // SPI.setSSEL(CS_PIN);
+#if CS_HARDWARE_CONTROL == 1
+  SPI.setSSEL(CS_PIN);
+#endif
+#if CS_HARDWARE_CONTROL == 0
+  pinMode(CS_PIN, OUTPUT);
+  digitalWrite(CS_PIN, HIGH);
+#endif
 
   /* the SPI pin configuration is done by the SPI.begin */
-   SPI.begin(CS_PIN);
+  SPI.begin();
 
   for (uint8_t received = 0; received < TEST_LOOP_NB; received++) {
-    SPI.transfer(CS_PIN, buffer_tx, buffer_rx, BUF_SIZE, SPI_LAST);
-
+#if CS_HARDWARE_CONTROL == 0
+    digitalWrite(CS_PIN, LOW);
+#endif
+    SPI.transfer(buffer_tx, buffer_rx, BUF_SIZE);
+#if CS_HARDWARE_CONTROL == 0
+    digitalWrite(CS_PIN, HIGH);
+#endif
     /* compare what is received to what was sent */
     if (!memcmp(buffer_tx, buffer_rx, BUF_SIZE)) {
       /* this transfer passed */
@@ -60,14 +72,14 @@ void setup() {
     memset(buffer_rx, 0, BUF_SIZE);
   }
   /* display test result */
-  pinMode(LED_BUILTIN, OUTPUT);   // Configure LED pin, for test result
-  digitalWrite(LED_BUILTIN, LOW); // start with led off
+  pinMode(LED_BUILTIN, OUTPUT);    // Configure LED pin, for test result
+  digitalWrite(LED_BUILTIN, LOW);  // start with led off
   if (tested_ok == TEST_LOOP_NB) {
-      /* success */
-      digitalWrite(LED_BUILTIN, HIGH);
+    /* success */
+    digitalWrite(LED_BUILTIN, HIGH);
   } else {
-      /* error. Please verify MISO is externally connected to MOSI */
-      digitalWrite(LED_BUILTIN, LOW);
+    /* error. Please verify MISO is externally connected to MOSI */
+    digitalWrite(LED_BUILTIN, LOW);
   }
 }