Differences

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--- arduino:gammon-spi-controller [2023/07/24 16:17] – created mithat
+++ arduino:gammon-spi-controller [2023/07/24 18:43] (current) – mithat
@@ Line 1: / Line 1: @@
-From [[http://www.gammon.com.au/spi|SPI - Serial Peripheral Interface - for Arduino]] by Nick Gammon.
+From [[http://www.gammon.com.au/spi|SPI - Serial Peripheral Interface - for Arduino]] by Nick Gammon. Modified to use the newish and preferred ''SPI.beginTransaction()'' and ''SPI.endTransaction()''.
-<file cpp spi-controller.ino>
+<file cpp gammon-spi-controller.ino>
 // Written by Nick Gammon
 // February 2011
+// With Mithat Mods -- July 2023
 #include <SPI.h>
@@ Line 19: / Line 19: @@
   // Slow down the master a bit
-  SPI.setClockDivider(SPI_CLOCK_DIV8);
+//  SPI.setClockDivider(SPI_CLOCK_DIV8);  // mithat: let's do this the preferred way
 }  // end of setup
@@ Line 28: / Line 28: @@
   char c;
+  SPI.beginTransaction(SPISettings(400000, MSBFIRST, SPI_MODE0));  // mithat: this is the preferred way
   // enable Slave Select
@@ Line 33: / Line 35: @@
   // send test string
-  for (const char * p = "Hello, world!\n" ; c = *p; p++)
+  for (const char * p = "Hello, world!\n" ; (c = *p); p++)
+  {
     SPI.transfer (c);
+    delayMicroseconds(5);    // mithat: added small delay to make things work at given speed
+  }
   // disable Slave Select
   digitalWrite(SS, HIGH);
+  SPI.endTransaction();      // mithat: finish preferred way
   delay (1000);  // 1 seconds delay
 }  // end of loop
 </file>