Remove <SoftwareSPI.h> and use DELAY_NS

MarlinFirmware · Sep 3, 2021 · 9854cf4 · 9854cf4
1 parent 1c4894d
commit 9854cf4
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Showing 2 changed files with 27 additions and 32 deletions.
diff --git a/Marlin/src/libs/MAX31865.cpp b/Marlin/src/libs/MAX31865.cpp
@@ -51,10 +51,6 @@
 //#include <SoftwareSPI.h> // TODO: switch to SPIclass/SoftSPI
 #include "MAX31865.h"
 
-#ifdef TARGET_LPC1768
-  #include <SoftwareSPI.h>
-#endif
-
 // The maximum speed the MAX31865 can do is 5 MHz
 SPISettings MAX31865::spiConfig = SPISettings(
   TERN(TARGET_LPC1768, SPI_QUARTER_SPEED, TERN(ARDUINO_ARCH_STM32, SPI_CLOCK_DIV4, 500000)),
@@ -146,7 +142,7 @@ void MAX31865::begin(max31865_numwires_t wires, float zero, float ref) {
   OUT_WRITE(_cs, HIGH);
 
   if (_sclk != TERN(LARGE_PINMAP, -1UL, -1)) {
-    softSpiBegin(); // Define pin modes for Software SPI
+    softSpiBegin(SPI_QUARTER_SPEED); // Define pin modes for Software SPI
   }
   else {
     #ifdef MAX31865_DEBUG
@@ -461,34 +457,35 @@ uint8_t MAX31865::spixfer(uint8_t x) {
   return softSpiTransfer(x);
 }
 
-void MAX31865::softSpiBegin() {
+void MAX31865::softSpiBegin(uint8_t spi_speed) {
   #ifdef MAX31865_DEBUG
     SERIAL_ECHOLNPGM("Initializing MAX31865 Software SPI");
   #endif
-  #ifdef TARGET_LPC1768
-    swSpiBegin(_sclk, _miso, _mosi);
-    _spi_speed = swSpiInit(SPI_QUARTER_SPEED, _sclk, _mosi);
-  #else
-    OUT_WRITE(_sclk, LOW);
-    SET_OUTPUT(_mosi);
-    SET_INPUT(_miso);
-  #endif
+
+  // Calculate the actual clock speed
+  uint8_t target_clock_speed = 10000000/(2^spi_speed);
+
+  // Calculate delay in ns
+  _spi_speed = 1000000000/target_clock_speed;
+
+  OUT_WRITE(_sclk, LOW);
+  SET_OUTPUT(_mosi);
+  SET_INPUT(_miso);
 }
 
-uint8_t MAX31865::softSpiTransfer(uint8_t x) {
-  #ifdef TARGET_LPC1768
-    return swSpiTransfer(x, _spi_speed, _sclk, _miso, _mosi);
-  #else
-    uint8_t reply = 0;
-    for (int i = 7; i >= 0; i--) {
-      reply <<= 1;
-      WRITE(_sclk, HIGH);           // TODO: Delay?
-      WRITE(_mosi, x & (1 << i));   // TODO: Delay?
-      WRITE(_sclk, LOW);            // TODO: Delay?
-      if (READ(_miso)) reply |= 1;
-    }
-    return reply;
-  #endif
+uint8_t MAX31865::softSpiTransfer(uint8_t x) {  
+  uint8_t reply = 0;
+  for (int i = 7; i >= 0; i--) {    
+    WRITE(_mosi, x & (1 << i));
+    DELAY_NS(_spi_speed);
+    WRITE(_sclk, HIGH);
+    DELAY_NS(_spi_speed);
+    reply <<= 1;
+    if (READ(_miso)) reply |= 1;
+    WRITE(_sclk, LOW);
+    DELAY_NS(_spi_speed);
+  }
+  return reply;  
 }
 
 #endif // HAS_MAX31865 && !USE_ADAFRUIT_MAX31865
diff --git a/Marlin/src/libs/MAX31865.h b/Marlin/src/libs/MAX31865.h
@@ -90,9 +90,7 @@ class MAX31865 {
   static SPISettings spiConfig;
 
   TERN(LARGE_PINMAP, uint32_t, uint8_t) _sclk, _miso, _mosi, _cs;
-  #ifdef TARGET_LPC1768
-    uint8_t _spi_speed;
-  #endif
+  uint8_t _spi_speed;
   float Rzero, Rref;
 
   void setConfig(uint8_t config, bool enable);
@@ -104,7 +102,7 @@ class MAX31865 {
   void writeRegister8(uint8_t addr, uint8_t reg);
   uint8_t spixfer(uint8_t addr);
 
-  void softSpiBegin();
+  void softSpiBegin(uint8_t spi_speed);
 
   uint8_t softSpiTransfer(uint8_t x);